Science Olympiad : Advance Biology MCQ set - 6


Science Olympiad : Advance Biology MCQ practice with Answers set - 6


Q. How many chambers are there in the human heart ?


Ans: 4 chambers
Explanation: The heart has two atria and two ventricles.


Q. Which chamber pumps oxygenated blood to the body ?


Ans: Left ventricle
Explanation: It pumps oxygen-rich blood into the aorta.


Q. Which chamber receives deoxygenated blood ?


Ans: Right atrium
Explanation: It collects deoxygenated blood from the body.


Q. Which is the largest artery in the human body ?


Ans: Aorta
Explanation: The aorta distributes oxygenated blood to the entire body.


Q. Which blood cells transport oxygen ?


Ans: Red Blood Cells (RBCs)
Explanation: RBCs carry oxygen through hemoglobin.


Q. Which protein in RBC carries oxygen ?


Ans: Hemoglobin
Explanation: Hemoglobin binds oxygen molecules in the lungs.


Q. Which type of blood cells fight infections ?


Ans: White Blood Cells (WBCs)
Explanation: WBCs destroy pathogens and protect immunity.


Q. Average blood volume in an adult human ?


Ans: 5–6 liters
Explanation: An adult has approximately 7–8% of body weight as blood.


Q. Universal donor blood group ?


Ans: O negative (O⁻)
Explanation: O⁻ blood can be given to all groups.


Q. Universal recipient blood group ?


Ans: AB positive (AB⁺)
Explanation: AB⁺ can receive blood from all groups.


Q. Which organ produces insulin ?


Ans: Pancreas
Explanation: Pancreatic β-cells secrete insulin.


Q. Which hormone regulates blood sugar ?


Ans: Insulin
Explanation: Insulin lowers blood glucose levels.


Q. Which hormone is called the ‘fight or flight’ hormone ?


Ans: Adrenaline
Explanation: It prepares the body for emergency action.


Q. Which gland is called the ‘master gland’?


Ans: Pituitary gland
Explanation: It controls other endocrine glands.


Q. Which gland regulates metabolism ?


Ans: Thyroid gland
Explanation: Thyroid hormones regulate body metabolism.


Q. Which gland secretes melatonin ?


Ans: Pineal gland
Explanation: Melatonin controls sleep–wake cycles.


Q. Which gland controls calcium level in blood ?


Ans: Parathyroid gland
Explanation: It releases PTH, which increases blood calcium.


Q. Which part of the brain controls breathing & heartbeat ?


Ans: Medulla oblongata
Explanation: It regulates vital involuntary functions.


Q. Which part of the brain controls posture & balance ?


Ans: Cerebellum
Explanation: It coordinates muscle movement and balance.


Q. Largest part of the human brain ?


Ans: Cerebrum
Explanation: It controls thinking, memory, vision, and intelligence.


Q. Functional unit of the nervous system ?


Ans: Neuron
Explanation: Neurons transmit nerve impulses throughout the body.


Q. Which part of neuron receives signals ?


Ans: Dendrites
Explanation: Dendrites receive impulses from other neurons.


Q. Which part of neuron sends signals ?


Ans: Axon
Explanation: Axons carry impulses away from the neuron body.


Q. Which fluid cushions the brain and spinal cord ?


Ans: Cerebrospinal fluid (CSF)
Explanation: CSF protects the CNS from shock and nourishes it.


Q. Which membrane surrounds and protects brain & spinal cord ?


Ans: Meninges
Explanation: The meninges (dura, arachnoid, pia mater) form protective layers.