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NAME- SWARNADEEP
MONDAL
CLASS- XI,
ROLL- 34,
SEC- (A),
YEAR- 2024

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ACKNOWLEDGEMENT
In the accomplishment of this project successfully, many people have
best owned upon me their blessings and the heart pledged support,
this time I am utilizing to thank all the people who have been
concerned with this project.

Primarily I would thank god for being able to complete this project with
success. Then I would like to thank my principal Mrs. Ranjita Paul and
biology teacher Mrs. Sucharita Samadder and Mrs. Anindita Dutta
whose valuable guidance has been the ones that helped me patch this
project and make it full proof success. His suggestions and his
instructions have served as the major contributor towards the
completion of the project.

Then I would like to thank my parents and friends who have helped me
with their valuable suggestions and guidance has been very helpful in
various phases of the completion of the project.

Last but not the least I would like to thank my classmates who have
helped me a lot.

Signature of Student Signature of Teacher

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1. STUDY OF THE DEVELOPMENTAL

STAGES OF COCKROACH

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Index

Page 1- Cover Page

Page 2- Acknowledgement
Page 3- Topic
Page 4- Index
Page (5-16)- Description
Page 17- Conclusion
Page 18- Bibliography

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Introduction:
Cockroaches are considered to be insects that pose a threat, and we
have all dealt with cockroach infestations in our homes. Roaches or
cockroaches belong to the superorder Dictyoptera’s suborder Blattodea.
The Dictyoptera class of insects includes cockroaches and mantids,
which are distinguished by their flat, oval-shaped bodies, leathery
wings, and lengthy antennae. Understanding their past is crucial for
having a better understanding of these insects. One of the oldest
insects, cockroaches has 320 million-year-old fossils.

Despite having lived on earth for a very long time, they are disliked
everywhere they go. In addition to damaging household food products
and leaving behind a foul smell, cockroaches are also thought to be
disease carriers. Let’s now examine the cockroach life cycle to gain
better knowledge.

Physical description:
As in other insects, the body of a cockroach consists of a
head, a thorax, and an abdomen. The head has long
threadlike antennae and is bent downward; the mouthparts
point backward instead of forward or downward, as is the
case in most other insects. The compound eyes are well-
developed in most species but are absent or reduced in cave-
dwelling species. The body is flattened and oval in shape and
usually features a shining black or brown leathery
integument, though some species are green or feature
distinctive markings. Male cockroaches usually have two
pairs of wings, whereas females, in some species, are
wingless or have vestigial wings. The structure and large
size (certain species have a wingspread of more than 12 cm
[4.7 inches]) of cockroaches have made them objects of
interest in the biology laboratory.

All cockroach species, with the exception of those in the

small genus Nocticola, are thought to host Blattabacterium,

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a mutualistic bacterium. The endosymbiotic bacterium lives

within the insects’ fat cells and is thought to help
regulate purine metabolism and allow the insects to survive
on nitrogen-poor diets.

Natural history:
Many cockroaches prefer warm, humid, dark environments,
and many are active at night. The cockroaches of the family
Blaberidae are viviparous (bear living young), but the
females of most other species produce eggs in well-formed
egg cases (called oothecae). These are sometimes held
protruding from the mother’s body until hatching time is
near, or they may be glued in protected areas. Usually, each
ootheca contains from a few to more than 30 eggs arranged
in two rows. Along one edge of the ootheca is a seam that
bears a keel, or ridge; the shape of the ridge varies in
species that carry the ootheca externally. Minute openings
from the base of the keel to the interior of the ootheca are
known to be a ventilating device in some species. After the
female deposits an egg case, soft white nymphs emerge. As
their exoskeleton hardens, it develops its coloration.

Pest species often damage more material than

they consume and often emit a disagreeable odor. The diet
of such roaches, which includes
both plant and animal products, ranges from food, paper,
clothing, and books to dead insects, especially bedbugs. Able
to spread bacteria and viruses from their legs to human food
and household surfaces, pest species are known to
spread dysentery (caused by Entamoeba histolytica), E.
coli,salmonella, and other types of food
poisoning. Insecticides are used in roach control, though

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those sprayed outdoors kill many nontarget insects and

other invertebrates and have been linked to global insect
declines.

Although cockroaches are generally disliked by humans, the

vast majority of species are not pests; rather, they are
important members of the ecosystems they inhabit. Like
other insects, they play a key role in food webs and nutrient
cycling. Ensign wasps, for example, are parasitoid wasps
that prey on cockroach eggs as food for their larvae.
Many frogs, lizards, birds, and small mammals also rely on
cockroaches in their diet.

Life Cycle of Cockroach:

The life cycle of cockroach involves three main stages: egg, nymph,
and adult. This type of development is known as incomplete

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metamorphosis. Each stage of life cycle of cockroach is explained

below:

1. Egg Stage:

 Ootheca Formation: Female cockroaches produce egg

cases called oothecae. An ootheca can contain multiple eggs,
ranging from 10 to 50, depending on the species.
 Ootheca Deposition: The female carries the ootheca for a
period before depositing it in a secure, warm, and humid
location. Some species may drop the ootheca shortly after
formation, while others may carry it until the eggs are nearly
ready to hatch.
 Incubation: The eggs inside the ootheca undergo incubation,
which can last from a few weeks to several months. The time
taken for the eggs to hatch can be affected by factors like
temperature, with warmer conditions generally speeding up
development.

2. Nymph Stage:

The nymph stage can last several months to over a year, depending
on the species and environmental conditions. For example, German
cockroach nymphs develop into adults in about 6 to 12 weeks, while
American cockroach nymphs may take 6 months to over a year.

 Hatching: Nymphs emerge from the ootheca. They resemble

small, wingless adults and are pale or white initially, darkening
as their exoskeleton hardens.

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 Molting Process: Nymphs go through a series of molts (5 to

13 instars) as they grow. During each molt, the nymph sheds its
old exoskeleton and forms a new, larger one.
 Growth and Development: With each molt, the nymphs
grow larger, gradually developing more adult-like features, such
as wings and reproductive organs. The number of molts and
the time between them can vary depending on the species and
environmental conditions.

3. Adult Stage:

 Final Molt: The last molt transforms the nymph into an adult
cockroach. Adult cockroaches are fully developed, with wings
(in most species) and functional reproductive organs.

 Mating Behavior: Adult cockroaches engage in mating

behaviour, where males use pheromones to attract females.
After mating, females can produce multiple oothecae over their
lifetime.
 Lifespan: The adult lifespan of a cockroach can vary widely.
For instance, the German cockroach lives for about 100 to 200
days as an adult, while the American cockroach can live up to
400 days or more under ideal conditions.
 Reproduction: Adult cockroaches reproduce throughout their
lifespan. Females can produce multiple oothecae during their
lifetime, with each ootheca containing numerous eggs.

Key Points of Life Cycle of Cockroach:

 Incomplete Metamorphosis: Cockroaches undergo

incomplete metamorphosis, meaning they do not have a pupal

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stage. Instead, they develop through a series of molts from

nymph to adult.
 Adaptability: Cockroaches are highly adaptable and can
thrive in a variety of environments, from tropical regions to
human dwellings.
 Survival Strategies: Their life cycle stages are adapted to
ensure survival, with eggs protected in oothecae, nymphs
capable of rapid growth and development, and adults skilled in
reproduction and finding food sources.

Major genera and species:

The taxonomy of the order Blattodea and of cockroaches
in particular has been contentious. The number of
families varies depending on the source, usually ranging
from five to seven.

Family Blattidae:
The family Blattidae contains several common household
cockroaches. The American
cockroach (species Periplaneta americana), a native of
Africa and the Middle East, is 30 to 50 mm (1.2−2
inches) long, is reddish brown, and lives outdoors or in
dark heated indoor areas (e.g., basements and furnace
rooms). During adult life, a
period of about 1.5 years, the
female deposits 50 or more
oothecae, each containing
about 16 eggs, which hatch
after 45 days. Nymphal life
lasts from 11 to 14 months.
The American cockroach has well-developed wings.
However, most species of Blattidae are not good fliers.

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Also in the family is the Oriental cockroach, or black

cockroach (Blatta orientalis), which is considered to be
one of the most notorious household pests. It is oval,
shiny black or dark brown, and 25 to 30 mm (1 to 1.2
inches) long, with a life cycle similar to that of the
American cockroach. The male has short fully developed
wings, and the female has vestigial wings. This
cockroach has been distributed by vehicles of commerce
from Eurasia to all the world’s temperate regions.

Family Ectobiidae:
Many other familiar cockroach species are members of
the family Ectobiidae (formerly Blattellidae). The German
Cockroach (Blattella
germanica), a common
household pest, is light
brown with two dark
stripes on the prothoracic
region. The female
produces an ootheca 3
days after mating and
carries it for about 20
days. Three or more
generations may occur
yearly. Because it is small
(about 12 mm [less than 0.5 inch] long), this cockroach is
often carried into homes in grocery bags and boxes. It
has spread throughout the world, thanks to human
transport, including long-distance transport by ship.

The brown-banded cockroach (Supella

longipalpa) resembles the German cockroach but is
slightly smaller. The male has fully developed wings and
is lighter in color than the female, whose wings are short

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and nonfunctional. Both sexes have two light-colored

bands across the back. The adult lifespan is about 200
days, and there may be two generations annually. Eggs
may be deposited in clothes, wood molding, or cracks in
the floor. With the advent of heated buildings, this
cockroach became established in cooler climates.

The Pennsylvania wood cockroach (Parcoblatta

pennsylvanica) is found under logs and stones in
northern latitudes. The male and female are so different
in appearance that they were once considered separate
species. The male, 15 to 25 mm (0.6 to 1 inch) long, has
wings that extend past the abdomen. The female is
smaller and has much shorter wings. The species is not
considered to be a pest.

Family Blaberidae:
Known for its giant cockroaches, Blaberidae is a large
family of large cockroaches. The
most famous of these is
the Madagascar hissing
cockroach (Gromphadorhina
portentosa), one of the most
sizeable of all cockroach species.
Reaching 5 to 7.5 cm (2 to 3
inches) in length, the Madagascar
hissing cockroach is sometimes kept as a pet.

Other notable members of the family include the green

banana cockroach (Panchlora nivea), death’s head
cockroach (Blaberus craniifer), and emerald cockroach
(Corydidarum magnifica). The giant burrowing
cockroach, or rhinocerous cockroach (Macropanesthia

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rhinoceros), of Australia is one of the heaviest cockroach

species and weighs about 30 grams (1 ounce).

Family Corydiidae:
There are some 40 genera of sand
cockroaches of the family Corydiidae,
including Polyphaga, Arenivaga, Ther
ea, and the relatively
colorful Eucorydia. The question-
mark cockroach (Therea
olegrandjeani)
has conspicuous black-and-white markings and is
sometimes kept as a pet. A related species, known as the
domino cockroach (T. petiveriana), is black with seven
white spots on its abdomen.

The desert cockroach (Arenivaga investigata)

inhabits Sand dunes in the Colorado Desert in
southern California.

Family Cryptocercidae:
The family Cryptocercidae, which
consists of a single
genus, Cryptocercus, is the
cockroach group most closely
related to termites. The brown-
hooded cockroach (C. punctulatus)
digests wood with the aid of certain protozoans in
its digestive tract.

Family Nocticolidae:
About 25 species of largely cave-
adapted cockroaches constitute the
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family Nocticolidae; some sources place this group

within Corydiidae. They are found in Africa, Asia, and
Australia. Gerlach’s cockroach (Nocticola gerlachi) is
an endangered species endemic to the Seychelles.

Life Span of Cockroach:

The lifespan of an American cockroach (Periplaneta americana)
depends on various factors such as environment, diet, and
overall conditions. In favorable conditions, cockroaches
experience rapid growth and longer lifespans, while unfavorable
conditions can lead to early death. An American cockroach lives
for about a year, during which it reproduces, lays eggs, and
contributes to the population growth. The following factors
significantly influence their lifespan:
 Breed: Different cockroach species have varying lifespans
and adapt to different environmental conditions. For
example, American cockroaches generally have a lifespan
of about one year, whereas German cockroaches might live
for a shorter duration.
 Diet: Access to a sufficient and balanced diet is crucial for
cockroach survival. Cockroaches are omnivores and can
eat a wide range of organic materials. A consistent food
source supports their growth and reproduction and extend
their lifespan.
 Environment: Environmental factors such as humidity and
temperature play a vital role in the development and
survival of cockroaches. American cockroaches thrive in
warm and humid conditions. Optimal environmental
conditions promote faster development and a longer
lifespan, while extreme conditions can reduce their survival
rates.
Habitat and Food Habits of Cockroach:

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Cockroaches are commonly found in human dwellings,

particularly in kitchens, bathrooms, basements, and other areas
where food and moisture are available.

 They inhabit restaurants, supermarkets, hospitals, and

offices, especially in places where food is stored, prepared,
or consumed.
 Cockroaches thrive in dark, moist environments, making
sewers and drains ideal habitats .
 In tropical and subtropical regions, cockroaches can be
found outdoors under logs, leaf litter, and in gardens.
 Cockroaches seek shelter in narrow spaces where they are
protected from predators and can find stable environmental
conditions.

Food Habits of Cockroaches:

Cockroaches are primarily nocturnal and feed at night. They

often forage for food when the environment is quiet and dark.
They are scavengers that consume a wide range of organic
materials, including decaying matter, food scraps, and waste.
 They feed on any type of human food, especially starchy,
sugary, and fatty foods. This includes crumbs, spilled
liquids, and food residues.
 Cockroaches can chew on paper products, book bindings,
and fabrics, especially those with food stains.
 They are attracted to the glue found in book bindings,
stamps, and wallpaper.
 Cockroaches need access to water to survive. They can
live for about a month without food but only about a week
without water.
 They may feed in groups, which can help locate food
sources more efficiently and increase survival rates.

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Economical Importance of Cockroach:

The economic importance of cockroach are:
 Pest Control Costs: Significant financial resources are
spent on pest control services and products to manage and
eliminate cockroach infestations in homes, restaurants, and
other establishments.
 Food Industry Impact: Cockroach infestations can lead to
food contamination and spoilage, resulting in economic
losses for food manufacturers, processors, and retailers.
 Health Care Costs: Medical expenses related to treating
allergic reactions, asthma, and other health issues caused
by cockroach exposure can be substantial.
 Property Damage: Cockroaches can cause damage to
property by chewing on materials such as paper, fabric,
and leather, leading to economic losses for homeowners
and businesses.
 Agricultural Impact: In agricultural settings, cockroaches
can damage crops and stored produce, contributing to
economic losses for farmers and distributors………

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Conclusion
Cockroaches usually prefer a warm, dark-dingy and
humid climate to survive. Cockroaches and termites
are similar but termites feed on wood, unlike
omnivorous cockroaches. Cockroaches undergo
incomplete metamorphosis, progressing through
egg, nymph, and adult stages. Eggs are laid in
protective cases called oothecae, which hatch into
nymphs resembling miniature adults. Nymphs
undergo several molts, growing larger with each
molt, before reaching adulthood. Adults reproduce,
with females producing oothecae containing eggs.
Environmental factors and species variations
influence the duration and success of each stage in
the cockroach life cycle.

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Bibliography
 www.britannica.com
 www.wikipedia.org
 https://byjus.com
 www.geeksforgeeks.org
 www.scribd.com
 https://openai.com/chatgpt/
 www.vedantu.com

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