(SEM II) THEORY EXAMINATION 2021-22 HUMAN ANATOMY AND PHYSIOLOGY II

B.Pharm (Sem II) – Human Anatomy and Physiology II

Detailed Explanation of Questions and Answers

Human Anatomy and Physiology studies the structure and functions of the human body. Anatomy deals with the structural organization of organs, while physiology explains how these organs perform various biological functions. For pharmacy students, understanding these processes is important because medicines interact with different physiological systems in the body. 

Section A – Detailed Answers

Cerebrum

The cerebrum is the largest part of the brain and is responsible for higher mental functions such as thinking, memory, reasoning, and voluntary movements. It consists of two hemispheres known as the right and left cerebral hemispheres.

The outer layer of the cerebrum is called the cerebral cortex, which contains nerve cells responsible for processing sensory information and controlling motor activities. Different regions of the cerebrum are specialized for different functions such as vision, hearing, speech, and decision-making.

Glomerular Filtration Rate (GFR)

Glomerular filtration rate refers to the rate at which blood plasma is filtered through the glomeruli of the kidneys. It is an important indicator of kidney function.

The filtration process occurs when blood passes through tiny capillaries called glomeruli, allowing water and small molecules to pass into the renal tubules while retaining larger molecules such as proteins.

A normal GFR indicates that the kidneys are functioning properly in removing waste products and maintaining fluid balance.

Functions of Hormones

Hormones are chemical messengers produced by endocrine glands and released into the bloodstream. They regulate various physiological processes in the body.

Hormones control growth and development, regulate metabolism, maintain fluid balance, and influence reproductive functions. They also help coordinate activities of different organs and maintain homeostasis.

Examples include insulin, thyroid hormones, and adrenaline.

Gametogenesis

Gametogenesis is the process by which reproductive cells, known as gametes, are formed in the body. In males, this process is called spermatogenesis and occurs in the testes.

In females, gametogenesis is known as oogenesis and occurs in the ovaries. These processes involve specialized cell divisions called meiosis, which produce haploid cells containing half the number of chromosomes.

Role of Hydrochloric Acid in Digestion

Hydrochloric acid is secreted by parietal cells in the stomach. It plays several important roles in digestion.

The acid creates an acidic environment that activates digestive enzymes such as pepsin, which helps break down proteins into smaller peptides. It also helps kill harmful microorganisms present in food.

Hydrochloric acid also aids in the absorption of certain nutrients such as iron and vitamin B12.

Functions of Cerebellum

The cerebellum is located at the back of the brain and plays a crucial role in coordination of voluntary movements.

It helps maintain balance, posture, and muscle tone. The cerebellum also ensures that movements are smooth and coordinated.

Damage to the cerebellum may result in loss of balance and difficulty performing precise movements.

Neuron

A neuron is the basic structural and functional unit of the nervous system. It is responsible for transmitting nerve impulses throughout the body.

A typical neuron consists of three main parts: the cell body, dendrites, and axon. Dendrites receive signals from other neurons, while the axon carries impulses away from the cell body to other neurons or muscles.

Tidal Volume

Tidal volume refers to the amount of air that enters or leaves the lungs during a normal breathing cycle. In an average adult, tidal volume is approximately 500 milliliters.

This measurement helps evaluate respiratory efficiency and lung function.

Functions of Saliva

Saliva is produced by salivary glands and plays several roles in digestion and oral health.

It moistens food to facilitate swallowing, begins the digestion of carbohydrates through the enzyme amylase, and helps maintain oral hygiene by washing away food particles and bacteria.

Saliva also protects teeth and gums by maintaining proper pH balance.

Section B – Detailed Explanation

Autonomic Nervous System

The autonomic nervous system is a part of the peripheral nervous system that controls involuntary bodily functions such as heart rate, digestion, and respiratory rate.

It is divided into two main divisions: the sympathetic nervous system and the parasympathetic nervous system.

The sympathetic system prepares the body for stressful situations by increasing heart rate and blood pressure, while the parasympathetic system promotes relaxation and digestion.

Physiology of Digestion

Digestion is the process by which food is broken down into smaller molecules that can be absorbed by the body.

The process begins in the mouth where mechanical chewing and enzymatic digestion occur. Food then passes through the esophagus into the stomach, where gastric juices break down proteins.

In the small intestine, digestive enzymes from the pancreas and bile from the liver further break down nutrients. These nutrients are then absorbed into the bloodstream.

Endocrine System

The endocrine system consists of glands that produce hormones to regulate body functions. Major endocrine glands include the pituitary gland, thyroid gland, adrenal glands, pancreas, and gonads.

Hormones released by these glands regulate growth, metabolism, reproduction, and stress responses.

Hormones exert their effects by binding to specific receptors on target cells and triggering cellular responses.

Section C – Detailed Explanation

Mechanism of ATP Formation

ATP is produced primarily through cellular respiration in mitochondria. During this process, glucose is broken down through glycolysis, the citric acid cycle, and oxidative phosphorylation.

The energy released during these reactions is used to convert ADP and inorganic phosphate into ATP.

ATP serves as the main energy source for cellular activities such as muscle contraction, active transport, and biosynthesis.

Structure of Liver and Role of Bile

The liver is the largest internal organ in the body and performs many metabolic functions.

It produces bile, which helps digest fats by emulsifying large fat droplets into smaller ones. This process increases the efficiency of fat digestion by enzymes.

The liver also plays a role in detoxification, metabolism of nutrients, and storage of glycogen.

Nephron

The nephron is the functional unit of the kidney responsible for urine formation. Each kidney contains millions of nephrons.

A nephron consists of a glomerulus and a tubular system including the proximal tubule, loop of Henle, distal tubule, and collecting duct.

Through processes of filtration, reabsorption, and secretion, the nephron helps remove waste products and maintain fluid balance.

Menstrual Cycle

The menstrual cycle is a series of hormonal changes that occur in the female reproductive system.

It typically lasts about 28 days and consists of four phases: menstrual phase, follicular phase, ovulation phase, and luteal phase.

These phases are regulated by hormones such as estrogen, progesterone, follicle-stimulating hormone, and luteinizing hormone.

Conclusion

Human Anatomy and Physiology provides a comprehensive understanding of how the body functions and how different organ systems work together. This knowledge is essential for pharmacy students because drugs interact with various physiological systems.

Understanding these processes helps pharmacists understand disease mechanisms, drug actions, and therapeutic outcomes.