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Unit -1 Crop Production & Management

1. Introduction
The science that deals with the growth of plants and animals for human use is
called agriculture.
Agriculture includes-

 Soil management- the cultivation of soil

 Crop farming- growing and harvesting of crops.
 Horticulture- growing and harvesting of fruits, vegetables, flowers and decorative
plants
 Animal husbandry- the breeding and raising of livestock including poultry
The land where plants are cultivated is known as fields.
Plants grown in large quantities in field are known as crop plants or crops.
Based upon the seasons, the crops are divided into two types- summer crops called kharif
crops and winter crops called rabi crops.
Kharif crops are grown during summer between june/july and harvested by september/october.
Rice, groundnut, maize, cotton , pulses are some common kharif crps.
Rabi crops are grown in the winter between october/november and harvestedv by march or
april. Wheat, barley, mustard, potato and peas are some common rabi crops.
The recent progress in agriculture has taught farmers to cultivate crops in a systematic way.
The tasks that a farmer follows are called agricultural practices. The major steps involved in
this process are-

 Preparation of soil
 Selection and sowing of seeds
 Addition of manure and fertilizers
 Irrigation
 Protection from weeds and pests
 Harvesting
 Storage
Preparation of soil:
Ploughing or tilling involves loosening and turning of soil using a tool or an implement called
the plough. Then the soil is leveled.
Loosening of the soil-
1. Allows the roots to breath easily
2. Helps the roots to penetrate deeper into the soil.
3. Enables fertilizers to mix uniformly with the soil.
4. Aids the growth of organisms such as earthworms, millipedes, bacteria and fungi.
Sowing of seeds:
Seeds used for sowing should be of good quality, healthy, viable and free of infections. Seeds
are sown manually by broadcasting or by seed drills. Broadcasting is the scattering of seeds
over the soil surface by hand.
Sowing
Scattering seeds on the Earth after soil is prepared for cultivation is termed as
Sowing. It is the most important part of agriculture. Plants can’t grow without

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seeds. The type of seeds sown decides the quality of crops that would come out of
it.

Good quality seeds should always be sown. Good quality seeds (clean healthy
seeds with high yielding capacity) can be easily distinguished from the bad ones.
Once put in water and the left for some time, the damaged seeds being light &
hollow would float on the surface.

Manual sowing of seeds involves time and labor. Equipment like seed drill helps in
sowing seeds using a tractor. Some advantages of using a Seed Drill are:

 Sow seeds at uniform distances

 Protect seeds from being eaten by birds
 Saves time
 Saves human labor
Addition of manure and fertilizers:
Plants require nutrients for growth. They get these nutrients from the soil. This can be done
either by natural methods or by adding manures and fertilizers to the soil.
Natural methods:
Field fallow: The method of leaving the field without cultivating any crops to replenish nutrients
in the soil.
Crop rotation: It involves growing two or more crops alternatively on the same land in the same
growing season so that the soil is not depleted of any particular nutrients.

Differences between manures and fertilizers:

Irrigation:
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Irrigation is the artificial supply of water to farms when needed.

Some of the modern irrigation methods are as follows:
 Sprinkler system
 Drip irrigation
 Modern methods of irrigation
 Modern methods of irrigation being able to overcome the limitations of
traditional methods are encouraged these days. Some of the modern
methods of irrigation are:
 Sprinkler system
 In this system, there are perpendicular pipes with rotating nozzles on top.
These pipes are joined to the main pipeline. Water flows through main
pipeline under pressure by a pump. Water escapes from the nozzles &
reaches the field.


Drip system
 In this system, water falls drop wise near roots. Therefore, there is no
wastage of water. This method is very good for areas with less water.


 Modern methods are more efficient with no water wastage and no human
labor involved.
Protection from weed and pests:
Weeding:
 Weeds are unwanted plants that grow along with the crops. They compete with the
crops for water, minerals and sunlight and, therefore reduce crop yield.
 Amaranthus is very common weed which grow with almost every crop.
 Weeding can be done manully using a trowel or a harrow or by using a seed drill
using certain chemicals called weedicides for example- 2,4-D. some common
weedicides are Dalapon, Siniazine and Picloram.
Pests:
 Insects that attack crops and damage them are called pests.
 Pests can be controlled by pesticides which are poisonous chemicals. Pesticides kill
pests as well as their eggs and larvae but do not affect the plants.
Harvesting:
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 Harvesting is the cutting and gathering of the mature crop from the fields.
 Threshing is the process of removal of the edible part of grain from the scaly, inedible
chaff that surrounds it.
 Combine harvester is a farm machine which does both harvesting as well as
threshing.
 Wind winnowing is a method of separating grain from chaff by throwing the mixture
into the air with a winnowing fan.
Agricultural tools for soil preparation
Plough, Hoe & Cultivator are three important tools which help in soil preparation.
Plough
Tool used for ploughing . It is made of iron/ wood. It is pulled by a pair of animals like cows/ oxen/
horses and operated by the farmer through the handle. It has 3 important parts:

 Ploughshare: strong triangular iron strip

 Plough shaft: long log of wood
 Beam: stand placed on animals’ neck

Hoe
Hoe is a tool used for loosening soil. It is made of wood or iron. A strong iron plate attached to the long
rod acts like a blade and helps to loosen the soil. It is also pulled by animals.

Cultivator

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Cultivator is a tool used for ploughing. Manual as well as tractor driven cultivators are used. Tractor
driven cultivators are fast, thus save time and also saves human labor.
Storage:Large scale storage of grains is done in granaries or silos to protect them from pests
like rodents, microbes or insects.
Increasing crop produce:
Crop produce can be increased by increasing the land under cultivation, by improvement in
the methods of agriculture, and by developing better varieties of crops by plant breeding.
Hybridization is a technique used for plant breeding in which new varieties with desired
characteristics of high yield and resistance to disease, are developed.
Nitrogen cycle:
Air contains about 78% nitrogen. Nitrogen is used by life forms for the formation of protein,
amino acids and nucleic acids.

The cyclic process of nitrogen being fixed, used by plants and animals and later returned to
the atmosphere is referred to as the nitrogen cycle.
Nitrogen cycle involves the following steps:

 Nitrogen fixation: fixing free nitrogen gas of the atmosphere into inorganic
compounds by organism such as Rhizobium.
 Nitrogen assimilation: converting inorganic nitrogen into usable organic compounds in
organisms.
 Ammonification: Conversion of organic nitrogen into ammonia.
 Nitrification: Ammonia is converted into nitrates in the soil with the help of bacteria.
 Denitrification: Conversion of nitrates into nitrogen gas by denitrifying bacteria.
Animal husbandry:
 The breeding, feeding and caring of domestic animals for food and other purposes is
called animal husbandry.
 Meat or egg yielding animals such as goat, poultry animals (e.g. chicken, duck and
trkey), fish, sheep.
 Milch or (milk yielding) animals such as cow, buffalo, goat and camel.
 Large scale rearing of fish for food is known as pisciculture.
 Large scale rearing of honeybee is known as apiculture.

नमस्ते अब मै आपको इस चैप्टर की फुल समरी Hinglish में देता हूँ , लेकिन
इंग्लिश में समझना सीखो| कुछ पूछना हो तो कोचिंग में आकर पूछो,लेकिन
Ratna मत

📘 Agriculture क्या है?

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Agriculture वह विज्ञान है जिसमें पौधे और जानवरों को मानव उपयोग के लिए उगाया जाता
है।
Agriculture में शामिल हैं:
 Soil Management – मिट्टी की तैयारी और देखभाल
 Crop Production – अनाज, दालें, फल, सब्ज़ियाँ उगाना
 Horticulture – फल, फूल, सजावटी पौधे उगाना
 Animal Husbandry – पालतू जानवरों की देखभाल व पालन

🧭 Crops – Types based on Season

🌦 Type Season Examples
धान, मक्का, कपास,
Kharif June–Oct (Rainy)
मूंगफली
गेहूं, सरसों, मटर, जौ,
Rabi Oct–Apr (Winter)
आलू
🟨 Zaid Crops – गर्मी में (March–June), जैसे खरबूजा, तरबूज, ककड़ी

⚙️7 Major Agricultural Practices

1. Preparation of Soil
o Ploughing → Loosening of soil (by Plough, Hoe, Cultivator)
o Benefits: Roots grow deep, aeration improves, microbes flourish
2. Sowing
o Good quality, viable, disease-free seeds
o Manual (broadcasting) or mechanical (seed drill)
✅ Float Test – खराब बीज पानी में तैरते हैं
3. Adding Nutrients (Manure & Fertilizers)
Manure Fertilizer
Natural, organic Chemical, synthetic
Improves soil structure Fast growth but may harm soil
4. 🔁 Crop Rotation और Field Fallow – मिट्टी की उर्वरता बनाए रखते हैं
5. Irrigation (सिंचाई के तरीके)
o Traditional: moat, chain pump
o Modern:
 Sprinkler – नोज़ल से पानी फैलता है
 Drip – पानी बूंद-बूंद जड़ों तक पहुंचता है (Water-saving!)
6. Weeding & Pest Control
o Weeds: Amaranthus, Parthenium – फसल का पोषण छीनते हैं
o Weedicides: 2,4-D, Dalapon
o Pests: कीट जो फसल खाते हैं → Use Pesticides (kill eggs & larvae)
7. Harvesting
o फसल काटना, अलग करना (Threshing), हवा में उड़ाकर छँटाई (Winnowing)
o Combine Harvester: काटना + अलग करना एक साथ
8. Storage
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o Grains stored in granaries, silos → Pest-free रखने के लिए

📈 Crop Yield बढ़ाने के तरीके
 ज्यादा उपज देने वाले बीज (Hybrid seeds)
 अच्छी मिट्टी, बेहतर तकनीक
 Pest & weed control
 Scientific methods
🧪 Nitrogen Cycle – 5 Steps (for MCQs)
1. Nitrogen Fixation – Rhizobium bacteria हवा से N₂ को पकड़ते हैं
2. Assimilation – पौधे nitrogen को absorb करते हैं
3. Ammonification – Dead organisms → Ammonia
4. Nitrification – Ammonia → Nitrates (by bacteria)
5. Denitrification – Nitrate → Nitrogen gas (फिर हवा में वापसी)
🐄 Animal Husbandry
 Milch Animals – Cow, Buffalo, Goat
 Meat/Egg Animals – Chicken, Duck, Fish, Goat
 Apiculture – मधुमक्खी पालन
 Pisciculture – मछली पालन
🔬 Modern breeding technique: Hybridization
📚 Extra Exam-Ready Tips:
 Combine harvester = Harvester + Thresher
 Broadcasting = बीज हाथ से बिखेरना
 Drip Irrigation is best for water-scarce areas
Crop rotation helps avoid nutrient depletion
कुछ न समझ आये तो पूछ लेना 9455857477

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 Unit – 2 Micro- Organism Friends & Foe

Introduction
Microbes are extremely small organisms that cannot be seen with naked eyes. They are also called
‘Micro-organisms’. Examples: Bacteria, Fungi etc.

Microbes are not always harmful to us, but also helpful many a times. In this lesson, we will learn about
both Friendly microbes as well as Harmful microbes.
Classification of Microbes
Microbes are classified broadly into four groups:

 Bacteria
o Bacteria are one of the oldest life forms
o They are unicellular i.e. they are made up of one cell
o They appear in a variety of shapes & sizes (Spherical, elongated, spiral etc.)

 They inhabit soil, water, radioactive waste & the deep portions of Earth's crust. In fact, they also
live in plant /animal bodies
 They live in colonies
 Some of them are autotrophic (prepare their own food), while others are heterotrophic (depend on
others for their food)

 Fungi
You would have seen fungi as a white layer on bread when you leave it outside at room temperature for
quite a few days. Fungi get favorable conditions & therefore they grow.
But, the same bread when kept inside a refrigerator remains fresh for a longer period of time.

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Fungi are multicellular e. they are made up of multiple cells

 They are Heterotrophic (Depend on others for their food)

 They live in colonies and prefer warm & moist places to grow
 They are immobile
 Some common examples of fungi are: Yeast, Mushroom, Molds

Protozoa

o They are mostly Unicellular i.e. made of one cell

o Some of them are autotrophic (prepare their own food), while others are heterotrophic
(depend on others for their food)
o They prefer moist & aquatic habitats
o They can live singly, unlike bacteria & fungi
o Some common examples of protozoa are: Amoeba, Paramecium, Trypanosoma

 Algae
o They are multicellular i.e. Made of multiple cells
o They prefer mostly aquatic habitats
o Some common examples of protozoa are: Spirogyra, Ulothrix, Chlamydomonas

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Viruses: An exception
Viruses are also microscopic, but they are not considered as micro-organism. They behave like non-
living when outside host cell, and reproduce only when inside the host cell

Role of microbes in our life

You might know microbes only for causing harm to human beings by causing diseases and making us
ill.

But, the truth is microbes are also beneficial to us in a variety of ways. They help in preparation of
several household & industrial products like curd, cake, bread, antibiotics & beverages. They also help
the environment acting as decomposers and biofertilizers. They play an important in sewage treatment
as well.
Microbes’ role in Curdling of milk
Microbes play a vital role in preparing curd from milk. Curd contains a bacterium, Lactobacillus
Lactobacillus is a friendly-bacterium. It treats & prevents diarrhea, helps in food breakdown and
absorption of nutrients.
Following changes lead to the formation of curd from milk:

 A small amount of curd (starter) is added to milk

 Lactobacillus (present in curd) converts sugars in milk (Lactose) into lactic acid
 Lactic acid imparts sour taste to curd
 Increased acidity causes milk proteins (casein) to turn into solid masses. This changes the texture
of curd.

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Microbes’ role in Baking

Yeast is used as a raising agent in baking. Most commonly used yeast is Saccharomyces cerevisiae .It is
due to the action of yeast that the dough rises, if you leave it for sometime adding yeast to it during
kneading.

Dough (Flour) contains carbohydrates. Yeast when added to it, converts carbohydrates into CO2. Due
the formation of CO2, the dough rises. While preparing cake/ bread, the dough is baked. Once baked, the
yeast dies. As a result, a soft and spongy baked product is formed.
Microbes also play a vital role in fermenting idli/dosa batter. Idli/ dosa batter contain Urad pulses. These
Urad seeds contain Lactic Acid Bacteria (LAB). These bacteria lead to the formation of Lactic acid and
CO2. Formation of Lactic acid gives a sour taste to the batter. Therefore, the batter should not be
fermented for too long, else it might turn too sour.

Microbes’ role in Antibiotics preparation

Microbes are also used to prepare antibiotics, which are used to treat several bacterial infections.
Antibiotics are chemical substances that kill disease-causing microbes. It is quite interesting to find that
there are some microbes which cause diseases; on the other hand, some other microbes help in
preparation of antibiotics, and thus, cure diseases.

Alexander Fleming, a Scottish scientist discovered the first antibiotic & named it ‘Penicillin’.
Penicillin discovery was ‘a chance’ discovery. Fleming was experimenting with Staphylococcus
bacteria. A petridish (cell culture dish) had been left open by mistake, was found to be contaminated by
blue-green mold. This visible mold growth inhibited bacterial growth around itself.

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Fleming concluded that mould released a substance that inhibited bacterial growth. This substance was
the antibiotic which was named ‘Penicillin’ after the mold Penicillium notatum.

 Penicillin was named after Penicillium notatum

 Role of Microbes in Vaccination

 Vaccination is a process in which vaccine is given to improve the immunity of the body against a
specific disease. Vaccine is a biological preparation that resembles a disease causing microbe.
These vaccines are made up of dead or very weak microbes.
 In vaccination, a memory of the disease causing organism is created inside the body, so that the
body can fight back any further attack of the same disease-causing organism. Vaccine is
introduced into the body which resembles a disease-causing organism, at the same time, very
mild to cause any harm to the body. The body produces Antibodies in response to the vaccine.
These Antibodies fight any further attack of the Antigen.
 Antigen refers to any foreign substance inside the body. These can be chemicals, micro-
organisms (bacteria, virus etc), Toxins, Pollen etc. Antigens trigger immune system to produce
antibodies. Antibodies recognize & neutralize pathogens. Each antibody binds to a specific
antigen.

 Vaccination has been a huge success. Diseases like small pox are eradicated. Many diseases like
polio, tetanus, and measles have been reduced to a large extent.
 Role of microbes in production of Beverages
 Yeasts play an important role in the production of various alcoholic drinks. Saccharomyces
cerevisiae is popularly termed as Brewer’s yeast.
 Saccharomyces cerevisiae ferment fruit juices & malted cereals. Molecules like glucose, fructose
and sucrose are converted into C2H5OH and CO2 and release energy. Yeasts perform this
conversion in absence of oxygen.
 C6H12O6 --> 2C2H5OH + 2CO2
 This reaction takes place in presence of enzyme Zymase. Alcohol (Ethanol) is produced as a
result if this reaction. CO2 released is used as raising agent in making bread.
Role of Microbes in preparation of chemicals
Several chemicals are produced by Microbes like organic acids, enzymes and alcohol. Some of the
examples of microbes which produce various organic acids are as follows:

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 Lactobacillus Lactic acid

 Acetobacter aceti Acetic acid
 Clostridium butylicum Butyric acid
 Aspergillus niger Citric acid
Microbes as Biofertilizers
Fertilizers are substances added to enhance the soil fertility. This results in higher yields & healthier
plants. Chemical fertilizers, however have several disadvantages like they are toxic to various life
forms, can cause imbalance in soil ph, results in soil infertility, degrades ecosystem, plants become
susceptible to many diseases, fruits & vegetables have high toxic residues. Excessive use of fertilizers
can cause environmental pollution.

Use of biofertilizers is preferred as they do not include any of the disadvantages mentioned above.
Biofertilizers are living organisms that enrich the soil nutrient quality. Some of the sources of
biofertilizers are bacteria, fungi, cyanobacteria etc.
Rhizobium, is an example of a nitrogen fixing bacteria present in the root nodules of leguminous plants.
Nitrogen is a macronutrient for the growth & development of plants. Rhizobium enriches soil with
nitrogen.
Mycorrhiza, a symbiotic association between fungi & certain plants, also enhance the phosphorus
content which in turn helps in better growth & development of plants. They are
Nitrogen Cycle
Nitrogen cycle is all about the movement of nitrogen between various elements on Earth (like air, soil,
living organisms etc.) The amount of nitrogen in the atmosphere remains constant.

 Atmosphere has approx. 78% nitrogen.

 Atmospheric Nitrogen is fixed into the soil
o N2 fixing microbes convert atm. N2 into nitrogen compounds like NH3
 Plants utilize nitrogen from soil through their roots
 Animals utilize nitrogen, feeding on plants
 When Plants & animals die, Nitrogenous wastes are returned to soil
o Decomposers convert some part to nitrogen compounds to be used by plants
o Denitrifying bacteria convert into atm. N2

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Microbes as Decomposers
Decomposition is the Process in which complex organic matter is broken down into simpler forms. This
process breaks down dead & decaying organic matter into simple inorganic forms.

Organisms which help in decomposition are termed as ’Decomposers’. Bacteria & Fungi are important
Decomposers.
Decomposers help the environment to get rid of dead & decaying matter and also enrich the soil quality
for better growth of plants.
Harmful Micro-organisms
There are many microbes which cause several diseases in plants, animals & human beings. Such
disease-causing organisms are called Pathogens. Pathogens include bacteria, viruses, fungi & protozoa.

In this section, we will discuss about the various diseases caused by various pathogens. ‘Disease’ is a
disturbed ease. Disease results in a change in either the functioning or the appearance of one or more
systems of the body for worse.
Diseases in Humans: Typhoid

 Pathogen
o Bacteria, Salmonella typhi

 Pathogen’s entry

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oContaminated food & water

oPrimarily reach small intestine
Symptoms

o High fever
o Headache
o Weakness
o Stomachache
o Constipation
o Loss of appetite

 Treatment
o Diagnosed using Blood culture/ Urine culture or Widal test
o Treated with a course of antibiotic medication
Diseases in Humans: Pneumonia

 Pathogen
o Bacteria, Streptococcus pneumoniae
o Bacteria, Haemophilus influenzae

 Pathogen’s entry
o Through contaminated air
o Inhalation of droplets released by infected person
o Primarily reach lungs
o Alveoli gets infected

Symptoms

o High fever
o Chills
o Cough
o Short of breath
o Headache
o Bluish lips & finger nails
o Weakness

 Treatment
o Diagnosed using Urine test/Mucous test/ Chest X-ray
o Treated with a course of antibiotic medication
Diseases in Humans: Common Cold

 Pathogen
o Viruses (e.g: Rhino virus)

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 Pathogen’s entry
o Through contaminated air/ objects
o Inhalation of droplets released by infected person
o Nose & respiratory passage gets infected
o Lungs remain unaffecte

 Symptoms
o Sore throat
o Cough
o Headache
o Nasal congestion
o Nasal discharge
o Hoarseness

 Treatment
o Treated with medication like pain killers, cough syrups or nasal sprays
o Antibiotics do not help a viral infection
Diseases in Humans: Malaria

 Pathogen
o Protozoa, Plasmodium
(P. vivax, P. falciparum, P. malaria

 Pathogen’s entry
o Through bite of female Anopheles mosquito
o Female Anopheles mosquito acts as Transmitting agent
o RBCs are ruptured

 Symptoms
o High fever
o Chills
o Headache
o Bodyache
o Nausea
o Vomiting

 Treatment
o Diagnosed using Blood tests & Liver Function tests
o Treated with anti-malarial drugs
Lifecycle of Malarial parasite
Plasmodium parasite has 2 hosts. This parasite spends half of its lifecycle inside
human beings & the remaining half inside mosquitoes. Thus, Humans &
mosquitoes are two hosts of Plasmodium parasite.

1. Mosquito bites an infected person

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2. Takes up gametocytes
3. Development of gametocytes occurs in mosquito
4. Sporozoites are formed & stored in salivary glands of mosquitoes
5. The same mosquito then bites a normal person
6. Injects the sporozoites
7. Development of the sporozoites occur in liver cells inside the body of that
person
8. RBCs rupture, the person thus suffers from malaria
9. Gametocytes are formed, which get picked up by mosquitoes when they
bite this person again.

Diseases in Humans: Cholera

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 Pathogen
o Bacteria, Vibrio cholerae

 Pathogen’s entry
o Contaminated food & water
o Pathogen releases toxin in intestine

 Symptoms
o Watery diarrhea
o Vomiting
o Dehydration
o Weakness
o Muscle cramps
o Thirst

 Treatment
o Oral/ intravenous solutions to compensate for dehydration
o Extreme cases can be treated with antibiotic medication
Diseases in Humans: Measles

 Pathogen
o Virus, paramyxovirus

 Pathogen’s entry
o Transmitted through droplets from nose/ throat/ mouth
o Highly infectious
o Children are more prone to infection

 Symptoms
o Dry cough
o Watery eyes
o Sneezing
o Mild fever

 Treatment
o Treated with medication like cough syrups, paracetamol or Vitamin A supplements
o Antibiotics do not help a viral infection
Diseases in Humans: Chicken pox

 Pathogen
o Virus, varicella

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 Pathogen’s entry
o Transmitted through droplets from sneeze/cough or contact
o Highly infectious as long as rashes exist

 Symptoms
o Itchy rash
o Fever
o Loss of appetite
o Headache
o Cough
o Sore throat

 Treatment
o Treated with anti-viral; drugs
o Antibiotics do not help a viral infection
Prevention of Infectious diseases in Humans
As is rightly said “Prevention is better than cure”, we should take care of the following things to
prevent the spread of infectious diseases.

 Maintain Personal cleanliness

 Ensure Clean drinking water
 Wash vegetables & fruits before consumption
 Proper disposal of excreta
 Avoid stagnation of water
 Use mosquito repellents
 Spraying insecticides in drainage areas
Diseases in Animals: Foot & Mouth disease

 Pathogen
o Virus (7 types exists)

 Pathogen’s entry
o Transmitted through saliva, mucus, milk or faeces
o Infection spreads through inhalation/ ingestion / direct contact
o Common in cattle, pigs, sheep

 Symptoms
o Fever
o Decreased milk production
o Weight loss
o Loss of appetite
o Lameness

 Treatment
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o Completely treated if medication given at an early stage

o Vaccination available for prevention against certain stains of pathogen
o
Diseases in Animals: Blackquarter

 Pathogen
o Bacterium, Clostridium chauvoei

 Pathogen’s entry
o Transmitted through soil/ food
o Infection progresses extremely fast
o Sometimes, survival only up to a couple of hours after symptoms are seen
o Common in cattle, sheep, goats
 Symptoms
o Fever
o Swelling of limbs
o Lameness
o Inflammation of skeletal muscles

 Treatment
o Completely treated only if medication is given at an early stage
o Treated with antibiotics (penicillin)
o Effective vaccine provides protective immunity
Prevention of Infectious diseases in animals
Following things should be taken care to prevent the spread of infectious diseases in animals:

 Proper feeding of cattle

 Maintain hygiene
 Regular checkup by veterinary doctor
 Isolation of an infected animal
 Timely vaccination of animals
Diseases in Plants: Rust of Wheat

 Pathogen
o Pucciniarust fungus
 Puccinia triticinacauses 'black rust',
 reconditacauses 'brown rust'
 striiformiscauses 'Yellow
rust'

 Pathogen’s entry
o Transmission via soil through infectious spores

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 Symptoms
o Small elevated structures (pustules) on leaf blades
o Patches formed in extreme cases
o Pustules on stems

 Treatment
o Applying fungicides at an early stage can be helpful
Diseases in Plants: Late blight of potato

 Pathogen
o Fungus-like organism, Phytophthora
infestans

 Pathogen’s entry
o Infectious spores transmitted by water/ wind
o Wet/ humid conditions favor infection
o Affects potato, tomato etc

 Symptoms
o Potato leaf lesions
o Reddish brown discoloration of potato tuber
o Brown lesions on stem

 Treatment
o Applying appropriate fungicides at appropriate time can be helpful
Diseases in Plants: Citrus Canker

 Pathogen
o Bacterium, Xanthomonas axonopodi

 Pathogen’s entry
o Entry through stomata/ wounds on leaves
o Infection can spread through rain/ wind or contaminated equipments
o Affects citrus plants

 Symptoms
o Premature fall of leaves
o Lesions on leaves, stems & fruits
o Premature drop of fruit

 Treatment
o No specific treatment procedure so far
o Citrus farming becomes difficult & expensive

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Diseases in Plants: Powdery mildew

 Pathogen
o Fungi
o Many species of order
Erysiphales

 Pathogen’s entry
o Infectious spores are transmitted through wind
o Sensitive to extreme heat & sunlight
o Affects many crops like beans, beet, carrot, lettuce, melons, peas etc..

 Symptoms
o White powdery covering
o Leaves curl
o Appearance of lesions
o Colored patches on leaves/ stems/ fruits

 Treatment
o Applying fungicides/ oils/ sulfur can treat the disease
Food Poisoning
Food can be poisoned by microbes. Microbes produce toxic substances and thus, poison/ spoil the food.
Consuming spoiled food can make us ill. Therefore it is very important to preserve food items so that
microbes cannot grow & spoil them.

Microbes just don’t attack any food item, they need a suitable environment to grow & survive. Only
then, they can release toxic substances and thus spoil the food. Some factors which promote growth of
microbes are moisture, warm temperature etc.
Let us now talk about how we can preserve food to protect them from microbes
Food preservation techniques
There are various techniques of food preservation like using chemicals, salt, vinegar, sugar, oil etc. Heat
& cold treatment also helps to preserve food. Proper storage is very important for preservation of food.
Preserve by chemicals
Chemicals prevent attack & growth of microbes. Some examples are as follows:

 Sodium benzoate
o Fruit juices, syrups, jams, jellies

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 Sodium metabishulphite
o Dried fruits/ vegetables, syrups, fruit juices
 Acetic acid (Vinegar)
o Pickles, sauces, ketchup
 Sodium chloride (Salt)
o Meat, Amla, raw mango, fish
 Oils
o Ph is such that spoilage bacteria can’t survive
o Fried food, pickles
 Sugar
o Reduce moisture content, therefore inhibit bacterial growth
o Jam, Jelly, Squash

Food should be stored in proper sealed packets or air tight containers. Microbes need moisture, air etc.
for growth. Therefore, such containers would inhibit their growth.

Preservation by Heat & Cold treatment

 Food item can be heated to destroy micro-organisms that can otherwise spoil the food
 An example of heat treatment is Sterilization.
Sterilization is a process in which food is heated to a high temperature (greater than 100oC) for a
sufficient time. In this method, both the container & content are sterilized.
For example, Feeding bottles of babies are sterilized to keep it free from germs.

Not only heat, cold temperatures also prevent growth of spoilage bacteria. That is why, bread kept
inside a refrigerator lasts longer than the one kept at room temperature.

Pasteurization is a technique that makes use of heat & cold treatments to preserve food items. In this
process, milk is heated to about 700C for 15-30 sec & then suddenly chilled & stored. This technique
was invented by Louis Pasteur (1864).

This technique destroys pathogens in milk, and reduces the number of spoilage microbes. Thus, it
increases shelf life of milk.
अब सबका summary Hinglish मे देता हूँ
🔍 What are Microorganisms? (सूक्ष्मजीव क्या हैं?)
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Microorganisms (सूक्ष्मजीव) are tiny living organisms that cannot be seen with the naked eye.
ये इतने छोटे होते हैं कि microscope की मदद से ही देखे जा सकते हैं।
They are found in air, water, soil, food — everywhere!
👉 Main Types of Microbes:
Microbe
Nature & Shape (स्वरूप) Examples (उदाहरण)
(सूक्ष्मजीव)
Bacteria Unicellular, spherical/rod-shaped Lactobacillus, Salmonella
Fungi Multicellular (mostly) Yeast, Penicillium, Molds
Protozoa Unicellular, aquatic Amoeba, Plasmodium
Algae Photosynthetic, aquatic Spirogyra, Chlamydomonas
Virus Non-living outside host Flu virus, COVID-19, HIV
📌 Note: Viruses reproduce only inside living cells.

💡 Helpful Microorganisms (लाभकारी सूक्ष्मजीव)

🧀 1. In Food Industry:
 Lactobacillus ➤ Converts milk to curd. (दूध से दही बनाता है)
 Yeast ➤ Used in baking bread and fermentation (alcohol making).
 Saccharomyces cerevisiae ➤ Brewer’s yeast for wine & beer.
💊 2. In Medicine:
 Penicillin ➤ First antibiotic, discovered by Alexander Fleming from Penicillium fungus.
 Used to kill disease-causing bacteria (बैक्टीरिया को मारता है).
🧬 3. In Vaccine Production:
 Vaccines contain dead/weak microbes ➤ stimulate antibody production.
 Example: Polio, Measles, Hepatitis vaccines.
🌱 4. In Agriculture:
 Rhizobium ➤ Lives in legume roots, fixes atmospheric nitrogen (नाइट्रोजन स्थिर करता
है)
 Cyanobacteria (e.g. Anabaena) ➤ Blue-green algae → nitrogen fixation
♻️5. As Decomposers:
 Bacteria & fungi ➤ Decompose dead matter → enrich soil fertility.
 Nature की सफाई करते हैं और nutrients recycle करते हैं।

❌ Harmful Microorganisms (हानिकारक सूक्ष्मजीव)

👨‍⚕️Human Diseases:
Disease Microbe Type Pathogen Spread By
Typhoid Bacteria Salmonella typhi Contaminated food/water
Cholera Bacteria Vibrio cholerae Unhygienic conditions
Malaria Protozoa Plasmodium Female Anopheles mosquito
Common Cold Virus Rhinovirus Airborne droplets
Measles Virus Paramyxovirus Cough/sneeze droplets
🐮 Animal Diseases:
 Foot & Mouth Disease – Virus
 Anthrax – Bacteria

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🌿 Plant Diseases:
Disease Microbe Type Causative Agent
Rust of Wheat Fungus Puccinia
Citrus Canker Bacteria Xanthomonas
Late Blight (Potato) Fungus-like Phytophthora infestans

🍱 Food Preservation Techniques (भोजन संरक्षण के तरीके)

Method Use/Example
Salt Amla, Pickle, Fish
Sugar Jam, Jelly – reduces moisture
Oil/Vinegar Pickles – blocks air & bacteria
Refrigeration Slows down bacterial growth
Pasteurization Milk is heated to ~70°C & then cooled – kills germs
Chemical Preservatives Sodium benzoate in squashes, juices

🔁 Nitrogen Cycle (नाइट्रोजन चक्र)

Steps:
1. Nitrogen Fixation – Rhizobium bacteria fix atmospheric N₂ → NH₃
2. Nitrification – Ammonia → Nitrites → Nitrates
3. Assimilation – Plants absorb nitrates
4. Ammonification – Dead matter → Ammonia
5. Denitrification – Nitrates → N₂ gas (returns to air)
🔄 यह cycle environment में nitrogen का balance बनाए रखता है।
कुछ न समझ आये तो पूछ लेना 9455857477

Unit -3 Conservation of animal and Plant

Introduction
 A large variety of plants and animals found on our planet. They both depend on each
other for survival. So, we need to conserve biodiversity as it helps in balancing the
ecosystem.
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 Conservation can be defined as the protection and maintaining of diversity of

species (plants and animals).
 Conservation includes the protection of species from extinction and restoring
habitats, preventing deforestation and enhancing ecosystems.
 Today, a major threat to survival of mankind is deforestation.
Deforestation
The term deforestation can be defined as the act of massive cutting down of trees and clearing
of forests to use the land for agricultural purposes. Deforestation disturbs the balance in

nature. If cutting of trees continues, rainfall and the fertility of the soil will decrease.
Reasons or causes of deforestation
1. Rapid urban development
2. Setting up industries
3. Agricultural related purposes
4. Making furniture
5. Using wood as a fuel.
6. Natural causes such as Forest fires, Droughts, Acid rains and Volcanic
eruptions.Figure below shows the points you must remember for the causes/reasons
of deforestation

Consequences of deforestation
Deforestation causes severe impact on the environment such as
 Loss of habitat This leads to the extinction of many of species. Due to deforestation
forests are vanishing due to animals are losing their habitat.
 Rise in temperature The increase in temperature on the earth disturbs the water
cycle and may reduce rainfall which cause drought.
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 Depletion of ground table.

 Global warming Plants absorb carbon dioxide from the environment for the purpose
of photosynthesis but due to deforestation the amount of carbon dioxide has
increased in environment due to which global warming has increased. Increased
global warming has disturbed rainfall patterns.
 Less exchange of gases between green plants and the environment.
 Desertification Deforestation increases the soil erosion which leads to deterioration
of fertile land. Soil erosion is the removal of top layer of the soil and exposes the
lower, hard and rocky layers which contain less humus and is less fertile. Gradually,
the fertile land gets converted into infertile (barren) land or wasteland. So,
desertification can be defined as a gradual conversion of fertile land into wasteland.
Biodiversity
The variety of living organisms like plants,animals and micro-organisms is called biodiversity.
In other words it refers to the vast variety of life on Earth. Any living thing, including plants,
bacteria, animals, and humans, is included in the term biodiversity.
Conservation of biodiversity
The conservation of biodiversity is important as it maintains the ecological balance on the
earth. It also maintains the soil fertility or prevents soil erosion.
What is meant by biodiversity conservation?
The protection, restoration, and management of ecosystems and natural environments, as well
as ensuring that they are safe and functional, are all part of biodiversity conservation.
How can we conserve biodiversity
Biodiversity can be conserved by
 Not cutting trees.
 Not hunting animals.
 Utilizing natural resources in a cost-effective manner.
 Creating protected areas for animals like wild life centuries, where no human
activities are permitted.
Flora and Fauna
1. Some plants and animals are found in particular areas.

2. They may not exist naturally in other locations.

3. The 'plants' that grow naturally in a specific area are referred to as the 'flora' of that
area. Teak, Jamun, Fern, (Sal) Mango and Arjun are the flora of Pachmarhi
Biosphere Reserve
4. And the 'animals' that live naturally in a specific area are referred to as the 'fauna' of
that area.
5. Thus, flora and fauna refer to plants and animals that grow naturally in that region.
Cheetal, Wolf, Leopard, Chinkara, Blue bull, Barking deer, and Wild dog are the
examples of fauna of the Pachmarhi Biosphere Reserve

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6.
Difference between flora and fauna
Flora-
1. The plants found in a particular area are called flora.
2. Example-Peepal, sal, banyan.
3. Flora is non-motile (not capable of motion) and synthesize its own food.
Fauna
1. The animals found in a particular area are called fauna.
2. Example-Deer, Panda
3. Fauna is motile (capable of motion) and can move from one place to another for food.
Species
Organisms that resemble one another having common characteristics and are able to breed
among themselves are called a species. Species is a group of population which are capable of
interbreeding. Members of species have common characteristics.
Wildlife species on the basis of being threatened or extinct are being classified into different
categories such as
 Endemic species
 Extinct species
 Endangered species
 Threatened species
Endemic Species:- Those species which are restricted to a particular region or area are
called endemic species. For example-Tree like sal and animals like gibbon.
Extinct species:- Those species which no longer exists anywhere on the earth are called
extinct species.
Endangered species:- Those species which are on the urge of extinction are called
endangered species. For example-Leopard, Giant panda. Habitat Destruction is the main
reason that many species are becoming endangered.
Threatened species:- Those species which are in danger of extinction are called threatened
species. For example- Black buck, elephant.
Migration
 It can be defined as a movement of a species from its own habitat to another habitat.
 Several species of birds, fish, deer, monarch butterflies, green turtles move from one
region to another
 With weather changes (especially cold) for food, breeding and to avoid unfavourable
conditions.
 In India, migratory birds from the Arctic and northern regions are found.
 They have a natural habitat in Siberia which is a very cold place.

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 When the winter ends, the Siberian cranes fly back to their homeland.
Ecosystem
 The biotic factors such as (plants, animals and humans) and Abiotic factors (soil,
water, air) together constitute the ecosystem.
 The various living organisms in an ecosystem interact with one another (via food
chains) as well as with the physical environment in which they exist.
 An ecosystem is an autonomous unit of live organisms and a non-living environment,
which only requires sunlight to function.
Importance of forests
Forests are of great importance to the living beings. Given below are some of the points that
shows how important forests are for mankind
 Forests aid in the conservation of biodiversity.
 Forests are naturally occurring environments for a variety of plants and animals.
 Forests provide a variety of resources such as timber, wood, food, medicines, and
fodder.
 Forests contribute to the preservation of ecological balance.
 Forests contribute to the regulation of climate and rainfall.
 Forests aid in soil erosion prevention and flood protection.
 Forests play an important role in providing the oxygen to the world.
Need of conservation of species
To protect the plant and animal species from being extinct there is a need for conservation.
Some of the reasons for the need of conservation of species are
1. To maintain and preserve the eco-system.
2. The genetic diversity must be sustained.
3. The growth of tourism which might help to keep the economy growing.
4. Food resource conservation.
5. Medicinal use for human benefit.
6. To preserve endangered, uncommon, and vulnerable species.
Red Data Book
Based on the risk of endangered and extinction, the IUCN (The International Union for the
Conservation of Nature and Natural Resources) maintains a list in a book called the Red Data
Book which classifies animals and plants into different groups. Red Data Book keeps a record
of all the endangered animals and plants. Red Data Book is maintained internationally by an
organism. Our country also maintains Red Data Book for plants and animals.
Project Tiger
Project Tiger was launched in the country by the government in 1973 to protect the Bengal
Tiger. The objective of this project was to ensure the survival and maintenance of tiger
population. Project Tiger's main aims are to:
 Reduce the factors that contribute to tiger habitat loss and reduce them by
appropriate management.
 The habitat damage must be repaired to the greatest degree possible in order to
promote the ecosystem's recovery.
 Maintaining a viable tiger population is important for economic, science, cultural,
aesthetic, and ecological reasons.
Conservation of forests and wildlife
For conservation of forests and wildlife, the government has set up protected areas such as-
wildlife sanctuaries, national parks, biosphere reserve and biodiversity parks. Cultivation,
grazing, cutting trees, hunting and poaching are strictly prohibited in these protected areas.
Biosphere reserves

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 Biosphere reserves are the extended protected land meanat for the conservation of wild animals
and plants.
 It is also meant to restore the traditional life of the tribals residing in the the area.

 The biosphere reserves maintains the biological diversity of an area.

 The Biosphere Reserves of india are as follows:

Biosphere Reserve State

Great Rann of Kutch Gujarat

Gulf of Mannar Tamil Nadu

Sunderbanas West Bengal

Cold Desert Himachal Pradesh

Nandadevi Uttarakhand

Nilgiri Tamil Nadu, Kerala, Karnataka

Dehang-Dibang Arunachal Pradesh

Panchmarhi Madhya Pradesh

Seshachalam Hills Andhra Pradesh

Similipal Odisha

Achanakamar-Amarkantak Madhya Pradesh

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Manas Assam

Khangechendzonga Sikkim

Agasthyamalai Kerala, Tamil Nadu

Great Nicobar Andaman and Nicobar Island

Nokrek Meghalaya

Dibru-Saikhowa Assam

Panna Madhya Pradesh

Wildlife sanctuary

 Wildlife sanctuaries are the regions where animals kept protected from any sort of disturbance to
their habitat and their surroundings.
 They are also aimed at providing suitable and comfortable living conditions to the animals.
Killing, poaching or capturing of animals is strictly prohibited in these regions.
 The sanctuaries in India have beautiful and unique landscapes, dense forests, bushes in the delta
of big river and mountain forests to protect ythe animals in their natural habitat.

 Animals like black buck, white eyed buck, elephant, golden cat, gharial, marsh crocodile,
rhinoceros, python, etc. are some of the threatened animals are protected and conserved in the
wildlife sanctuaries.

Wildlife Sanctuary State

Bharatpur Bird Sanctuary Rajasthan

Chilika Lake Bird Sanctuary Chilika

Mudumalai Sanctuary Tamil Nadu

Chinnar Wildlife Sanctuary Kerala

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Periyar Wildlife Sanctuary Kerala

Govind Wildlife Sanctuary Uttarakhand

Gir National Park and Wildlife Sanctuary Gujarat

National park

 National parks are also established for the protection of flora and fauna.

 They are protected areas intended to provide a natural habitat with all natural resources to the
animals where they can freely roam and use the habitat.
 These areas are extended and diverse enough to protect the entire ecosystem including the flora,
fauna, historic objects and the natural landscapes.
 The National Parks of India are as follows:

National Park State

Ranthambhore National Park Rajasthan

Corbett National Park Uttarakhand

Bandhavgarh National Park Madhya Pradesh

Periyar National Park Kerala

Kaziranga National Park Assam

Sunderbans West Bengal

Kanha National Park Madhya Pradesh

Reforestation
 Reforestation is the opposite of deforestation.

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Reforestation can be defined as the process of replanting trees and recreation of forests which
have been destroyed in the past.
 For this people should be encouraged to plant more and more trees.
 Reforestation can take place naturally also. If the deforested area is left undisturbed,
it re-establishes itself.
 In India we have the Forest Conservation Act. This act is aimed at preservation and
conservation of natural forests and meeting the basic needs of the people living in or
near the forests.
Recycling of paper
 Recycling of paper refers to the process by which waste papers can recycled for
reuse.
 Recycling one tons of paper can save around 17 fully grown trees from being cutting
down and also saves landfill space.
 It saves energy.
 The amount of harmful chemicals used in paper making will also be reduced.
अब इसका summary Hinglish में दे रहा हूँ
🌳 Forest & Wildlife Conservation (वन और वन्यजीव संरक्षण)
🔰 Introduction
🟢 हमारे ग्रह पर लाखों species के plants और animals मौजूद हैं। वे एक-दूसरे पर
निर्भर हैं।
🟢 यदि किसी एक का संतुलन बिगड़ा – पूरा ecosystem disturbed हो जाता है।
👉 Conservation = जीवों की सुरक्षा + उनका आवास (habitat) संरक्षित रखना।

🌲 Deforestation (वनों की कटाई)

Deforestation = पेड़ों की कटाई large scale पर → खेती, industry, development के लिए।
🚨 Causes (कारण):
1. शहरीकरण (Urbanization)
2. Agriculture + लकड़ी की ज़रूरत
3. Forest fires, droughts, volcanic eruption
⚠️Effects (प्रभाव):
 Habitat loss ➤ कई species extinct हो जाती हैं
 Global warming ➤ CO₂ बढ़ता है
 Desertification ➤ उपजाऊ ज़मीन → बंजर
 Rainfall कम होती है, water table गिरता है

🧬 Biodiversity (जैव विविधता)

Biodiversity = variety of plants, animals, microbes etc.
🌱 It ensures food chains, ecosystem services & ecological balance.
📌 Conservation of Biodiversity means:
 Forests ना काटना
 जानवरों का शिकार रोकना
 Wildlife sanctuaries बनाना
 Resources का सही उपयोग

🌿 Flora & Fauna

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शब्द अर्थ उदाहरण

किसी क्षेत्र पीपल, साल, आम,
Flora
के पौधे अर्जुन
किसी क्षेत्र चीतल, भेड़िया,
Fauna
के जानवर नीलगाय
📍 Example: Pachmarhi Biosphere Reserve
Flora – साल, जामुन Fauna – वाइल्ड डॉग, चीतल

🧬 Species & Classification

Type Meaning Example
केवल एक region में पाए
Endemic species गिबन, साल
जाते हैं
पूरी तरह खत्म हो चुके
Extinct species डायनासोर
हैं
Endangered species लुप्त होने की कगार पर Giant Panda
Black buck,
Threatened species खतरे में
हाथी

🦅 Migration (प्रव्रजन)
🔁 जब जानवर/birds एक habitat छोड़कर दूसरे में जाते हैं – उसे migration कहते हैं।
Example: Siberian Cranes – हर साल ठंड में भारत आते हैं।

🌍 Ecosystem
Ecosystem = Biotic (living) + Abiotic (non-living) का interaction
➡️Food chains, balance of gases, rainfall, temperature – सब ecosystem का हिस्सा है।
📌 Ecosystem को बचाने के लिए forests, rivers, soil, animals को conserve करना ज़रूरी है।

🌳 Importance of Forests
 Oxygen supply करते हैं
 Flood & soil erosion रोकते हैं
 कई animals का घर होते हैं
 Medicines, wood, fodder का source
 Biodiversity conserve करते हैं

📘 Red Data Book

 Maintained by IUCN
 Lists all endangered/extinct plants & animals
 India also maintains separate Red Data Books

🐯 Project Tiger (1973)

🎯 Aim: Bengal Tiger को protect करना
✅ Objectives:
 Habitat loss को रोकना
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 Population बढ़ाना
 Ecosystem restore करना

Protected Areas
🟢 Biosphere Reserves
 Large areas: animals, plants + tribal culture को conserve करते हैं
 Examples:
o Nilgiri (TN, Kerala, Karnataka)
o Sundarbans (WB)
o Panchmarhi (MP)
🟠 Wildlife Sanctuaries
 Animals को hunting/poaching से बचाते हैं
 Example: Bharatpur (Rajasthan), Periyar (Kerala), Gir (Gujarat)
🔵 National Parks
 Flora & Fauna दोनों की protection
 Example: Kaziranga (Assam), Corbett (Uttarakhand), Kanha (MP)

🌱 Reforestation & Recycling

🌳 Reforestation:
 पेड़ दोबारा लगाना
 Naturally भी possible है
 Forest Conservation Act – forests को preserve करता है
♻️Paper Recycling:
 1 ton paper = 17 पेड़ बचते हैं
 Energy बचती है
 Pollution कम होता है

कुछ न समझ आये तो पूछ लेना 9455857477

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Unit – 4 Reaching at the age of Adolescence

Introduction
 The word adolescence means to grow into adulthood.
 Adolescence can be defined as the period of growth during which a child develops
into an adult.
 The period of adolescence begins around the age of 10 -11 years and continues till
18-19 years of age. Growing up is a natural process.
 It is the period between puberty and adulthood in human development.
 In this time period, the body undergoes different changes alongside reproductive
maturity .
 Adolescents are also called teenagers because the period covers the teens thirteen
to nineteen years of age .
 In girls, adolescence may begin a year or two earlier than in boys. The period of
adolescence varies from person to person. It is a stage of rapid growth and
development.
 When the human body undergoes several changes during the adolescence ,it Mark’s
the onset of puberty.

 Puberty can be defined as the process of physical changes by which a child becomes
an adult and is capable of reproduction.
 The capability of reproduction is the most important change which marks the puberty.

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Changes that mark adolescence

1. Growth Spurt
2. Change in body shape.
3. Change in voice
4. Increased activity of sweat and sebaceous gland
5. Development of sex organs
6. Reaching mental, intellectual and emotional maturity.
7. Development of secondary sexual characters.

The above mentioned changes that mark adolescence are explained below

1. Growth spurt
 Growth spurt can be defined as a sudden increase in height. At this time bones of the
arms and legs elongate and make a person tall.
 The following chart gives the average rate of growth in height of boys and girls

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2.
Change in body shape
1. In boys
o Broader shoulder
o Wider chests
2. In girls
o Region below the waist becomes wider.

3. Changes in voice


 At the time of puberty the change of voice takes place in girls and boys.In boys the
larynx grow larger at the time of puberty and can be seen as protruding part of

throat.This protrusion is called Adam's apple.<

 Protruding voice box in boys is called Adam's apple.
4. Increased activity of sweat and sebaceous gland (Oil gland)
 A temporary condition in which young people get pimples and acne on the face due
to increased activity of these glands in the skin but disappears by the time they
become adults.
5. Development of sex organs
 Production of sex hormones that stimulate gamete production.
 In boys:- Male sex organs like the testes and penis develop completely. Testes
begins to produce sperm.

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 In girls:- The ovaries enlarge and egg begins to mature. Ovaries start releasing
mature egg.
6. Reaching Mental, Intellectual and Emotional Maturity
 They become more independent than before.
 They become self conscious.
 Develop a way of thinking.
 This is that time when brain has the greatest capacity for learning.
7. Development of secondary sexual characters
 Secondary sexual characters can be defined as the characters or features which help
to distinguish the male from the female.
 These characters develop by the secretion of chemical substances called hormones.
 Testosterone is the male hormone released by testes whereas the oestrogen is the
female hormone released by ovaries.
 Boys develop the following secondary sexual characters
1. Facial hair.
2. Body hair, prominently under arm, abdomen, chest, pubic hair.
3. Deep voice
4. Beard, Moustaches developed.
 Girls develop the following secondary sexual characters
1. Region below the waist becomes wider.
2. Body hair, prominently in armpits and pubic hair.
3. Development of mammary glands inside the breast.
4. Beginning of menstrual cycle.
5. Shrilled voice
Hormones
 Also known as chemical messengers.
 Hormones are chemicals secreted by specialized gland called endocrine gland.
Endocrine glands are also called ductless gland as they pour their secretions directly
into the blood stream and reach parts of the body(Target site).
 The production of hormones is under the control of another hormone secreted from endocrine gland
called pituitary gland.
 Pituitary gland is also called as master gland.
Hormones other than sex hormones
Hormones secreted by the endocrine glands.

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Position of various glands in Human Body

Reproductive phase of life in humans

Hormones from pituitary gland stimulate testes and ovaries to release testosterone in males
and Oestrogen in females and released in the blood stream and reach the parts of body
(Target site).It stimulate the changes in the body at onset of puberty.

In the female body, the reproductive phase of life starts at puberty. The process can be
explained as follows
 The ova begin to mature with the onset of puberty. One ovum matures and is
released by one of the ovaries in 28 or 30 days .This is called ovulation. This cycle
repeats every month and is known as menstrual cycle. The whole process is known
as menstruation.
 Menstruation can be defined as shedding of the unfertilized egg along with the
thickened lining of the uterus and its blood vessels from a female body on a monthly
basis and commonly called periods.
 The first menstruation occurs at the onset of puberty and beginning of the menstrual
cycle is called menarche.
 Whereas, pause of the menstrual cycle in females at the age of 45 – 50 years is
called menopause .
Menstrual cycle in females
When girls reach the age of adolescence they enter into the age when they are capable of reproduction.
The reproductive age in girls begins right form the age of 10 to 12 years and ends at the age of 45 to 50
years.
At the onset of puberty, the ovaries in girls starts to mature. Every month one ovum gets matured and
then gets released by the ovaries. This procedure happens once in 28 to 30 days approximately.

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At this time of month the uterine wall becomes thick to receive the mature egg. If the egg gets fertilised
and begins to develop it leads to pregnancy.

Fig. Steps involved in pregnancy

But if fertilisation does not occur then the released egg and thick lining of uterus along with blood gets
shed off through the vagina in females.
This leads to bleeding in women at a specific period of month (once in about 28-30 days) and is called
menstruation.
The first menstrual flow in girls once they reach the age of adolescence is called menarche.
The stoppage of menstrual flow at the age of 45-50 years in girls is called menopause.

The menstrual cycle includes following steps:

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 Maturation of eggs
 Release of matured eggs.
 Thickening of the wall of uterus
 Break down of thickened wall of uterus if pregnancy doesnot occur.
 Embedding of fertilised egg in the uterine wall for further development if pregnancy occurs.

Sex determination of a baby

 In human beings, each cell of the body contain 46 chromosomes or 23 pairs of
chromosomes. Out of these,22 pairs of chromosomes are common to both males and
females and are called autosomes. Only one pair is different which is called sex
chromosome.

 The sex of a human is determined by the sex chromosome.

1. In females – XX chromosomes is present.
2. In males – X chromosomes and Y chromosomes is present.
 So, in the process of fertilization, if a sperm containing the X chromosomes fertilizes
the egg containing X chromosomes, the zygote is formed which consists of two X
chromosomes and will develop into a female child.
 Similarly, If a sperm containing the Y chromosome fertilizes the egg containing the X
chromosomes, the zygote formed will have one X and one Y chromosomes which will
develop into a male child.
 It’s clear from the above that sex of a unborn child depends on the type of
chromosomes their father posses.



Reproductive health of adolescents
 Health can be defined as a state of physical, mental well being of an individual.
 During adolescence, nutritional health is very important for supporting the body as it
is growing.
 Adolescence is a stage of rapid growth and development. Hence the diet should be
balanced.

Nutritional needs of adolescence

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 Balanced diet is a diet which contains all the nutrients like carbohydrates, proteins,
vitamins, fats and minerals in a right proportion. Apart from healthy diet ,personal
hygiene and physical exercise is considered most important.

 Personal hygiene refers to the practice of keeping yourself clean as by taking bath
regularly. Bathing is essential due to body odour which is caused by sweat glands.
Poor hygiene can lead to a microbial infection. Girls should also take special care of
cleanliness during the time of period.
 Doing regular physical exercise, can keep the bod healthy and mind calm. It control
body weight as well as control the feeling of anxiety and depression. Physical
exercise includes walking, cycling, doing yoga and playing outdoor games.
Hormones involved in Metamorphosis
 The conversion of larva into an adult by undergoing through drastic
changes is called metamorphosis.
 Let us consider the example of transformation of a tadpole into a frog.


 As a tadpole develops into a frog it looks very different from the late
tadpole and has different properties fom tadpole.
 This process of metamorphosis in frogs is controlled by the thyroid gland
that releases thyroxine in the presence of iodine in water.
 In the absence of iodine in water tadpoles cannot convert from tadpole to
adult frogs.
 Whereas the process of metamorphosis in insects is controlled by the
insect hormones.

Things to avoid during adolescence

Say no to drugs

During adolescence, always stay away from bad habits like smoking, or using narcotic drugs.
Taking drugs can spoil the life .Sometimes per pressure can lead to bad habits. Peer pressure
may have positive side but also have negative consequences for mental or physical health.

AIDS- Acquired Immuno deficiency syndrome

AIDS is caused by the Human Immunodeficiency Syndrome (HIV).

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It is a diseases f the immune system. It is transmitted by unprotected sex, through

contaminated syringes, blood transfusions and from infected pregnant mother to chil

अब इसकी पूरी समरी देता हूँ

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🔰 Introduction
🟢 Adolescence = The period of life जब बच्चा धीरे-धीरे adult बनता है।
🟢 यह 10–11 साल की उम्र से शुरू होकर 18–19 साल तक चलता है।
🟢 इसे Teenage भी कहते हैं क्योंकि इसमें 'teen' शब्द आता है (13–19)।
👉 This is the time when puberty (यौन परिपक्वता) शुरू होती है।
📌 Puberty: Physical and hormonal changes की process जिससे व्यक्ति प्रजनन योग्य
(capable of reproduction) बनता है।

📈 Changes During Adolescence (बदलाव किशोरावस्था में)

🔹 1. Growth Spurt (तेज़ी से लम्बाई बढ़ना)
 Bones of arms & legs तेजी से elongate करती हैं।
 अचानक height बढ़ती है।
🔹 2. Change in Body Shape
 Boys: Shoulders broad, chest wide
 Girls: Waist के नीचे का हिस्सा चौड़ा होता है
🔹 3. Change in Voice
 Boys: Voice deep, larynx बड़ा हो जाता है → Adam’s Apple बनता है
 Girls: Voice shrill हो जाती है
🔹 4. Sweat & Oil Glands Active
 ज्यादा पसीना, oily skin → acne/pimples (common but temporary)
🔹 5. Sex Organs Develop
 Boys: Testes sperm बनाना शुरू करते हैं
 Girls: Ovaries egg mature करना शुरू करती हैं
🔹 6. Mental & Emotional Growth
 Adolescents become self-aware, independent
 Intellect तेज़ होता है → Learning power highest
🔹 7. Secondary Sexual Characters
Boys में Girls में
Beard & Moustache Breast development
Deep voice Menstrual cycle starts
Body hair (underarms, chest) Body hair (underarms, pubic)

🧬 Role of Hormones (हार्मोन्स की भूमिका)

🧪 Hormones: Chemical messengers → glands से निकलकर body parts को signal देते हैं।
🔹 Secreted by: Endocrine glands (ductless)
🔹 Control center: Pituitary gland = Master gland
Hormone Role
Testosterone (Boys) sperm formation, male characters
Oestrogen (Girls) egg formation, female characters
Thyroxine Controls metamorphosis in frogs
Growth Hormone Boosts height & weight

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♀️Menstrual Cycle (मासिक धर्म चक्र)

In girls (Age 10–12 to 45–50 years)
🔁 हर 28–30 दिन में एक mature ovum रिलीज़ होता है।
📌 अगर fertilization नहीं होता:
 Ovum + uterus lining breakdown → bleeding through vagina
 इसे कहते हैं Menstruation (Periods)
Term Meaning
Menarche पहली बार periods शुरू होना
45–50 की उम्र में periods
Menopause
बंद होना

🧬 Sex Determination (लिंग निर्धारण)

🔹 Human body = 23 pairs of chromosomes
➡️Last pair = Sex Chromosomes
Female XX
Male XY
📌 Father का sperm decides gender:
 X sperm → X egg = Girl (XX) 👧
 Y sperm → X egg = Boy (XY) 👦
✅ Conclusion: Baby का gender father पर depend करता है, ना कि mother पर।

🍲 Nutritional & Reproductive Health

🟢 Teenagers = Rapid growth
🟢 जरूरत है: Balanced diet + Hygiene + Exercise
🥗 Balanced Diet =
Carbs + Proteins + Fats + Vitamins + Minerals (सही मात्रा में)
🧼 Hygiene:
 रोज़ नहाना, साफ कपड़े पहनना
 Girls: Special care during periods
🧘‍♂️Exercise:
 Yoga, cycling, outdoor games
 Depression, anxiety से भी बचाता है

🔁 Metamorphosis (कायांतरण)
📌 Definition: जब कोई organism (जैसे tadpole) drastic changes से adult बनता है।
Example Controlled by
Tadpole → Frog Thyroxine hormone (need iodine)
Caterpillar → Butterfly Insect hormones

🚫 Things to Avoid During Adolescence

❌ Smoking, drugs, alcohol
➡️Peer pressure से दूर रहो
➡️गलत संगत से बचो

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🦠 AIDS: Acquired Immuno Deficiency Syndrome

Point Detail
Virus HIV (Human Immunodeficiency Virus)
Effect Immune system कमजोर कर देता है
Spread Unprotected sex, infected needles, blood transfusion, infected mother to child

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Unit – 5 Reproduction in animal

1. Introduction
 Reproduction is the biological process by which new individual organisms are
produced.
 There are two basic types of reproductions namely asexual and sexual.
 Asexual reproduction is a process in which the organism reproduces on its own
without the help of another individual. There is only single parent.
 Sexual reproduction is a process in which two parents, a male and a female, are
needed to produce a new individual.

2. Reproduction in animals:
 In most animals, two individuals- a male and a female - are needed for reproduction,
therefore the reproduction is sexual.
 Each individual or parent produces a special sex cell known as gamete. In animals,
the gamete produced by the female is called the egg or ovum, and that produced by
the male is called the sperm.
 When the sperm and ovum fuse together, they form the zygote. This is the first cell of
the new organism. This process of fusion of a male gamete and a female gamete to
form a zygote is called fertilization.

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 The zygote undergoes cellular division and develops into an embryo. The embryo
eventually develops into a new individual.
 In animals such as frogs, fishes, birds, reptiles and humans, an individual carries only
one kind of gamete- either sperm (in the male) or the ovum (in the females).
However, some organisms produce both male and female gametes in the same
body. Such organisms are called hermaphrodites. Snail, slug, leech and earthworm
are examples of hermaphrodites.

Types of fertilization:
There are various methods by which fertilization takes place in the living world:

External fertilization:
 External fertilization is the process of fertilization in which fusion of the gametes takes
place outside the body of the organisms.
 In most aquatic animals, such as bony fish, the male and female release their sperms
and eggs into the surrounding water. The sperms swim to the eggs and fertilize them.
This fertilization takes place outside the parent's body.

Internal fertilization:
 Internal fertilization is the process of fertilization in which fusion of the gametes takes
place inside the body of the organisms.
 In organisms like reptiles, birds and mammals that usually live on land, sperms are
released directly into the body of the female since the sperms would be unable to
move on land. The males and females mate, and the sperms enter the female body
where they fertilize the eggs.

Reproduction in humans:
Fertilization in human is internal.,
Puberty:
The onset of sexual maturity occurs in boys at the age of 11-16 years, and in girls at the age of
10-15 years. This is known as puberty.

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The Male reproductive system:

 The male gametes or sperm are produced in a pair of testes. They are situated
outside the abdominal cavity in the scrotal sac.
 Each sperm is a single cell with the entire usual cell component. Each sperm has a
head, a middle piece and a tail.
 The sperm is carried by a pair of sperm ducts, called vas deferens, to the urethra
present in penis.
 Penis is the organ that transfers the sperms into the female reproductive tract.
 Sex glands pour a mixture of fluids into the sperm duct that keeps the sperms alive.
The sperm and the fluid together form the semen.

1. A pair of testes (Produce sperm and male hormone i.e. testosterone)

2. Two sperm ducts
3. Scrotum (Protects testes and maintains a temperature lower than body temperature)
4. Epididymis (Stores sperms and helps in the passage of sperms)
5. Vas deference (tube like structure that emerges from the lower part of epididymis and opens to
the ejaculatory duct)
6. Penis (muscular organ that discharge the sperms when stimulated)
7. Male gametes called sperms (produced by testes)
The sperms are small sized and contain following parts:

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1. A head (contains the nucleus containing chromatin fibre. It contains enzymes used for
penetrating the female egg).
2. A middle segment (provide the energy for the flagellar movement of sperm)
3. A tail (consists of only the 9+2 structure of the axoneme that contains many proteins and protein
complexes required for the proper functioning of sperms

Female reproductive system:

 The female reproductive organs are a pair of ovaries, the oviduct (fallopian tubes)
and the uterus.
 These are located in the lower part of the abdomen.
 The ovaries produce the egg or ovum when a female reaches puberty.
Female reproductive organ
The female reproductive system includes the following parts:

1. A pair of ovaries (Produce female sex cell i.e. ovum and female hormone i.e. estrogen and
progesterone)
2. Fallopian tubes (Receives ovum from ovary)
3. Uterus (development of baby takes place)
4. Female gametes called ova (produced by ovary)
Fertilization:
 Male gametes are introduced into the female reproductive tract by the penis. Both the
gametes meet in the oviduct. The fusion between a male gamete and a female
gamete in the oviduct result in the formation of a fertilized egg or zygote.
 Fertilization and development of the zygote to form a new individual takes place
inside the body of the female.

Development of the fetus:

 After fertilization, the zygote passes into the uterus, or womb. It divides again and
again to form the embryo. The embryo becomes embedded in the lining of the wall of
the uterus. This is called implantation.
 At two months, the embryo starts resembling the human form is called the foetus. It
takes nine months for the embryo to grow and develop into a fully-formed baby. This
period is called gestation period.
 The foetus is attached to the uterus by a special structure called the placenta. The
placenta is responsible for providing oxygen and nutrients and removing waste
substances.
Process involved in Sexual reproduction

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 Every month eggs are released from the ovaries in a female reproductive
system. This phenomenon is called ovulation.
 The first step is the fusion of a sperm from male and an ovum from female.
This is called fertilization.

Fig. Fertilization

 During the fertilization the nucleus of a sperm and ovum fuse and forms a
single nucleus that develops into a fertilized egg or zygote.

Fig. Zygote formation and development of embryo from zygote

 The zygote further undergoes repeated divisions and gives rise to ball of
cells that form groups and develops into different tissues and organs of
body. This structure is called embryo.

Fig. Repeated division of zygote to form embryo

It gets later gets embedded in the walls of uterus.
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Fig. Developing Embryo

It develops the different body parts like hands, legs, eyes, ears, nose, etc. this
phase of embryo when it has developed all its body parts is called foetus.

Fig. Foetus

Fig. A pregnant Woman

After complete development of embryo a new individual is born

In Vitro fertilization (IVF):

 It is a method in which ovum collected from a female's body is allowed to fuse with
sperm collected from a male's body in an external medium or outside the body of the
female.
 The zygote so developed is allowed to grow in vitro (i.e.in glass) for about a week
and then implanted in the female's uterus where it further develops as a normal
embryo.
 A baby born of this technique is often called a 'test tube' baby.

Viviparous and oviparous animals:

 Animals that give birth to young ones are known as viviparous animals.
 In these animals, the development of the embryo takes place inside the body of the
mother, human, tiger, goats and cats are some examples of viviparous animals.
 Animals that lay eggs are known as oviparous animals. In these animals, the
development of embryo takes place in the egg after it is laid. Birds, lizards, crocodiles
are some examples of oviparous animals.

Metamorphosis:

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A frog passes through three stages during its development from an egg to an adult
frog:

 Butterflies and moths pass through four stages before winged adult is born:

 The transformation of larva into an adult through drastic changes is called

metamorphosis.

Asexual reproduction:
Asexual reproduction involves the production of new organisms by just one parent. Some of
the asexual reproductions are:
Binary fission:
The process by which an organism reproduces by dividing into two cells from a single cell is
called binary fission. Binary fission is seen in single-celled organisms, such as Amoeba and
Paramecium.
Budding:
In budding, a new organism grows in the form of a bulb-like projection called a bud from the
parent organism. It grows and may eventually break away from the parent. Yeast and Hydra
reproduce by budding.
Reproduction in Hydra

 Reproduction in hydra starts by the development of bulges called buds.

 The buds are the small outgrowths from a parent hydra that develops into
a new hydra.
 As the new individual develops from buds the process of reproduction in
hydra is called budding.

Reproduction in Amoeba

 Amoeba is a single celled organims that reproduces new individual of its

type by dividing its nucleus into two nuclei.
 after division of the nucleus the body of amoeba divides into two parts
with each individual part receiving a nucleus.
 The two separate bodies of amoeba develops into new individuals.
 This method of reproducing new individual by dividing into two individual
is called binary fission.

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competitive exam for class 8th Shastri Nagar Sultanpur 9455857477

अब मै इसका summary Hinglish me देता हूँ आप ratna मत,

कुछ न समझ आये तो मुझसे पूछ लेना लेकिन ratna मत
🌱 1. Reproduction क्या होता है?
👉 Reproduction एक process है जिससे living things (जैसे इंसान, जानवर, पौधे) अपने जैसे नए
बच्चे बनाते हैं।
दो प्रकार के reproduction होते हैं:
1. Asexual reproduction – एक ही parent होता है, दूसरा कोई नहीं।
जैसे: Amoeba, Hydra
2. Sexual reproduction – दो parent होते हैं: एक male और एक female।
जैसे: इंसान, कुत्ता, बिल्ली

👫 2. Sexual Reproduction कैसे होता है?

 Male बनाता है – sperm (स्पर्म)
 Female बनाती है – egg या ovum (अंडाणु)
 जब sperm और egg मिलते हैं → Zygote बनता है
 Zygote → divide होकर embryo बनता है → फिर baby
इसे Fertilization (निषेचन) कहते हैं।

🐸 3. Fertilization के प्रकार
प्रकार कहाँ होता है उदाहरण
female के शरीर के इंसान,
Internal fertilization
अंदर बिल्ली
शरीर के बाहर (पानी मछली,
External fertilization
में) मेंढक

👦 4. Male Reproductive System

हिस्सा काम
Testes sperm बनाते हैं
Scrotum testes को ठंडा रखते हैं
Penis sperm female के शरीर में पहुंचाता है
बहुत छोटा cell होता है जिसमें head, middle और tail
Sperm
होता है

👧 5. Female Reproductive System

54 By Adarsh Kumar
Easy & concise notes for Pinaki Vigyan Mandir
competitive exam for class 8th Shastri Nagar Sultanpur 9455857477

हिस्सा काम
Ovary egg बनाती है
यहीं sperm और egg मिलते
Fallopian tube
हैं
Uterus baby यहीं grow करता है

👶 6. Human Baby कैसे बनता है?

1. लड़की की ovary egg छोड़ती है (ovulation)
2. लड़के के sperm से egg मिलता है → Zygote
3. Zygote → embryo बनता है
4. Embryo uterus में चिपकता है (implantation)
5. धीरे-धीरे baby बनता है (9 months लगते हैं)
Baby और मां के बीच placenta होता है, जो oxygen और खाना देता है।

🧪 7. IVF (Test Tube Baby)

जब fertilization female के शरीर के बाहर होता है और embryo को बाद में uterus में डाला
जाता है – उसे कहते हैं IVF। ऐसा बच्चा कहलाता है test tube baby।

🥚 8. Viviparous vs Oviparous Animals

प्रकार क्या होता है उदाहरण
मां के शरीर में baby इंसान,
Viviparous
बनता है बिल्ली
मुर्गी,
Oviparous अंडे देती हैं
मछली

🔁 9. Metamorphosis (कायांतरण)
जब बच्चे का रूप adult से बहुत अलग होता है और धीरे-धीरे बदलता है – उसे
metamorphosis कहते हैं।
उदाहरण:
 Tadpole → Frog
 Caterpillar → Butterfly
🌿 10. Asexual Reproduction (एक माता-पिता से)
1. Binary fission – एक cell दो में बंट जाता है
👉 Example: Amoeba
2. Budding – एक छोटी सी गाठ (bud) से नया बच्चा बनता है
👉 Example: Hydra, Yeast
🧠 याद रखने लायक बातें (Revision Box)
✅ Sperm + Egg → Zygote
✅ Fertilization inside body = Internal
✅ Amoeba = Binary fission
✅ Hydra = Budding

55 By Adarsh Kumar
Easy & concise notes for Pinaki Vigyan Mandir
competitive exam for class 8th Shastri Nagar Sultanpur 9455857477

✅ IVF = Outside fertilization (Test tube baby)

✅ Frog = Metamorphosis
कुछ न समझ आये तो पूछ लेना 9455857477

56 By Adarsh Kumar