Q21. What is the function of platelets in the blood?
A) Carrying oxygen
B) Fighting infection
C) Clotting blood
D) Removing waste
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Correct Answer: C) Clotting blood
Explanation: Platelets are a component of blood whose function is to react to bleeding from blood vessel injury by clumping, thereby initiating a blood clot.
Q22. Which hormone regulates the sleep-wake cycle?
A) Adrenaline
B) Cortisol
C) Melatonin
D) Serotonin
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Correct Answer: C) Melatonin
Explanation: Melatonin is produced by the pineal gland and regulates the sleep-wake cycle by signaling the body to prepare for sleep.
Q23. What is the main structural protein found in skin and connective tissues?
A) Keratin
B) Elastin
C) Collagen
D) Myosin
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Correct Answer: C) Collagen
Explanation: Collagen is the main structural protein in the extracellular space in the various connective tissues, being responsible for skin elasticity and strength.
Q24. Which part of the heart is responsible for pumping oxygenated blood to the body?
A) Right atrium
B) Right ventricle
C) Left atrium
D) Left ventricle
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Correct Answer: D) Left ventricle
Explanation: The left ventricle pumps oxygenated blood to the body, making it one of the heart’s most crucial components.
Q25. What is the term for the involuntary contraction of the diaphragm followed by a rapid closure of the vocal cords?
A) Cough
B) Sneeze
C) Yawn
D) Hiccup
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Correct Answer: D) Hiccup
Explanation: A hiccup is an involuntary contraction of the diaphragm, which is followed by the closing of the vocal cords, producing the characteristic “hic” sound.
Q26. Which gland is known as the “master gland” of the endocrine system?
A) Thyroid gland
B) Adrenal gland
C) Pineal gland
D) Pituitary gland
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Correct Answer: D) Pituitary gland
Explanation: The pituitary gland is often referred to as the “master gland” because it controls several other hormone glands in your body, including the thyroid and adrenals, the ovaries and testicles.
Q27. What is the primary function of the respiratory system?
A) To digest food
B) To circulate blood
C) To breathe
D) To filter toxins
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Correct Answer: C) To breathe
Explanation: The primary function of the respiratory system is to bring in oxygen for the body’s needs and expel carbon dioxide.
Q28. Which part of the human body is primarily responsible for detoxification?
A) Heart
B) Lungs
C) Liver
D) Kidneys
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Correct Answer: C) Liver
Explanation: The liver is responsible for detoxifying various metabolites, synthesizing proteins, and producing biochemicals necessary for digestion.
Q29. What is the function of the cerebrum?
A) Regulating balance
B) Controlling heart rate
C) Processing sensory information
D) Coordinating muscle movements
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Correct Answer: C) Processing sensory information
Explanation: The cerebrum is the largest part of the brain and is responsible for processing sensory information and enabling conscious thought, including reasoning, emotions, and learning.
Q30. Which blood type is considered the universal donor?
A) A+
B) B-
C) AB+
D) O-
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Correct Answer: D) O-
Explanation: Type O- blood is considered the universal donor type because it is compatible with any blood type in transfusions.