Biology notes: finals

Contents
Hormones: .............................................................................................................................................. 2
Endocrine disorders: ............................................................................................................................... 3
Theories of Evolution: ............................................................................................................................. 4
Lamarckism: ........................................................................................................................................ 4
Darwinism: .......................................................................................................................................... 5
Differences: ............................................................................................................................................. 7
Differences Between Chemical and Mechanical Digestion ................................................................. 7
Differences Between Peristalsis and Antiperistalsis............................................................................ 7
Differences Between Spermatogenesis and Oogenesis ...................................................................... 8
Differences Between DNA and Chromosomes.................................................................................... 8
Differences Between Larynx and Pharynx........................................................................................... 9
Differences Between Growth and Development ................................................................................ 9
Differences Between RBCs and WBCs ............................................................................................... 10
Differences Between Arteries and Veins ........................................................................................... 10
Differences Between Egestion and Excretion ................................................................................... 11
Differences Between Homozygous and Heterozygous Genes .......................................................... 11
Differences Between Breathing and Respiration .............................................................................. 11
Differences Between Aerobic and Anaerobic Respiration ................................................................ 12
Definitions ............................................................................................................................................. 12
Disorders: .............................................................................................................................................. 13
1. Chronic Bronchitis: ........................................................................................................................ 13
2. Chronic Obstructive Pulmonary Disease (COPD): ......................................................................... 14
3. Emphysema: .................................................................................................................................. 14
4. Lung Cancer:.................................................................................................................................. 14
5. Atherosclerosis: ............................................................................................................................. 14
6. Varicose Veins: .............................................................................................................................. 15
 Hormones:
Hormone Gland Target Organ Function

Pancreas Liver, muscles, Regulates blood glucose levels by promoting the

Insulin
(Beta cells) fat cells uptake of glucose from the blood into cells.

Pancreas Stimulates the liver to release glucose into the

Glucagon Liver
(Alpha cells) bloodstream, increasing blood sugar levels.

Various body
Thyroid hormones (T3 and T4) Thyroid gland Regulates metabolism, growth, and development.
cells

Increases blood calcium levels by stimulating

Parathyroid Bone, kidneys,
Parathyroid hormone (PTH) calcium release from bones, reabsorption in
glands intestines
kidneys, and absorption in the intestines.

Reproductive Regulates female reproductive system, promotes

Estrogen Ovaries organs, bones, development of female secondary sexual
skin characteristics, maintains bone density.

Prepares the uterus for pregnancy and regulates the

Progesterone Ovaries Uterus
menstrual cycle.

Reproductive Regulates male reproductive system, promotes

Testosterone Testes organs, muscles, muscle and bone growth, and development of male
bones secondary sexual characteristics.

Pituitary
Stimulates milk production in females after
Prolactin gland Mammary glands
childbirth.
(Anterior)

Pituitary Various body

Stimulates growth, cell reproduction, and
Growth hormone (GH) gland tissues, muscles,
regeneration.
(Anterior) bones

Pituitary
Stimulates the thyroid gland to produce thyroid
Thyroid-stimulating hormone (TSH) gland Thyroid gland
hormones (T3 and T4).
(Anterior)

Pituitary Ovaries In females, triggers ovulation and stimulates the

Luteinizing hormone (LH) gland (Females), testes production of estrogen and progesterone. In males,
(Anterior) (Males) stimulates testosterone production.

Pituitary Ovaries
In females, stimulates the development of ovarian
Follicle-stimulating hormone (FSH) gland (Females), testes
follicles. In males, stimulates sperm production.
(Anterior) (Males)

Pituitary
Regulates water balance by promoting water
Antidiuretic hormone (ADH) gland Kidneys
reabsorption in the kidneys, reducing urine output.
(Posterior)
Hormone Gland Target Organ Function

Pituitary
Uterus, Stimulates uterine contractions during childbirth
Oxytocin gland
mammary glands and milk ejection during breastfeeding.
(Posterior)

Melatonin Pineal gland Brain Regulates sleep-wake cycle (circadian rhythm).

Pituitary
Adrenal glands Stimulates the adrenal glands to produce cortisol
Adrenocorticotropic hormone (ACTH) gland
(Cortex) and other corticosteroids.
(Anterior)

Adrenal
Various body Regulate metabolism, immune response, and stress
Corticosteroids glands
tissues response; include cortisol, aldosterone, and others.
(Cortex)

Adrenal Prepare the body for fight-or-flight responses by

Catecholamines (Adrenaline & Heart, muscles,
glands increasing heart rate, blood pressure, and energy
Norepinephrine) blood vessels
(Medulla) availability.

Endocrine disorders:
Condition Cause Key Characteristics/Effects

- Enlargement of hands, feet, and facial features (e.g.,

Overproduction of growth
enlarged jaw, nose, and tongue)
Acromegaly hormone (GH), usually caused by
- Joint pain, thickened skin
a pituitary tumour (adenoma).
- Increased risk of cardiovascular disease and diabetes

Insufficient production of
- Excessive thirst (polydipsia)
antidiuretic hormone (ADH) or
Diabetes Insipidus - Frequent urination (polyuria)
resistance to it (due to kidney
- Dilute urine, leading to dehydration if not managed
dysfunction).

Type 1: Insulin deficiency due to

- Elevated blood glucose levels (hyperglycaemia)
autoimmune destruction of
- Symptoms: increased thirst, frequent urination,
Diabetes Mellitus pancreatic beta cells.
weight loss (Type 1), fatigue, blurred vision, and slow
Type 2: Insulin resistance and
healing of wounds (Type 2)
eventual beta cell failure.

Most commonly caused by - Short stature

growth hormone deficiency or - Potential skeletal deformities (in the case of genetic
Dwarfism
genetic conditions such as forms)
achondroplasia. - Normal intelligence in most cases

Overproduction of growth - Excessive growth of long bones

Gigantism hormone (GH) in childhood - Abnormal enlargement of the hands, feet, and facial
before the closure of epiphyseal features
Condition Cause Key Characteristics/Effects

growth plates, usually due to a - Delayed puberty and potential cardiovascular

pituitary tumour. complications

- Hyperthyroidism symptoms: weight loss, rapid

Autoimmune disorder that causes
heartbeat, heat intolerance, fatigue
Graves' Disease hyperthyroidism (overproduction
- Eye symptoms: bulging eyes (exophthalmos)
of thyroid hormones).
- Goitre (enlarged thyroid)

Overproduction of parathyroid
- High blood calcium levels (hypercalcemia)
hormone (PTH), usually due to a
Hyperparathyroidism - Weak bones (osteoporosis), kidney stones
parathyroid adenoma or
- Fatigue, muscle weakness, constipation
hyperplasia.

Insufficient production of
parathyroid hormone (PTH), often - Low blood calcium levels (hypocalcaemia)
Hypoparathyroidism due to damage to the parathyroid - Muscle cramps, spasms, and numbness
glands during surgery or - Seizures in severe cases
autoimmune conditions.

Low blood glucose levels, usually - Symptoms: shakiness, sweating, confusion,

Hypoglycaemia due to insulin overdose, certain dizziness, irritability, weakness, and in severe cases,
medications, or prolonged fasting. seizures or loss of consciousness

Excessive androgen (male

- Development of male secondary sexual
hormone) production in females,
characteristics in females, such as deepening voice,
Virilism often due to ovarian or adrenal
increased body hair (hirsutism), and enlarged clitoris
tumours, or polycystic ovary
- Disrupted menstrual cycle
syndrome (PCOS).

Theories of Evolution:
Lamarckism:
1. Lamarck's Theory: Proposed by Jean-Baptiste Lamarck, it suggested species evolve
over time due to environmental changes and internal needs.
2. Environmental Influence: Lamarck believed organisms adapt to new needs that arise
from environmental changes.
3. Use & Disuse: Traits or organs that are frequently used become stronger, while
unused organs atrophy.
4. Inheritance of Acquired Characteristics: Traits acquired during an organism's
lifetime are passed down to offspring.
5. Speciation: Over time, new species could arise from existing ones due to
accumulated changes.
6. New Needs: Organisms develop new traits to meet evolving environmental demands.
 7. Example of Giraffes: Lamarck suggested giraffes developed long necks because
ancestors stretched their necks to reach tall trees.
8. Inheritance Mechanism: Lamarck proposed that acquired traits (e.g., longer necks)
were inherited by offspring.
9. Criticism 1 – Lack of Evidence: No experimental proof that acquired traits are
passed to offspring.
10. Criticism 2 – Contradicts Genetics: Lamarckism conflicts with Mendelian genetics,
which shows traits are inherited via genes.
11. Criticism 3 – Lack of Mechanism: Lamarck couldn't explain how acquired traits
were inherited biologically.
12. Criticism 4 – Acquired Traits Aren’t Inherited: Modern genetics disproved the
inheritance of traits acquired through use or disuse.
13. Lamarck’s Mistakes – Inheritance of Acquired Traits: Belief that traits acquired
during life could be passed to offspring was incorrect.
14. Lamarck’s Mistakes – Overemphasis on Environment: Focused too much on the
environment, neglecting the role of genetic variation and natural selection.
15. Lamarck’s Mistakes – No Genetic Knowledge: His theory lacked the understanding
of DNA and gene-based inheritance.
16. Significance 1 – Early Contribution: Lamarck was one of the first to propose
evolution as a process of change over time.
17. Significance 2 – Adaptation: Emphasized the role of adaptation to the environment,
influencing later evolutionary theories.
18. Significance 3 – Organism-Environment Interaction: Highlighted how organisms
interact with their environment, foreshadowing ecological studies.
19. Significance 4 – Stimulating Research: Lamarck’s ideas spurred further research,
leading to Darwin's natural selection theory and the modern synthesis of evolution.
20. Legacy: Although flawed, Lamarck’s theory helped lay the groundwork for future
evolutionary theories.

Darwinism:
1. Darwinism: A theory of evolution proposed by Charles Darwin, explaining how
species evolve through natural selection.
2. H.M.S. Beagle Voyage (1831-1836): Darwin’s five-year voyage around the world
aboard the Beagle significantly influenced his evolutionary ideas.
3. Observations on the Beagle: Darwin observed distinct species across different
islands, especially in the Galápagos, which led to his insights on adaptation and
evolution.
4. Fossils: Darwin found fossils of extinct species that resembled living species,
suggesting species could change over time.
5. Endemic Species: Darwin observed unique species on isolated islands, helping him
understand how adaptation to specific environments works.
6. Charles Darwin: Born in 1809, Darwin was an English naturalist who developed the
theory of evolution by natural selection.
7. "On the Origin of Species" (1859): Darwin’s landmark book that laid out his theory
of evolution, including the mechanism of natural selection.
8. Natural Selection: Darwin proposed that individuals with advantageous traits survive
and reproduce, passing those traits to the next generation.
9. Overproduction: Organisms produce more offspring than the environment can
support, leading to competition for resources.
10. Competition: Since resources are limited, individuals compete for food, mates, and
shelter, affecting their survival and reproduction.
11. Genetic Variation: Within populations, there is variation in traits, which can affect
the survival and reproductive success of individuals.
12. Adaptation: Traits that improve survival or reproduction in a given environment
become more common in the population over generations.
13. Natural Selection in Action: Organisms with beneficial traits are more likely to
survive and reproduce, leading to the accumulation of those traits in future
generations.
14. "Survival of the Fittest": The phrase emphasizes that the most well-adapted
individuals are the ones most likely to survive and reproduce.
15. Speciation: Over time, accumulated changes lead to the formation of new species,
particularly when populations become isolated and cannot interbreed.
16. Geographic Isolation: When populations are geographically separated, they evolve
differently, leading to the formation of distinct species.
17. Reproductive Isolation: As differences accumulate, isolated populations may no
longer interbreed, resulting in the emergence of new species.
18. Significance 1 – Unifying Biology: Darwin's theory unified the study of biology by
explaining the diversity of life through evolution.
19. Significance 2 – Modern Evolutionary Theory: Darwinism laid the foundation for
the Modern Synthesis, which integrates genetics into the theory of evolution.
20. Significance 3 – Genetic Impact: Darwin’s work inspired research into genetics,
leading to a deeper understanding of inheritance and variation.
21. Significance 4 – Natural Selection: Darwin highlighted natural selection as the key
mechanism for evolutionary change, influencing countless studies in biology.
22. Significance 5 – Common Ancestry: Darwin’s theory provided evidence for the idea
that all living organisms share a common ancestry.
23. Criticism 1 – Lack of Genetic Mechanism: At the time, Darwin could not explain
how traits were inherited, as genetics were not understood yet.
 24. Criticism 2 – Fossil Gaps: Critics argued that the fossil record was incomplete, with
missing transitional forms between species.
25. Criticism 3 – Rate of Evolution: Some felt that gradual evolution couldn’t account
for the rapid appearance of new species, leading to debates on the pace of evolution.

Differences:
Differences Between Chemical and Mechanical Digestion
1. Chemical Digestion:
o Definition: The process by which enzymes break down food into simpler
molecules (e.g., proteins into amino acids, carbohydrates into sugars).
o Location: Occurs mainly in the stomach and small intestine.
o Involves: Enzymes (e.g., amylase, pepsin, lipase) and digestive juices.
o Purpose: Breaks down complex food molecules into absorbable nutrients.
o Example: The breakdown of starch into glucose by amylase.
2. Mechanical Digestion:
o Definition: The physical breakdown of food into smaller pieces without
changing its chemical structure.
o Location: Occurs in the mouth (chewing) and stomach (churning).
o Involves: Teeth, tongue, and stomach muscles.
o Purpose: Increases the surface area of food to enhance the efficiency of
chemical digestion.
o Example: Chewing of food to break it down into smaller pieces.

Differences Between Peristalsis and Antiperistalsis

1. Peristalsis:
o Definition: The rhythmic contraction and relaxation of muscles in the
digestive tract that moves food along the digestive system.
o Direction: Moves food in one direction (down the digestive tract).
o Purpose: Facilitates the movement of food from the mouth to the stomach and
through the intestines.
o Example: The movement of food from the oesophagus to the stomach.
2. Antiperistalsis:
o Definition: The reverse movement of peristalsis, where muscle contractions
move food backward in the digestive tract.
 o Direction: Moves food in the opposite direction (upward, away from the
stomach).
o Purpose: Often occurs in vomiting, where the contents of the stomach are
expelled.
o Example: The reverse flow of stomach contents during vomiting.

Differences Between Spermatogenesis and Oogenesis

1. Spermatogenesis (Formation of sperm cells):
o Location: Occurs in the testes.
o Process:
1. Spermatogonia (diploid cells) undergo mitosis.
2. Primary spermatocytes (haploid) undergo meiosis I to form secondary
spermatocytes.
3. Secondary spermatocytes undergo meiosis II to form spermatids.
4. Spermatids mature into spermatozoa (sperm).
o Outcome: Four functional sperm cells from one spermatogonium.
o Timing: Continuous process from puberty onward.
o Function: Male gamete (sperm) production for reproduction.
2. Oogenesis (Formation of egg cells):
o Location: Occurs in the ovaries.
o Process:
1. Oogonia (diploid cells) undergo mitosis and become primary oocytes.
2. Primary oocytes undergo meiosis I but stop at prophase I until puberty.
3. Each month, one primary oocyte completes meiosis I, forming a
secondary oocyte and a polar body.
4. The secondary oocyte completes meiosis II only if fertilized, forming
an ovum and another polar body.
o Outcome: One functional ovum and polar bodies (non-functional).
o Timing: Begins before birth, resumes at puberty, and continues monthly until
menopause.
o Function: Female gamete (egg) production for reproduction.

Differences Between DNA and Chromosomes

1. DNA (Deoxyribonucleic Acid):
 o Structure: Double-helix structure composed of nucleotides (sugar, phosphate,
and nitrogenous bases).
o Function: Stores genetic information that codes for proteins and governs
cellular functions.
o Location: Found in the nucleus of eukaryotic cells and in the cytoplasm of
prokaryotes.
2. Chromosomes:
o Structure: Thread-like structures made of tightly coiled DNA and proteins
(histones).
o Function: Carry genetic information in a more organized form; allow DNA to
be distributed during cell division.
o Location: Found in the nucleus of eukaryotic cells during cell division.

Differences Between Larynx and Pharynx

1. Larynx:
o Location: Situated in the neck, below the pharynx and above the trachea.
o Function: Houses the vocal cords and is involved in sound production,
breathing, and protecting the airway during swallowing.
o Structure: Contains cartilage (including the thyroid cartilage), vocal cords,
and epiglottis.
2. Pharynx:
o Location: The throat region, behind the nose and mouth, leading to the
oesophagus and larynx.
o Function: Serves as a passage for both air and food, connects the mouth and
nasal cavity to the larynx and oesophagus.
o Structure: Divided into three sections: nasopharynx, oropharynx, and
laryngopharynx.

Differences Between Growth and Development

1. Growth:
o Definition: The increase in size, mass, or number of cells in an organism.
o Aspect: Quantitative.
o Example: Height increases during childhood.
2. Development:
o Definition: The process by which organisms progress through stages of life,
involving differentiation and maturation of cells, tissues, and organs.
 o Aspect: Qualitative, involves structural and functional changes.
o Example: Maturation of the brain and organs during childhood.

Differences Between RBCs and WBCs

1. Red Blood Cells (RBCs):
o Structure: Biconcave, disk-shaped cells without a nucleus.
o Function: Transport oxygen and carbon dioxide throughout the body via
haemoglobin.
o Lifespan: Approximately 120 days.
o Quantity: More numerous than WBCs.
o Location: Found in the blood vessels.
2. White Blood Cells (WBCs):
o Structure: Larger cells with a nucleus and various shapes (e.g., spherical or
amoeboid).
o Function: Part of the immune system, they protect the body against infections
and foreign invaders.
o Lifespan: Varies (from days to years, depending on type).
o Quantity: Fewer than RBCs.
o Location: Found in the blood, lymph, and tissues.
__________________________________________________________________________
Differences Between Arteries and Veins
1. Direction of Blood Flow:
o Arteries: Carry blood away from the heart (except pulmonary arteries).
o Veins: Carry blood toward the heart (except pulmonary veins).
2. Blood Pressure:
o Arteries: Have high blood pressure because they carry blood directly from
the heart.
o Veins: Have low blood pressure because they transport blood back to the
heart.
3. Wall Thickness:
o Arteries: Have thicker walls to handle high pressure.
o Veins: Have thinner walls as they deal with lower pressure.
___________________________________________________________________________
Differences Between Egestion and Excretion
1. Egestion:
o Definition: The removal of undigested food and waste from the digestive
system through the anus.
o Type of Waste: Involves non-metabolic waste (undigested food, fibre).
o Organs Involved: Occurs in the digestive system, specifically the rectum and
anus.
2. Excretion:
o Definition: The removal of metabolic waste produced by cells, like urea,
carbon dioxide, and salts.
o Type of Waste: Involves metabolic byproducts from bodily functions.
o Organs Involved: Occurs through the excretory system, including kidneys,
lungs, and skin.

Differences Between Homozygous and Heterozygous Genes

1. Homozygous:
o Definition: An organism has two identical alleles for a specific gene (e.g., AA
or aa).
o Inheritance: Both alleles come from the same parent or are identical in the
organism.
o Example: Having two dominant alleles (AA) or two recessive alleles (aa) for
a trait.
2. Heterozygous:
o Definition: An organism has two different alleles for a specific gene (e.g.,
Aa).
o Inheritance: The alleles are inherited from different parents, one being
dominant and the other recessive.
o Example: Having one dominant allele (A) and one recessive allele (a) for a
trait.

Differences Between Breathing and Respiration

1. Breathing:
o Definition: The physical process of taking air into and expelling air out of the
lungs.
o Purpose: Involves the intake of oxygen and the removal of carbon dioxide
from the body.
 o Location: Takes place in the lungs and is controlled by the respiratory
muscles (diaphragm, rib muscles).
2. Respiration:
o Definition: The biochemical process where cells convert oxygen and glucose
into energy, producing carbon dioxide and water as byproducts.
o Purpose: Provides energy for cellular functions.
o Location: Occurs in cells, specifically in the mitochondria.

Differences Between Aerobic and Anaerobic Respiration

1. Aerobic Respiration:
o Definition: Respiration that occurs in the presence of oxygen.
o Energy Yield: Produces more energy (ATP) per molecule of glucose.
o Byproducts: Produces carbon dioxide and water as byproducts.
o Example: Cellular respiration in animals and plants.
2. Anaerobic Respiration:
o Definition: Respiration that occurs without oxygen.
o Energy Yield: Produces less energy (ATP) per molecule of glucose.
o Byproducts: Produces lactic acid (in animals) or ethanol and carbon
dioxide (in yeast).
o Example: Muscle cells during intense exercise or yeast fermentation.

Definitions
1. Hormones: Chemical signals produced by glands that control body functions like
growth, metabolism, and mood.
2. Hypothalamus: A brain part that controls hunger, temperature, and releases hormones
to manage other glands.
3. Pituitary Gland: A small gland in the brain that controls important processes like
growth and reproduction through hormone release.
4. Endocrine Theory: The idea that hormones, released by glands, regulate various
body functions.
5. Hypothesis: A testable prediction or explanation based on observations and existing
knowledge.
6. Fossils: Preserved remains or traces of ancient life, showing how species have
evolved over time.
 7. Genotype: The genetic makeup of an organism, the set of genes inherited from its
parents.
8. Phenotype: The physical traits or characteristics of an organism, such as eye colour
or height.
9. Allele: Different versions of a gene that can influence traits, like blue or brown eyes.
10. Genes: Segments of DNA that provide instructions for making proteins and
determining traits.
11. Mutation: A change in the DNA sequence that can lead to new traits or genetic
diversity.
12. Karyotype: The complete set of chromosomes in an organism, used to study genetic
material.
13. Phenotypic Plasticity: The ability of an organism to change its traits in response to
environmental factors.
14. Structure of Genes: Genes are made of DNA, which consists of sequences of
nucleotides encoding proteins.
15. Genetics: The study of how traits are inherited from parents to offspring through
genes.
16. Species: A group of organisms that can interbreed and produce fertile offspring.
17. Population: A group of the same species living and interacting in a specific area.
18. Mendel’s Laws: Principles of inheritance discovered by Gregor Mendel that explain
how traits are passed to offspring.
19. Law of Segregation: The rule that each individual has two alleles for each trait, and
these alleles separate during reproduction.
20. Law of Independent Assortment: The principle that genes for different traits are
inherited independently of each other.

Disorders:
1. Chronic Bronchitis:
• Definition: Chronic inflammation of the bronchial tubes, which causes a persistent cough
and mucus production.

• Symptoms: Persistent cough with mucus, wheezing, shortness of breath, fatigue.

• Causes: Smoking is the most common cause; long-term exposure to irritants like pollution or
dust can also contribute.

• Treatment: Medication to reduce inflammation (bronchodilators, corticosteroids), quitting

smoking, and pulmonary rehabilitation.
 • Complications: Can lead to more severe conditions like emphysema or Chronic Obstructive
Pulmonary Disease (COPD).

2. Chronic Obstructive Pulmonary Disease (COPD):

• Definition: A progressive lung disease that makes breathing difficult, commonly caused by
long-term exposure to harmful substances like cigarette smoke.

• Symptoms: Shortness of breath, chronic cough, wheezing, chest tightness, frequent

respiratory infections.

• Causes: Smoking, long-term exposure to air pollution, chemical fumes, or dust.

• Treatment: Smoking cessation, bronchodilators, steroids, oxygen therapy, and pulmonary

rehabilitation.

• Complications: Increased risk of lung infections, respiratory failure, heart problems.

3. Emphysema:
• Definition: A type of COPD where the air sacs (alveoli) in the lungs are damaged, leading to
difficulty in exhaling air and reduced oxygen intake.

• Symptoms: Shortness of breath, chronic cough, wheezing, fatigue, weight loss.

• Causes: Long-term smoking is the primary cause; exposure to pollutants and genetic factors
(e.g., alpha-1 antitrypsin deficiency) can also contribute.

• Treatment: Smoking cessation, inhaled medications (bronchodilators, corticosteroids),

oxygen therapy, and in severe cases, lung surgery or transplant.

• Complications: Respiratory failure, heart problems, and increased risk of lung infections.

4. Lung Cancer:
• Definition: A type of cancer that starts in the lungs, often due to abnormal cell growth.

• Symptoms: Persistent cough, chest pain, shortness of breath, coughing up blood, weight
loss, fatigue.

• Causes: Smoking is the leading cause, though environmental factors (radon exposure,
second-hand smoke, air pollution) and genetic factors can also contribute.

• Treatment: Surgery, chemotherapy, radiation therapy, targeted therapy, immunotherapy.

• Complications: Spread to other organs (metastasis), difficulty breathing, pain, and

respiratory failure.

5. Atherosclerosis:
• Definition: A condition where plaque (fatty deposits) builds up inside the arteries, narrowing
and hardening them, restricting blood flow.
 • Symptoms: Often no symptoms in early stages, but can lead to chest pain, stroke, heart
attack, or peripheral artery disease.

• Causes: Poor diet (high in fats and cholesterol), lack of exercise, smoking, high blood
pressure, diabetes, and genetic factors.

• Treatment: Lifestyle changes (healthy diet, exercise, smoking cessation), medications

(statins, blood pressure meds), and surgery (bypass, angioplasty).

• Complications: Heart attack, stroke, peripheral artery disease, kidney damage.

6. Varicose Veins:
• Definition: Swollen, twisted veins, usually in the legs, caused by weakened or damaged
valves in the veins that allow blood to flow backward.

• Symptoms: Visible, bulging veins, aching, swelling, cramps, and heaviness in the legs.

• Causes: Age, pregnancy, obesity, prolonged standing, family history, and hormonal changes.

• Treatment: Lifestyle changes (exercise, weight management), compression stockings,

sclerotherapy, laser treatments, or surgery for severe cases.

• Complications: Blood clots, skin ulcers, bleeding from the veins.