SECTION – A

10 x 2 = 20

1. Define the terms layer and broiler.

• Layer: A layer is a hen specifically bred and raised for egg production. They are typically smaller in size and have a high egg-laying capacity.
• Broiler: A broiler is a chicken bred and raised primarily for meat production. They are characterized by rapid growth and a larger body size compared to layers.

2. Distinguish between Cortical and Juxtamedullary nephrons.

• Cortical nephrons: These are the most common type, located primarily in the cortex of the kidney. They have short loops of Henle that extend only a short distance into the medulla.

• Juxtamedullary nephrons: These have long loops of Henle that extend deep into the medulla. They play a crucial role in concentrating urine and maintaining water balance in the body.

3. What is triad system?

The triad system is a structural arrangement found in skeletal muscle fibers. It consists of:

• T-tubule (Transverse Tubule): An invagination of the sarcolemma (muscle cell membrane) that penetrates deep into the muscle fiber.
• Two Terminal Cisternae: Enlarged regions of the sarcoplasmic reticulum (a network of interconnected tubules that store calcium ions) located adjacent to the T-tubule.

The triad system plays a crucial role in the excitation-contraction coupling process, ensuring rapid and synchronized muscle contraction.

4. What do you know about arborvitae?

Arborvitae refers to the tree of life. In the context of anatomy, it specifically refers to the white matter tracts within the cerebellum. These tracts resemble branches of a tree, hence the name. They connect different regions of the cerebellar cortex and play a vital role in coordinating movement and balance.

5. What are the functions of Sertoli cells of the seminiferous tubules and the Leydig cells in man?

• Sertoli Cells:

  • Provide structural and nutritional support to developing sperm cells.
  • Secrete substances that regulate spermatogenesis.
  • Form the blood-testis barrier, which isolates developing sperm cells from the immune system.

• Leydig Cells:

  • Produce and secrete testosterone, the primary male sex hormone.
  • Testosterone plays a crucial role in the development and maintenance of male secondary sexual characteristics and sperm production.

6. What is amniocentesis? Name any two disorders that can be detected by amniocentesis.

• Amniocentesis: It is a prenatal diagnostic procedure where a small amount of amniotic fluid is withdrawn from the amniotic sac surrounding the developing fetus.

• Amniotic fluid contains fetal cells and can be analyzed to detect certain genetic and chromosomal abnormalities.

• Two disorders detectable by amniocentesis:

  • Down Syndrome: A genetic disorder caused by an extra copy of chromosome 21.
  • Spina Bifida: A neural tube defect where the spinal cord fails to develop properly.

7. Define Atavism with an example.

• Atavism: It refers to the reappearance of ancestral traits in an individual that were not present in the immediate ancestors.

• Example: The presence of a tail in a human baby is considered an atavistic trait, as it is a characteristic found in our distant ancestors but not typically seen in modern humans.

8. What is meant by genetic load? Give an example.

• Genetic Load: It refers to the presence of harmful or deleterious alleles within a population’s gene pool. These alleles can cause genetic disorders or reduce an individual’s fitness.

• Example: In a population, the presence of alleles that cause cystic fibrosis contributes to the genetic load of that population.

9. Explain the term ‘hypophysation’.

• Hypophysation: It refers to the process of surgically removing the pituitary gland. It is a medical procedure that is sometimes performed to treat certain types of tumors or hormonal disorders.

10. Distinguish between absorption and assimilation.

• Absorption: It is the process of taking substances into the body. In the context of digestion, it refers to the uptake of nutrients from the digestive tract into the bloodstream.

• Assimilation: It is the process of incorporating absorbed substances into the body’s tissues and using them for various metabolic processes, such as growth, repair, and energy production.

SECTION – B

Note: Answer any SIX questions in 20 lines each.

6 x 4 = 24

11. What are the functions of Liver?

The liver is a vital organ with numerous functions in the body. Some of its key functions include:

• Detoxification: The liver plays a crucial role in detoxifying the blood by removing harmful substances such as alcohol, drugs, and toxins. It converts these substances into less harmful compounds that can be excreted from the body.

• Bile Production: The liver produces bile, a fluid that is essential for the digestion and absorption of fats. Bile emulsifies fats, breaking them down into smaller droplets, which increases the surface area for digestion by enzymes.  

• Metabolism: The liver is involved in various metabolic processes, including carbohydrate metabolism, protein metabolism, and lipid metabolism. It stores glucose as glycogen, breaks down amino acids, and synthesizes cholesterol and other lipids.

• Storage: The liver stores essential nutrients such as vitamins (A, D, E, K) and minerals (iron, copper). It also stores glucose in the form of glycogen and releases it into the bloodstream when needed to maintain blood sugar levels.

• Immune Function: The liver plays a role in the body’s immune system by filtering out bacteria and other foreign substances from the blood. It also produces immune proteins that help to fight infections.

• Blood Clotting: The liver synthesizes proteins involved in blood clotting, such as fibrinogen and prothrombin. These proteins are essential for the formation of blood clots to stop bleeding.

12. Describe disorders of the Respiratory system.

The respiratory system can be affected by various disorders, leading to breathing difficulties and other health problems. Some of the common respiratory disorders include:

• Asthma: A chronic condition characterized by inflammation and narrowing of the airways, making it difficult to breathe. Symptoms include wheezing, coughing, chest tightness, and shortness of breath.  

   

• Chronic Obstructive Pulmonary Disease (COPD): A group of lung diseases, including chronic bronchitis and emphysema, that cause airflow obstruction and difficulty breathing. COPD is often caused by smoking.

• Pneumonia: An infection that inflames the air sacs in the lungs, often causing coughing, fever, and difficulty breathing. Pneumonia can be caused by bacteria, viruses, or fungi.

• Tuberculosis: A bacterial infection that primarily affects the lungs, causing coughing, fever, weight loss, and night sweats.

• Lung Cancer: Uncontrolled growth of abnormal cells in the lungs, often caused by smoking. Lung cancer is a leading cause of cancer deaths worldwide.

• Acute Respiratory Distress Syndrome (ARDS): A life-threatening condition characterized by fluid accumulation in the lungs, leading to severe breathing difficulties. ARDS can be caused by various factors, including severe infections, injuries, and certain medical conditions.

These are just a few examples of respiratory disorders. Other conditions that can affect the respiratory system include:

• Bronchitis: Inflammation of the bronchial tubes, causing coughing and mucus production.
• Influenza: A viral infection that can cause respiratory symptoms, including fever, cough, and sore throat.
• Cystic Fibrosis: A genetic disorder that affects the lungs and other organs, leading to mucus buildup and difficulty breathing.

It is important to seek medical attention if you experience any persistent respiratory symptoms. Early diagnosis and treatment can help manage respiratory disorders and prevent complications.

Note: These answers are provided within the 20-line limit. More detailed information can be found in medical textbooks and from healthcare professionals.

13. Draw a neat labelled diagram of the pelvic girdle.

(A labeled diagram of the pelvic girdle should be drawn here. It should include the following structures:

• Ilium: The largest and uppermost part of the hip bone.
• Ischium: The lower and posterior part of the hip bone.
• Pubis: The anterior part of the hip bone.
• Acetabulum: The socket in the hip bone that articulates with the head of the femur.
• Sacroiliac Joint: The joint between the ilium and the sacrum.
• Pubic Symphysis: The joint between the two pubic bones.

14. Write a note on Addison’s disease and Cushing’s syndrome.

• Addison’s Disease: This condition is caused by the insufficient production of cortisol and aldosterone by the adrenal glands. It is often due to an autoimmune attack on the adrenal cortex. Symptoms include fatigue, weakness, weight loss, low blood pressure, and skin pigmentation.

• Cushing’s Syndrome: This condition results from excessive exposure to cortisol, often due to an adrenal tumor or the use of glucocorticoid medications. Symptoms include weight gain, muscle weakness, high blood pressure, mood changes, and skin thinning.

15. Write a short note on B-cells.

B-cells are a type of lymphocyte (white blood cell) that play a crucial role in the humoral immune response. They function by producing antibodies, which are proteins that bind to specific antigens (foreign substances) and neutralize them. When a B-cell encounters its specific antigen, it differentiates into plasma cells, which produce large amounts of antibodies.  16. Write the salient features of ‘HGP’.

 

HGP stands for the Human Genome Project, an international scientific research project with the goal of determining the sequence of the human genome and identifying all of its genes. Some of the salient features of the HGP include:  

 

• It was a large-scale collaborative effort involving scientists from around the world.
• The project utilized advanced technologies such as DNA sequencing and bioinformatics.
• The HGP generated a vast amount of data that has revolutionized our understanding of human biology and genetics.
• The project has had significant implications for medicine, including the development of new diagnostic tools and therapies.

17. What is meant by genetic drift? Explain genetic drift citing the example of Founder effect.

Genetic drift is the random fluctuation of allele frequencies in a population due to chance events. It is particularly significant in small populations.

Founder Effect: One example of genetic drift is the founder effect. This occurs when a small group of individuals from a larger population colonizes a new area. The gene pool of the new population will be a subset of the original population’s gene pool. By chance, certain alleles may be overrepresented or underrepresented in the founding population, leading to significant changes in allele frequencies in the new population compared to the original population.

18. Discuss in brief about ‘Avian Flu’.

Avian flu, also known as bird flu, is a highly contagious viral infection that primarily affects birds. Some strains of avian flu can also infect humans, although human-to-human transmission is rare. Avian flu outbreaks can have significant economic impacts on the poultry industry and pose a potential threat to public health.

SECTION – C

Note: Answer any TWO questions in 60 lines each.

2 x 8 = 16

19. Describe the structure of the heart of man with the help of neat labelled diagram.

Structure of the Human Heart

The human heart is a muscular organ located in the chest cavity, slightly to the left. It’s responsible for pumping blood throughout the body. Here’s a breakdown of its structure:

• Four Chambers:

  • Atria (2): Two upper chambers (right atrium and left atrium). They receive blood.
  • Ventricles (2): Two lower chambers (right ventricle and left ventricle). They pump blood out of the heart.

• Valves: These ensure unidirectional blood flow.

  • Tricuspid Valve: Between the right atrium and right ventricle.
  • Pulmonary Valve: Between the right ventricle and the pulmonary artery.  

  • Mitral Valve (Bicuspid Valve): Between the left atrium and left ventricle.
  • Aortic Valve: Between the left ventricle and the aorta.

• Blood Vessels:

  • Superior and Inferior Vena Cava: Bring deoxygenated blood from the body to the right atrium.
  • Pulmonary Artery: Carries deoxygenated blood from the right ventricle to the lungs.
  • Pulmonary Veins: Bring oxygenated blood from the lungs to the left atrium.  

  • Aorta: The largest artery, carries oxygenated blood from the left ventricle to the body.

Diagram: (A labeled diagram of the human heart should be drawn here. It should include the four chambers, valves, and major blood vessels as mentioned above.)

20. Describe female reproductive system of a woman with the help of a labelled diagram.

Female Reproductive System

The female reproductive system is responsible for producing eggs, providing a site for fertilization and fetal development, and delivering the baby. It consists of the following organs:

• Ovaries: Two almond-shaped organs located in the pelvic cavity. They produce eggs (ova) and hormones like estrogen and progesterone.
• Fallopian Tubes: Two tubes that extend from the ovaries to the uterus. They transport the egg from the ovary to the uterus and are the site of fertilization.  

• Uterus: A muscular, pear-shaped organ where the fertilized egg implants and develops into a fetus.
• Cervix: The lower, narrow part of the uterus that opens into the vagina.
• Vagina: A muscular tube that connects the cervix to the external genitalia. It serves as the birth canal and receives the penis during intercourse.
• Vulva: The external genitalia, including the labia majora, labia minora, clitoris, and vaginal opening.

Diagram: (A labeled diagram of the female reproductive system should be drawn here. It should include the organs mentioned above.)

21. Describe chromosomal theory of sex determination.

The chromosomal theory of sex determination states that sex is determined by the presence or absence of specific sex chromosomes. In humans:

• Females have two X chromosomes (XX).
• Males have one X and one Y chromosome (XY).

The Y chromosome contains the SRY gene, which triggers the development of male characteristics. In the absence of the Y chromosome, female characteristics develop.

This theory explains the inheritance of sex-linked traits, which are traits controlled by genes located on the sex chromosomes.

Note: These are brief descriptions. More detailed explanations and diagrams can be found in biology textbooks and from healthcare professionals.