Q.1 Which part of the human brain controls voluntary movements?
Cerebellum
Medulla oblongata
Cerebrum
Hypothalamus
Explanation - The cerebrum is responsible for voluntary motor activities, sensory perception, memory, and reasoning.
Correct answer is: Cerebrum
Q.2 Which hormone regulates blood sugar levels by decreasing it?
Glucagon
Insulin
Adrenaline
Cortisol
Explanation - Insulin is secreted by beta cells of the pancreas and helps cells absorb glucose, lowering blood sugar levels.
Correct answer is: Insulin
Q.3 The primary function of alveoli in the lungs is to:
Filter dust particles
Exchange gases
Produce mucus
Store oxygen
Explanation - Alveoli are tiny air sacs where oxygen is absorbed into the blood and carbon dioxide is expelled.
Correct answer is: Exchange gases
Q.4 Which blood cells are primarily responsible for clotting?
Red blood cells
White blood cells
Platelets
Plasma cells
Explanation - Platelets are cell fragments that help in blood clotting to prevent excessive bleeding.
Correct answer is: Platelets
Q.5 Which part of the nephron is mainly responsible for filtration of blood?
Proximal tubule
Bowman's capsule
Loop of Henle
Collecting duct
Explanation - The Bowman's capsule encloses the glomerulus and filters blood plasma into the nephron.
Correct answer is: Bowman's capsule
Q.6 Which of the following is a type of white blood cell involved in antibody production?
Neutrophils
Eosinophils
Lymphocytes
Basophils
Explanation - B-lymphocytes produce antibodies as part of the adaptive immune response.
Correct answer is: Lymphocytes
Q.7 Which vitamin is essential for the synthesis of prothrombin?
Vitamin A
Vitamin D
Vitamin K
Vitamin E
Explanation - Vitamin K is necessary for the production of prothrombin, a key clotting factor in blood.
Correct answer is: Vitamin K
Q.8 Which structure in the heart prevents backflow of blood into the atria?
Semilunar valves
Atrioventricular valves
Chordae tendineae
Septum
Explanation - The atrioventricular (tricuspid and mitral) valves prevent backflow of blood from ventricles to atria.
Correct answer is: Atrioventricular valves
Q.9 Which enzyme in saliva begins the digestion of starch?
Pepsin
Amylase
Lipase
Trypsin
Explanation - Salivary amylase breaks down starch into maltose in the mouth.
Correct answer is: Amylase
Q.10 The pacemaker of the heart is:
Atrioventricular node
Purkinje fibers
Sinoatrial node
Bundle of His
Explanation - The SA node initiates electrical impulses that regulate the heartbeat, hence called the pacemaker.
Correct answer is: Sinoatrial node
Q.11 Which part of the digestive system is mainly responsible for water absorption?
Stomach
Small intestine
Large intestine
Esophagus
Explanation - The large intestine absorbs water and electrolytes, forming solid feces.
Correct answer is: Large intestine
Q.12 Which gas is primarily transported by red blood cells?
Carbon dioxide
Oxygen
Nitrogen
Hydrogen
Explanation - Hemoglobin in red blood cells binds to oxygen and transports it from lungs to tissues.
Correct answer is: Oxygen
Q.13 Which hormone is secreted by adrenal medulla in response to stress?
Cortisol
Adrenaline
Thyroxine
Insulin
Explanation - Adrenaline increases heart rate, blood pressure, and energy availability during stress.
Correct answer is: Adrenaline
Q.14 Which part of the brain regulates balance and coordination?
Cerebrum
Cerebellum
Medulla
Hypothalamus
Explanation - The cerebellum controls posture, balance, and smooth coordination of voluntary movements.
Correct answer is: Cerebellum
Q.15 Which component of blood transports hormones and nutrients?
Plasma
Red blood cells
White blood cells
Platelets
Explanation - Plasma is the liquid portion of blood, carrying hormones, nutrients, and waste products.
Correct answer is: Plasma
Q.16 Which of the following is responsible for the acidic environment in the stomach?
Mucus
Pepsin
Hydrochloric acid
Bile
Explanation - HCl secreted by parietal cells provides an acidic pH to activate pepsin and kill microbes.
Correct answer is: Hydrochloric acid
Q.17 Which organ produces bile?
Pancreas
Gallbladder
Liver
Stomach
Explanation - The liver produces bile which aids in the emulsification of fats.
Correct answer is: Liver
Q.18 Which of the following hormones increases blood calcium levels?
Calcitonin
Parathyroid hormone
Insulin
Glucagon
Explanation - Parathyroid hormone increases blood calcium by stimulating bone resorption and calcium absorption.
Correct answer is: Parathyroid hormone
Q.19 Which type of muscle is involuntary and non-striated?
Skeletal muscle
Cardiac muscle
Smooth muscle
All muscles
Explanation - Smooth muscles are found in internal organs and blood vessels and are involuntary and non-striated.
Correct answer is: Smooth muscle
Q.20 Which structure connects muscles to bones?
Ligaments
Tendons
Cartilage
Fascia
Explanation - Tendons are strong connective tissues that attach muscles to bones.
Correct answer is: Tendons
Q.21 Which part of the ear is responsible for detecting sound vibrations?
Cochlea
Semicircular canals
Pinna
Auditory canal
Explanation - The cochlea in the inner ear converts sound vibrations into nerve impulses.
Correct answer is: Cochlea
Q.22 Which hormone regulates the sleep-wake cycle?
Melatonin
Insulin
Adrenaline
Thyroxine
Explanation - Melatonin secreted by the pineal gland regulates circadian rhythms and sleep patterns.
Correct answer is: Melatonin
Q.23 Which organ in the human body detoxifies harmful substances?
Kidney
Liver
Lungs
Spleen
Explanation - The liver metabolizes and detoxifies chemicals and drugs, making them easier to excrete.
Correct answer is: Liver
Q.24 Which part of the respiratory system prevents food from entering the trachea?
Epiglottis
Pharynx
Larynx
Bronchi
Explanation - The epiglottis covers the trachea during swallowing, preventing food from entering the airway.
Correct answer is: Epiglottis
Q.25 Which component of blood carries oxygen to tissues?
Plasma
White blood cells
Platelets
Red blood cells
Explanation - Red blood cells contain hemoglobin, which binds and transports oxygen to tissues.
Correct answer is: Red blood cells