UNIT – IV: Nervous, Reproductive & Endocrine Systems
System
Topics Covered
Nervous System
Basic Anatomy of Brain and Spinal Cord
Major Types of Cells in Nervous System
Neurons
Divisions of Nervous System
Mechanism of Nerve Impulse
Reproductive System
Male & Female Reproductive Systems
Sex Hormones
Secondary Sexual Characteristics
Spermatogenesis
Oogenesis
Menstrual Cycle
Pregnancy
Menopause
Contraceptive Measures
Endocrine System
Introduction to Glands and Their Secretions
Classification of Glands
Endocrine & Exocrine Hormones:
Release
Secretion
Action
UNIT – III Cardio Vascular System Question of
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UNIT – UNIT – III Cardio Vascular System
MCQ with explanation.
MCQ 1: What is the basic structural and functional unit of the nervous system?
A. Glial cell
B. Neuron
C. Dendrite
D. Axon Correct Answer: B. Neuron Explanation: Neurons are the primary cells that transmit electrical signals throughout the nervous system.
MCQ 2: Which part of the brain is responsible for coordination and balance?
A. Cerebrum
B. Medulla
C. Cerebellum
D. Hypothalamus Correct Answer: C. Cerebellum Explanation: The cerebellum coordinates voluntary movements and maintains balance and posture.
MCQ 3: What protects the spinal cord?
A. Skull
B. Rib cage
C. Vertebral column
D. Pelvis Correct Answer: C. Vertebral column Explanation: The spinal cord is protected by the vertebral column, which encases it in bone.
MCQ 4: What type of cell supports and nourishes neurons?
A. Epithelial cells
B. Glial cells
C. Myocytes
D. Platelets Correct Answer: B. Glial cells Explanation: Glial cells provide structural support and nourishment to neurons.
MCQ 5: Which division of the nervous system includes the brain and spinal cord?
A. Autonomic
B. Somatic
C. Peripheral
D. Central Correct Answer: D. Central Explanation: The central nervous system (CNS) consists of the brain and spinal cord.
MCQ 6: How is a nerve impulse transmitted across a synapse?
A. Through blood
B. Via neurotransmitters
C. By electric wires
D. Through lymph Correct Answer: B. Via neurotransmitters Explanation: Neurotransmitters are chemicals that transmit signals across the synaptic gap.
MCQ 7: Which gland regulates the entire endocrine system?
A. Adrenal gland
B. Pituitary gland
C. Thyroid gland
D. Pancreas Correct Answer: B. Pituitary gland Explanation: The pituitary gland is called the "master gland" because it controls other endocrine glands.
MCQ 8: Which hormone is responsible for regulating blood sugar levels?
A. Adrenaline
B. Insulin
C. Thyroxine
D. Estrogen Correct Answer: B. Insulin Explanation: Insulin is secreted by the pancreas and helps lower blood sugar levels.
MCQ 9: What type of gland releases hormones directly into the blood?
A. Endocrine
B. Exocrine
C. Salivary
D. Sebaceous Correct Answer: A. Endocrine Explanation: Endocrine glands release hormones directly into the bloodstream without using ducts.
MCQ 10: Where does spermatogenesis occur?
A. Epididymis
B. Prostate gland
C. Seminal vesicle
D. Testes Correct Answer: D. Testes Explanation: Spermatogenesis is the process of sperm production, and it occurs in the testes.
MCQ 11: What is the function of the ovaries in females?
A. Produce insulin
B. Produce eggs and hormones
C. Filter urine
D. Support embryo Correct Answer: B. Produce eggs and hormones Explanation: The ovaries release ova (eggs) and secrete female sex hormones such as estrogen and progesterone.
MCQ 12: Which hormone triggers ovulation during the menstrual cycle?
A. FSH
B. LH
C. Estrogen
D. Progesterone Correct Answer: B. LH Explanation: Luteinizing hormone (LH) causes the release of a mature egg from the ovary.
MCQ 13: What is the average length of a normal menstrual cycle?
A. 15 days
B. 21 days
C. 28 days
D. 35 days Correct Answer: C. 28 days Explanation: A typical menstrual cycle lasts about 28 days, though it can vary from person to person.
MCQ 14: Which hormone is essential for maintaining pregnancy?
A. Testosterone
B. Estrogen
C. Progesterone
D. Oxytocin Correct Answer: C. Progesterone Explanation: Progesterone maintains the uterine lining and supports early pregnancy.
MCQ 15: What marks the end of a woman’s reproductive years?
A. Menarche
B. Ovulation
C. Fertilization
D. Menopause Correct Answer: D. Menopause Explanation: Menopause marks the cessation of menstrual cycles and the end of fertility.
MCQ 16: What is the main function of testosterone in males?
A. Regulate sugar
B. Increase immunity
C. Develop male secondary sexual characteristics
D. Maintain blood pressure Correct Answer: C. Develop male secondary sexual characteristics Explanation: Testosterone is responsible for features like facial hair, deep voice, and muscle development in males.
MCQ 17: Which contraceptive method is hormonal?
A. Condom
B. Copper IUD
C. Birth control pill
D. Diaphragm Correct Answer: C. Birth control pill Explanation: Birth control pills contain synthetic hormones to prevent ovulation.
MCQ 18: Which endocrine gland secretes adrenaline?
A. Thyroid
B. Pituitary
C. Adrenal gland
D. Pancreas Correct Answer: C. Adrenal gland Explanation: The adrenal medulla secretes adrenaline during stress to prepare the body for 'fight or flight.'
MCQ 19: What is the function of the hypothalamus in hormone regulation?
A. Stores blood
B. Releases oxygen
C. Controls pituitary gland
D. Pumps blood Correct Answer: C. Controls pituitary gland Explanation: The hypothalamus links the nervous and endocrine systems and controls the release of pituitary hormones.
MCQ 20: What is oogenesis?
A. Development of male gametes
B. Production of red blood cells
C. Formation of female gametes
D. Release of urine Correct Answer: C. Formation of female gametes Explanation: Oogenesis is the process of egg (ovum) formation in the female ovary.
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UNIT – III Cardio Vascular System
MCQ with explanation.
MCQ 1: What is the primary function of the heart?
A. Produce red blood cells
B. Filter blood
C. Pump blood throughout the body
D. Digest nutrients Correct Answer: C. Pump blood throughout the body Explanation: The heart is a muscular organ responsible for pumping blood through the circulatory system.
MCQ 2: Which chamber of the heart receives deoxygenated blood from the body?
A. Right atrium
B. Left atrium
C. Right ventricle
D. Left ventricle Correct Answer: A. Right atrium Explanation: The right atrium receives oxygen-poor blood from the body via the superior and inferior vena cava.
MCQ 3: Which blood vessels carry blood away from the heart?
A. Veins
B. Arteries
C. Capillaries
D. Venules Correct Answer: B. Arteries Explanation: Arteries are thick-walled blood vessels that carry oxygenated blood away from the heart (except pulmonary artery).
MCQ 4: Which valve prevents backflow of blood from the left ventricle to the left atrium?
A. Tricuspid valve
B. Pulmonary valve
C. Mitral valve
D. Aortic valve Correct Answer: C. Mitral valve Explanation: The mitral (bicuspid) valve ensures one-way blood flow from the left atrium to the left ventricle.
MCQ 5: What is the function of the SA node in the heart?
A. Contracts the ventricles
B. Initiates heartbeat
C. Circulates blood
D. Filters blood Correct Answer: B. Initiates heartbeat Explanation: The sinoatrial (SA) node is the natural pacemaker of the heart that generates electrical impulses.
MCQ 6: Which part of the heart pumps blood to the lungs?
A. Right atrium
B. Left atrium
C. Right ventricle
D. Left ventricle Correct Answer: C. Right ventricle Explanation: The right ventricle pumps deoxygenated blood into the pulmonary artery toward the lungs.
MCQ 7: What is the contraction phase of the cardiac cycle called?
A. Diastole
B. Systole
C. Resting phase
D. Filtration Correct Answer: B. Systole Explanation: Systole is when the heart muscles contract to pump blood into the arteries.
MCQ 8: What causes the 'lub-dub' sounds of the heart?
A. Contraction of myocardium
B. Opening of valves
C. Closure of heart valves
D. Blood turbulence Correct Answer: C. Closure of heart valves Explanation: The "lub" is caused by AV valves closing; the "dub" by semilunar valves closing.
MCQ 9: What is the normal blood pressure reading for an adult?
A. 160/100 mmHg
B. 120/80 mmHg
C. 140/90 mmHg
D. 100/60 mmHg Correct Answer: B. 120/80 mmHg Explanation: 120/80 mmHg is considered normal for a healthy adult.
MCQ 10: Which blood vessels allow gas and nutrient exchange with tissues?
A. Arteries
B. Veins
C. Capillaries
D. Venules Correct Answer: C. Capillaries Explanation: Capillaries are tiny vessels where exchange of oxygen, CO₂, and nutrients occurs.
MCQ 11: What is the main organ of the respiratory system?
A. Trachea
B. Lungs
C. Diaphragm
D. Bronchi Correct Answer: B. Lungs Explanation: The lungs are the primary site of gas exchange during respiration.
MCQ 12: What is the primary muscle involved in breathing?
A. Intercostal muscles
B. Diaphragm
C. Rectus abdominis
D. Pectoral muscle Correct Answer: B. Diaphragm Explanation: The diaphragm contracts and flattens to expand the chest cavity during inhalation.
MCQ 13: Where does gas exchange occur in the lungs?
A. Bronchi
B. Bronchioles
C. Alveoli
D. Trachea Correct Answer: C. Alveoli Explanation: Alveoli are tiny air sacs where oxygen and carbon dioxide are exchanged.
MCQ 14: Which brain region regulates breathing?
A. Cerebrum
B. Cerebellum
C. Medulla oblongata
D. Hypothalamus Correct Answer: C. Medulla oblongata Explanation: The medulla oblongata controls the rate and depth of respiration.
MCQ 15: What is external respiration?
A. Cellular respiration
B. Breathing in and out
C. Gas exchange between blood and lungs
D. Gas exchange between cells and blood Correct Answer: C. Gas exchange between blood and lungs Explanation: External respiration is the exchange of gases between alveoli and pulmonary capillaries.
MCQ 16: What is tidal volume?
A. Maximum inhalation volume
B. Volume after forced expiration
C. Normal breath volume
D. Total lung capacity Correct Answer: C. Normal breath volume Explanation: Tidal volume is the amount of air inhaled and exhaled during normal breathing.
MCQ 17: Which structure connects the larynx to the bronchi?
A. Trachea
B. Alveoli
C. Pharynx
D. Esophagus Correct Answer: A. Trachea Explanation: The trachea (windpipe) carries air from the larynx to the bronchi.
MCQ 18: What is the role of hemoglobin in respiration?
A. Transport glucose
B. Fight infection
C. Carry oxygen
D. Remove toxins Correct Answer: C. Carry oxygen Explanation: Hemoglobin binds with oxygen in red blood cells and transports it to body tissues.
MCQ 19: Which part of the respiratory system prevents food from entering the airway?
A. Uvula
B. Larynx
C. Epiglottis
D. Pharynx Correct Answer: C. Epiglottis Explanation: The epiglottis is a flap that covers the larynx during swallowing.
MCQ 20: Which part of the respiratory system is responsible for producing sound?
A. Bronchi
B. Trachea
C. Larynx
D. Pharynx Correct Answer: C. Larynx
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UNIT – II Digestive system
MCQ with explanation.
MCQ 1: Which of the following is the first part of the gastrointestinal (GI) tract?
A. Stomach
B. Esophagus
C. Small intestine
D. Mouth Correct Answer: D. Mouth Explanation: The mouth is the entry point of the GI tract where mechanical and chemical digestion begins.
MCQ 2: What is the function of the esophagus?
A. Absorption of nutrients
B. Digestion of fats
C. Transport of food to the stomach
D. Secretion of enzymes Correct Answer: C. Transport of food to the stomach Explanation: The esophagus is a muscular tube that propels food from the mouth to the stomach via peristalsis.
MCQ 3: Which of the following organs secretes bile?
A. Stomach
B. Liver
C. Pancreas
D. Gall bladder Correct Answer: B. Liver Explanation: The liver produces bile, which aids in the digestion and absorption of fats.
MCQ 4: Which part of the small intestine is responsible for most nutrient absorption?
A. Duodenum
B. Jejunum
C. Ileum
D. Cecum Correct Answer: B. Jejunum Explanation: The jejunum has a highly folded surface area with villi and microvilli to maximize absorption of nutrients.
MCQ 5: What is the primary role of the large intestine?
A. Protein digestion
B. Fat absorption
C. Water and electrolyte absorption
D. Enzyme secretion Correct Answer: C. Water and electrolyte absorption Explanation: The large intestine absorbs water and electrolytes and compacts fecal material.
MCQ 6: Which enzyme breaks down starch into maltose?
A. Lipase
B. Pepsin
C. Amylase
D. Trypsin Correct Answer: C. Amylase Explanation: Amylase, found in saliva and pancreatic juice, digests starch into maltose.
MCQ 7: What is the main function of the gall bladder?
A. Produces insulin
B. Filters toxins
C. Stores and concentrates bile
D. Produces digestive enzymes Correct Answer: C. Stores and concentrates bile Explanation: The gall bladder stores bile from the liver and releases it into the duodenum during digestion.
MCQ 8: Which organ secretes digestive enzymes into the small intestine?
A. Liver
B. Stomach
C. Pancreas
D. Esophagus Correct Answer: C. Pancreas Explanation: The pancreas secretes digestive enzymes into the duodenum that aid in digestion of carbohydrates, proteins, and fats.
MCQ 9: Which digestive enzyme is secreted by the stomach?
A. Pepsin
B. Lipase
C. Trypsin
D. Amylase Correct Answer: A. Pepsin Explanation: Pepsin is a proteolytic enzyme secreted in the stomach that digests proteins.
MCQ 10: Which structure prevents food from entering the windpipe?
A. Uvula
B. Epiglottis
C. Pharynx
D. Larynx Correct Answer: B. Epiglottis Explanation: The epiglottis is a flap that closes over the trachea during swallowing to prevent food from entering the airway.
MCQ 11: What is the primary structural and functional unit of the kidney?
A. Glomerulus
B. Nephron
C. Ureter
D. Renal pelvis Correct Answer: B. Nephron Explanation: The nephron is the microscopic structure in the kidney that filters blood and forms urine.
MCQ 12: Where does glomerular filtration occur?
A. Proximal tubule
B. Loop of Henle
C. Glomerulus
D. Collecting duct Correct Answer: C. Glomerulus Explanation: Glomerular filtration takes place in the glomerulus, where blood plasma is filtered into the Bowman's capsule.
MCQ 13: Which part of the nephron reabsorbs the majority of filtered nutrients and water?
A. Collecting duct
B. Distal tubule
C. Proximal convoluted tubule
D. Loop of Henle Correct Answer: C. Proximal convoluted tubule Explanation: Most reabsorption of water, glucose, and electrolytes occurs in the proximal convoluted tubule.
MCQ 14: What is the function of the Loop of Henle?
A. Filtration of blood
B. Secretion of urine
C. Concentration of urine
D. Bile formation Correct Answer: C. Concentration of urine Explanation: The Loop of Henle creates a concentration gradient in the medulla to enable water reabsorption and urine concentration.
MCQ 15: Which hormone increases water reabsorption in the kidneys?
A. Aldosterone
B. Insulin
C. Antidiuretic hormone (ADH)
D. Cortisol Correct Answer: C. Antidiuretic hormone (ADH) Explanation: ADH increases water reabsorption in the collecting ducts, reducing urine output.
MCQ 16: What is the primary waste product excreted in urine?
A. Glucose
B. Urea
C. Creatine
D. Bile Correct Answer: B. Urea Explanation: Urea is the main nitrogenous waste product formed from protein metabolism and excreted in urine.
MCQ 17: Which vessel brings blood into the glomerulus for filtration?
A. Renal vein
B. Efferent arteriole
C. Afferent arteriole
D. Ureter Correct Answer: C. Afferent arteriole Explanation: The afferent arteriole brings blood to the glomerulus where filtration begins.
MCQ 18: Which of the following is NOT part of the excretory system?
A. Ureter
B. Bladder
C. Large intestine
D. Urethra Correct Answer: C. Large intestine Explanation: The large intestine belongs to the digestive system and is not involved in urine formation or excretion.
MCQ 19: Where is urine stored before excretion?
A. Kidney
B. Ureter
C. Bladder
D. Urethra Correct Answer: C. Bladder Explanation: The urinary bladder temporarily stores urine before it is excreted through the urethra.
MCQ 20: What is the function of the urethra?
A. Produces urine
B. Transports urine from kidneys
C. Stores urine
D. Conducts urine outside the body Correct Answer: D. Conducts urine outside the body Explanation: The urethra is a tube that transports urine from the bladder to the outside of the body during urination.
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General Human Anatomy & Physiology-II
MCQ with explanation.
MCQ 1: Which of the following is not a digestive organ?
A. Liver
B. Pancreas
C. Kidney
D. Small intestine Correct Answer: C. Kidney Explanation: The kidney is part of the excretory system, not the digestive system. It filters blood to form urine. The liver, pancreas, and small intestine are all involved in digestion.
MCQ 2: Which of the following is not a pancreatic enzyme?
A. Trypsin
B. Amylase
C. Pepsin
D. Lipase Correct Answer: C. Pepsin Explanation: Pepsin is produced in the stomach, not the pancreas. The pancreas produces trypsin (proteins), amylase (carbohydrates), and lipase (fats).
MCQ 3: What is the main constituent of urine?
A. Glucose
B. Urea
C. Protein
D. Bile Correct Answer: B. Urea Explanation: Urea is the major nitrogenous waste product in urine, formed from the breakdown of proteins in the liver.
MCQ 4: Urine is stored in:
A. Ureter
B. Kidney
C. Urethra
D. Urinary bladder Correct Answer: D. Urinary bladder Explanation: The urinary bladder stores urine until it is expelled from the body through the urethra.
MCQ 5: What is the main function of bile in digestion?
A. Digest proteins
B. Neutralize stomach acid
C. Emulsify fats
D. Absorb glucose Correct Answer: C. Emulsify fats Explanation: Bile breaks down large fat droplets into smaller ones (emulsification), aiding in fat digestion.
MCQ 6: Which part of the nephron does most of the reabsorption of water occur?
A. Bowman's capsule
B. Loop of Henle
C. Distal convoluted tubule
D. Proximal convoluted tubule Correct Answer: D. Proximal convoluted tubule Explanation: The proximal tubule reabsorbs the majority of filtered water, salts, and nutrients.
MCQ 7: Digestion of food starts from:
A. Stomach
B. Small intestine
C. Mouth
D. Esophagus Correct Answer: C. Mouth Explanation: Digestion begins in the mouth with chewing and the action of salivary amylase on carbohydrates.
MCQ 8: Which organ absorbs water from food?
A. Stomach
B. Small intestine
C. Large intestine
D. Esophagus Correct Answer: C. Large intestine Explanation: The large intestine absorbs water and electrolytes from indigestible food matter.
MCQ 9: Which of the following is not a part of the small intestine?
A. Duodenum
B. Jejunum
C. Ileum
D. Colon Correct Answer: D. Colon Explanation: The colon is part of the large intestine, not the small intestine.
MCQ 10: ADH primarily affects which part of the nephron to regulate water reabsorption?
A. Bowman's capsule
B. Proximal tubule
C. Loop of Henle
D. Collecting duct Correct Answer: D. Collecting duct Explanation: ADH increases the permeability of the collecting duct to water, enhancing water reabsorption.
MCQ 11: Which part of the digestive system is responsible for absorbing most of the nutrients?
A. Stomach
B. Small intestine
C. Large intestine
D. Liver Correct Answer: B. Small intestine Explanation: The small intestine (especially jejunum and ileum) absorbs most nutrients from digested food.
MCQ 12: Protein is digested by which enzymes?
A. Amylase and Lipase
B. Pepsin and Trypsin
C. Maltase and Sucrase
D. Lactase and Peptidase Correct Answer: B. Pepsin and Trypsin Explanation: Pepsin (from the stomach) and trypsin (from the pancreas) break down proteins into peptides.
MCQ 13: Which is not a step in urine formation in the nephron?
A. Filtration
B. Reabsorption
C. Secretion
D. Evaporation Correct Answer: D. Evaporation Explanation: Evaporation is not involved in urine formation. The process involves filtration, reabsorption, and secretion.
MCQ 14: What is the role of hydrochloric acid in the stomach?
A. Absorb proteins
B. Neutralize enzymes
C. Kill bacteria and activate pepsin
D. Emulsify fats Correct Answer: C. Kill bacteria and activate pepsin Explanation: HCl creates an acidic environment that activates pepsinogen into pepsin and kills pathogens.
MCQ 15: What is the function of villi in the small intestine?
A. Produce bile
B. Absorb nutrients
C. Store waste
D. Digest proteins Correct Answer: B. Absorb nutrients Explanation: Villi increase surface area in the small intestine, aiding in the absorption of nutrients.
MCQ 16: Which organ filters wastes from the blood?
A. Liver
B. Kidney
C. Lungs
D. Bladder Correct Answer: B. Kidney Explanation: Kidneys filter waste, excess salts, and water from the blood to form urine.
MCQ 17: What is the functional unit of the kidney?
A. Neuron
B. Nephron
C. Alveolus
D. Tubule Correct Answer: B. Nephron Explanation: The nephron is the microscopic structural and functional unit of the kidney.
MCQ 18: Which hormone increases water reabsorption in collecting ducts?
A. Aldosterone
B. ADH
C. Renin
D. Insulin Correct Answer: B. ADH Explanation: Antidiuretic hormone (ADH) makes collecting ducts more permeable to water, conserving body water.
MCQ 19: Which organ carries urine from kidneys to the bladder?
A. Urethra
B. Nephron
C. Ureter
D. Renal artery Correct Answer: C. Ureter Explanation: Ureters are tubes that transport urine from each kidney to the bladder.
MCQ 20: Which hormone stimulates the production of pancreatic juice and bicarbonate?
A. Gastrin
B. Secretin
C. Insulin
D. Pepsin Correct Answer: B. Secretin Explanation: Secretin is released in response to acidic chyme and stimulates the pancreas to release bicarbonate-rich fluid.
MCQ 21: Which of the following bones is part of the axial skeleton?
A. Femur
B. Humerus
C. Sternum
D. Pelvis Correct Answer: C. Sternum Explanation: The sternum (breastbone) is part of the axial skeleton, which includes the skull, vertebral column, and thoracic cage.
MCQ 22: Which type of bone cell is responsible for breaking down bone tissue?
A. Osteoblast
B. Osteocyte
C. Osteoclast
D. Chondrocyte Correct Answer: C. Osteoclast Explanation: Osteoclasts break down bone tissue during bone resorption and remodeling.
MCQ 23: What is the outer layer of a bone called?
A. Periosteum
B. Endosteum
C. Marrow
D. Cartilage Correct Answer: A. Periosteum Explanation: The periosteum is a dense membrane covering the outer surface of bones except at the joints.
MCQ 24: Which of the following is a fibrous joint?
A. Skull suture
B. Knee
C. Shoulder
D. Elbow Correct Answer: A. Skull suture Explanation: Skull sutures are immovable fibrous joints found between bones of the skull.
MCQ 25: Which joint type allows rotation around a single axis?
A. Ball and socket
B. Saddle
C. Hinge
D. Pivot Correct Answer: D. Pivot Explanation: Pivot joints, such as the joint between the atlas and axis vertebrae, allow rotational movement.
MCQ 26: Which bone protects the brain?
A. Sternum
B. Femur
C. Cranium
D. Scapula Correct Answer: C. Cranium Explanation: The cranium (part of the skull) protects the brain.
MCQ 27: What initiates muscle contraction at the neuromuscular junction?
A. Calcium
B. Sodium
C. Acetylcholine
D. Potassium Correct Answer: C. Acetylcholine Explanation: Acetylcholine is the neurotransmitter released at the neuromuscular junction to initiate muscle contraction.
MCQ 28: Which connective tissue connects muscles to bones?
A. Ligaments
B. Cartilage
C. Tendons
D. Fascia Correct Answer: C. Tendons Explanation: Tendons attach muscles to bones and transmit the force needed for movement.
MCQ 29: Which muscle tissue is involuntary and found in the walls of internal organs?
A. Skeletal muscle
B. Smooth muscle
C. Cardiac muscle
D. Voluntary muscle Correct Answer: B. Smooth muscle Explanation: Smooth muscle is involuntary and found in walls of internal organs such as the stomach and intestines.
MCQ 30: Which protein blocks the myosin-binding sites on actin in a resting muscle?
A. Troponin
B. Tropomyosin
C. Myoglobin
D. Creatine Correct Answer: B. Tropomyosin Explanation: Tropomyosin covers the binding sites on actin filaments and prevents muscle contraction when the muscle is at rest.
MCQ 31: Which part of the skeleton includes the limbs?
A. Axial skeleton
B. Appendicular skeleton
C. Vertebral column
D. Skull Correct Answer: B. Appendicular skeleton Explanation: The appendicular skeleton includes the bones of the limbs and girdles (shoulder and pelvic).
MCQ 32: Which bone is the longest in the human body?
A. Humerus
B. Tibia
C. Femur
D. Radius Correct Answer: C. Femur Explanation: The femur, or thigh bone, is the longest and strongest bone in the human body.
MCQ 33: What type of joint is found in the shoulder and hip?
A. Hinge
B. Ball and socket
C. Pivot
D. Gliding Correct Answer: B. Ball and socket Explanation: Ball and socket joints allow movement in multiple directions and are found in the shoulder and hip.
MCQ 34: Which structure stores calcium in a muscle cell?
A. Sarcolemma
B. Myofibril
C. Sarcoplasmic reticulum
D. T-tubule Correct Answer: C. Sarcoplasmic reticulum Explanation: The sarcoplasmic reticulum stores calcium ions, which are essential for muscle contraction.
MCQ 35: Which muscle type has striations and is under voluntary control?
A. Smooth
B. Skeletal
C. Cardiac
D. Involuntary Correct Answer: B. Skeletal Explanation: Skeletal muscle is striated and controlled voluntarily.
MCQ 36: What is the functional unit of a skeletal muscle fiber?
A. Myofibril
B. Sarcomere
C. Fascicle
D. Actin Correct Answer: B. Sarcomere Explanation: The sarcomere is the basic contractile unit of muscle fiber, composed of actin and myosin filaments.
MCQ 37: What connects two bones at a joint?
A. Tendon
B. Ligament
C. Cartilage
D. Fascia Correct Answer: B. Ligament Explanation: Ligaments are fibrous tissues that connect bones at joints and help stabilize them.
MCQ 38: What causes the 'lub-dub' sound in the heart, often confused with muscles?
A. Contraction of muscles
B. Opening of valves
C. Closing of valves
D. Movement of blood Correct Answer: C. Closing of valves Explanation: Though related to the cardiovascular system, the heart sound is due to the closing of valves—not muscles.
MCQ 39: Which joint provides the least range of motion?
A. Hinge joint
B. Ball and socket
C. Fibrous joint
D. Gliding joint Correct Answer: C. Fibrous joint Explanation: Fibrous joints (like skull sutures) are immovable and provide minimal range of motion.
MCQ 40: Which part of the bone contains red bone marrow?
A. Compact bone
B. Yellow marrow
C. Periosteum
D. Spongy bone Correct Answer: D. Spongy bone Explanation: Spongy bone, found at the ends of long bones and inside flat bones, contains red marrow where blood cells are produced.
MCQ 41: Which of the following is the first part of the gastrointestinal (GI) tract?
A. Stomach
B. Esophagus
C. Small intestine
D. Mouth Correct Answer: D. Mouth Explanation: The mouth is the entry point of the GI tract where mechanical and chemical digestion begins.
MCQ 42: What is the function of the esophagus?
A. Absorption of nutrients
B. Digestion of fats
C. Transport of food to the stomach
D. Secretion of enzymes Correct Answer: C. Transport of food to the stomach Explanation: The esophagus is a muscular tube that propels food from the mouth to the stomach via peristalsis.
MCQ 43: Which of the following organs secretes bile?
A. Stomach
B. Liver
C. Pancreas
D. Gall bladder Correct Answer: B. Liver Explanation: The liver produces bile, which aids in the digestion and absorption of fats.
MCQ 44: Which part of the small intestine is responsible for most nutrient absorption?
A. Duodenum
B. Jejunum
C. Ileum
D. Cecum Correct Answer: B. Jejunum Explanation: The jejunum has a highly folded surface area with villi and microvilli to maximize absorption of nutrients.
MCQ 45: What is the primary role of the large intestine?
A. Protein digestion
B. Fat absorption
C. Water and electrolyte absorption
D. Enzyme secretion Correct Answer: C. Water and electrolyte absorption Explanation: The large intestine absorbs water and electrolytes and compacts fecal material.
MCQ 46: Which enzyme breaks down starch into maltose?
A. Lipase
B. Pepsin
C. Amylase
D. Trypsin Correct Answer: C. Amylase Explanation: Amylase, found in saliva and pancreatic juice, digests starch into maltose.
MCQ 47: What is the main function of the gall bladder?
A. Produces insulin
B. Filters toxins
C. Stores and concentrates bile
D. Produces digestive enzymes Correct Answer: C. Stores and concentrates bile Explanation: The gall bladder stores bile from the liver and releases it into the duodenum during digestion.
MCQ 48: Which organ secretes digestive enzymes into the small intestine?
A. Liver
B. Stomach
C. Pancreas
D. Esophagus Correct Answer: C. Pancreas Explanation: The pancreas secretes digestive enzymes into the duodenum that aid in digestion of carbohydrates, proteins, and fats.
MCQ 49: Which digestive enzyme is secreted by the stomach?
A. Pepsin
B. Lipase
C. Trypsin
D. Amylase Correct Answer: A. Pepsin Explanation: Pepsin is a proteolytic enzyme secreted in the stomach that digests proteins.
MCQ 50: Which structure prevents food from entering the windpipe?
A. Uvula
B. Epiglottis
C. Pharynx
D. Larynx Correct Answer: B. Epiglottis Explanation: The epiglottis is a flap that closes over the trachea during swallowing to prevent food from entering the airway.
MCQ 51: What is the primary structural and functional unit of the kidney?
A. Glomerulus
B. Nephron
C. Ureter
D. Renal pelvis Correct Answer: B. Nephron Explanation: The nephron is the microscopic structure in the kidney that filters blood and forms urine.
MCQ 52: Where does glomerular filtration occur?
A. Proximal tubule
B. Loop of Henle
C. Glomerulus
D. Collecting duct Correct Answer: C. Glomerulus Explanation: Glomerular filtration takes place in the glomerulus, where blood plasma is filtered into the Bowman's capsule.
MCQ 53: Which part of the nephron reabsorbs the majority of filtered nutrients and water?
A. Collecting duct
B. Distal tubule
C. Proximal convoluted tubule
D. Loop of Henle Correct Answer: C. Proximal convoluted tubule Explanation: Most reabsorption of water, glucose, and electrolytes occurs in the proximal convoluted tubule.
MCQ 54: What is the function of the Loop of Henle?
A. Filtration of blood
B. Secretion of urine
C. Concentration of urine
D. Bile formation Correct Answer: C. Concentration of urine Explanation: The Loop of Henle creates a concentration gradient in the medulla to enable water reabsorption and urine concentration.
MCQ 55: Which hormone increases water reabsorption in the kidneys?
A. Aldosterone
B. Insulin
C. Antidiuretic hormone (ADH)
D. Cortisol Correct Answer: C. Antidiuretic hormone (ADH) Explanation: ADH increases water reabsorption in the collecting ducts, reducing urine output.
MCQ 56: What is the primary waste product excreted in urine?
A. Glucose
B. Urea
C. Creatine
D. Bile Correct Answer: B. Urea Explanation: Urea is the main nitrogenous waste product formed from protein metabolism and excreted in urine.
MCQ 57: Which vessel brings blood into the glomerulus for filtration?
A. Renal vein
B. Efferent arteriole
C. Afferent arteriole
D. Ureter Correct Answer: C. Afferent arteriole Explanation: The afferent arteriole brings blood to the glomerulus where filtration begins.
MCQ 58: Which of the following is NOT part of the excretory system?
A. Ureter
B. Bladder
C. Large intestine
D. Urethra Correct Answer: C. Large intestine Explanation: The large intestine belongs to the digestive system and is not involved in urine formation or excretion.
MCQ 59: Where is urine stored before excretion?
A. Kidney
B. Ureter
C. Bladder
D. Urethra Correct Answer: C. Bladder Explanation: The urinary bladder temporarily stores urine before it is excreted through the urethra.
MCQ 60: What is the function of the urethra?
A. Produces urine
B. Transports urine from kidneys
C. Stores urine
D. Conducts urine outside the body Correct Answer: D. Conducts urine outside the body Explanation: The urethra is a tube that transports urine from the bladder to the outside of the body during urination.
MCQ 61: What is the primary function of the heart?
A. Produce red blood cells
B. Filter blood
C. Pump blood throughout the body
D. Digest nutrients Correct Answer: C. Pump blood throughout the body Explanation: The heart is a muscular organ responsible for pumping blood through the circulatory system.
MCQ 62: Which chamber of the heart receives deoxygenated blood from the body?
A. Right atrium
B. Left atrium
C. Right ventricle
D. Left ventricle Correct Answer: A. Right atrium Explanation: The right atrium receives oxygen-poor blood from the body via the superior and inferior vena cava.
MCQ 63: Which blood vessels carry blood away from the heart?
A. Veins
B. Arteries
C. Capillaries
D. Venules Correct Answer: B. Arteries Explanation: Arteries are thick-walled blood vessels that carry oxygenated blood away from the heart (except pulmonary artery).
MCQ 64: Which valve prevents backflow of blood from the left ventricle to the left atrium?
A. Tricuspid valve
B. Pulmonary valve
C. Mitral valve
D. Aortic valve Correct Answer: C. Mitral valve Explanation: The mitral (bicuspid) valve ensures one-way blood flow from the left atrium to the left ventricle.
MCQ 65: What is the function of the SA node in the heart?
A. Contracts the ventricles
B. Initiates heartbeat
C. Circulates blood
D. Filters blood Correct Answer: B. Initiates heartbeat Explanation: The sinoatrial (SA) node is the natural pacemaker of the heart that generates electrical impulses.
MCQ 66: Which part of the heart pumps blood to the lungs?
A. Right atrium
B. Left atrium
C. Right ventricle
D. Left ventricle Correct Answer: C. Right ventricle Explanation: The right ventricle pumps deoxygenated blood into the pulmonary artery toward the lungs.
MCQ 67: What is the contraction phase of the cardiac cycle called?
A. Diastole
B. Systole
C. Resting phase
D. Filtration Correct Answer: B. Systole Explanation: Systole is when the heart muscles contract to pump blood into the arteries.
MCQ 68: What causes the 'lub-dub' sounds of the heart?
A. Contraction of myocardium
B. Opening of valves
C. Closure of heart valves
D. Blood turbulence Correct Answer: C. Closure of heart valves Explanation: The "lub" is caused by AV valves closing; the "dub" by semilunar valves closing.
MCQ 69: What is the normal blood pressure reading for an adult?
A. 160/100 mmHg
B. 120/80 mmHg
C. 140/90 mmHg
D. 100/60 mmHg Correct Answer: B. 120/80 mmHg Explanation: 120/80 mmHg is considered normal for a healthy adult.
MCQ 70: Which blood vessels allow gas and nutrient exchange with tissues?
A. Arteries
B. Veins
C. Capillaries
D. Venules Correct Answer: C. Capillaries Explanation: Capillaries are tiny vessels where exchange of oxygen, CO₂, and nutrients occurs.
MCQ 71: What is the main organ of the respiratory system?
A. Trachea
B. Lungs
C. Diaphragm
D. Bronchi Correct Answer: B. Lungs Explanation: The lungs are the primary site of gas exchange during respiration.
MCQ 72: What is the primary muscle involved in breathing?
A. Intercostal muscles
B. Diaphragm
C. Rectus abdominis
D. Pectoral muscle Correct Answer: B. Diaphragm Explanation: The diaphragm contracts and flattens to expand the chest cavity during inhalation.
MCQ 73: Where does gas exchange occur in the lungs?
A. Bronchi
B. Bronchioles
C. Alveoli
D. Trachea Correct Answer: C. Alveoli Explanation: Alveoli are tiny air sacs where oxygen and carbon dioxide are exchanged.
MCQ 74: Which brain region regulates breathing?
A. Cerebrum
B. Cerebellum
C. Medulla oblongata
D. Hypothalamus Correct Answer: C. Medulla oblongata Explanation: The medulla oblongata controls the rate and depth of respiration.
MCQ 75: What is external respiration?
A. Cellular respiration
B. Breathing in and out
C. Gas exchange between blood and lungs
D. Gas exchange between cells and blood Correct Answer: C. Gas exchange between blood and lungs Explanation: External respiration is the exchange of gases between alveoli and pulmonary capillaries.
MCQ 76: What is tidal volume?
A. Maximum inhalation volume
B. Volume after forced expiration
C. Normal breath volume
D. Total lung capacity Correct Answer: C. Normal breath volume Explanation: Tidal volume is the amount of air inhaled and exhaled during normal breathing.
MCQ 77: Which structure connects the larynx to the bronchi?
A. Trachea
B. Alveoli
C. Pharynx
D. Esophagus Correct Answer: A. Trachea Explanation: The trachea (windpipe) carries air from the larynx to the bronchi.
MCQ 78: What is the role of hemoglobin in respiration?
A. Transport glucose
B. Fight infection
C. Carry oxygen
D. Remove toxins Correct Answer: C. Carry oxygen Explanation: Hemoglobin binds with oxygen in red blood cells and transports it to body tissues.
MCQ 79: Which part of the respiratory system prevents food from entering the airway?
A. Uvula
B. Larynx
C. Epiglottis
D. Pharynx Correct Answer: C. Epiglottis Explanation: The epiglottis is a flap that covers the larynx during swallowing.
MCQ 80: Which part of the respiratory system is responsible for producing sound?
A. Bronchi
B. Trachea
C. Larynx
D. Pharynx Correct Answer: C. Larynx Explanation: The larynx, or voice box, contains vocal cords that vibrate to produce sound.
MCQ 81: What is the basic structural and functional unit of the nervous system?
A. Glial cell
B. Neuron
C. Dendrite
D. Axon Correct Answer: B. Neuron Explanation: Neurons are the primary cells that transmit electrical signals throughout the nervous system.
MCQ 82: Which part of the brain is responsible for coordination and balance?
A. Cerebrum
B. Medulla
C. Cerebellum
D. Hypothalamus Correct Answer: C. Cerebellum Explanation: The cerebellum coordinates voluntary movements and maintains balance and posture.
MCQ 83: What protects the spinal cord?
A. Skull
B. Rib cage
C. Vertebral column
D. Pelvis Correct Answer: C. Vertebral column Explanation: The spinal cord is protected by the vertebral column, which encases it in bone.
MCQ 84: What type of cell supports and nourishes neurons?
A. Epithelial cells
B. Glial cells
C. Myocytes
D. Platelets Correct Answer: B. Glial cells Explanation: Glial cells provide structural support and nourishment to neurons.
MCQ 85: Which division of the nervous system includes the brain and spinal cord?
A. Autonomic
B. Somatic
C. Peripheral
D. Central Correct Answer: D. Central Explanation: The central nervous system (CNS) consists of the brain and spinal cord.
MCQ 86: How is a nerve impulse transmitted across a synapse?
A. Through blood
B. Via neurotransmitters
C. By electric wires
D. Through lymph Correct Answer: B. Via neurotransmitters Explanation: Neurotransmitters are chemicals that transmit signals across the synaptic gap.
MCQ 87: Which gland regulates the entire endocrine system?
A. Adrenal gland
B. Pituitary gland
C. Thyroid gland
D. Pancreas Correct Answer: B. Pituitary gland Explanation: The pituitary gland is called the "master gland" because it controls other endocrine glands.
MCQ 88: Which hormone is responsible for regulating blood sugar levels?
A. Adrenaline
B. Insulin
C. Thyroxine
D. Estrogen Correct Answer: B. Insulin Explanation: Insulin is secreted by the pancreas and helps lower blood sugar levels.
MCQ 89: What type of gland releases hormones directly into the blood?
A. Endocrine
B. Exocrine
C. Salivary
D. Sebaceous Correct Answer: A. Endocrine Explanation: Endocrine glands release hormones directly into the bloodstream without using ducts.
MCQ 90: Where does spermatogenesis occur?
A. Epididymis
B. Prostate gland
C. Seminal vesicle
D. Testes Correct Answer: D. Testes Explanation: Spermatogenesis is the process of sperm production, and it occurs in the testes.
MCQ 91: What is the function of the ovaries in females?
A. Produce insulin
B. Produce eggs and hormones
C. Filter urine
D. Support embryo Correct Answer: B. Produce eggs and hormones Explanation: The ovaries release ova (eggs) and secrete female sex hormones such as estrogen and progesterone.
MCQ 92: Which hormone triggers ovulation during the menstrual cycle?
A. FSH
B. LH
C. Estrogen
D. Progesterone Correct Answer: B. LH Explanation: Luteinizing hormone (LH) causes the release of a mature egg from the ovary.
MCQ 93: What is the average length of a normal menstrual cycle?
A. 15 days
B. 21 days
C. 28 days
D. 35 days Correct Answer: C. 28 days Explanation: A typical menstrual cycle lasts about 28 days, though it can vary from person to person.
MCQ 94: Which hormone is essential for maintaining pregnancy?
A. Testosterone
B. Estrogen
C. Progesterone
D. Oxytocin Correct Answer: C. Progesterone Explanation: Progesterone maintains the uterine lining and supports early pregnancy.
MCQ 95: What marks the end of a woman’s reproductive years?
A. Menarche
B. Ovulation
C. Fertilization
D. Menopause Correct Answer: D. Menopause Explanation: Menopause marks the cessation of menstrual cycles and the end of fertility.
MCQ 96: What is the main function of testosterone in males?
A. Regulate sugar
B. Increase immunity
C. Develop male secondary sexual characteristics
D. Maintain blood pressure Correct Answer: C. Develop male secondary sexual characteristics Explanation: Testosterone is responsible for features like facial hair, deep voice, and muscle development in males.
MCQ 97: Which contraceptive method is hormonal?
A. Condom
B. Copper IUD
C. Birth control pill
D. Diaphragm Correct Answer: C. Birth control pill Explanation: Birth control pills contain synthetic hormones to prevent ovulation.
MCQ 98: Which endocrine gland secretes adrenaline?
A. Thyroid
B. Pituitary
C. Adrenal gland
D. Pancreas Correct Answer: C. Adrenal gland Explanation: The adrenal medulla secretes adrenaline during stress to prepare the body for 'fight or flight.'
MCQ 99: What is the function of the hypothalamus in hormone regulation?
A. Stores blood
B. Releases oxygen
C. Controls pituitary gland
D. Pumps blood Correct Answer: C. Controls pituitary gland Explanation: The hypothalamus links the nervous and endocrine systems and controls the release of pituitary hormones.
MCQ 100: What is oogenesis?
A. Development of male gametes
B. Production of red blood cells
C. Formation of female gametes
D. Release of urine Correct Answer: C. Formation of female gametes Explanation: Oogenesis is the process of egg (ovum) formation in the female ovary.
