All Free Biology MCQs with Answers

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19,844 questions · page 809 of 993

  • A. People eat more nutritive food, therefore more RBCs are formed
  • B. People get pollution­ free air to breath and more oxygen is available
  • C. Atmospheric O2 level is less and hence more RBCs are needed to absorb the required amount of O2 to survive
  • D. There is more UV radiation which enhances RBC production

Explanation: A. People eat more nutritive food, therefore more RBCs are formed:This statement is not accurate.

Correct answer: Atmospheric O2 level is less and hence more RBCs are needed to absorb the required amount of O2 to survive
  • A. Oxygen
  • B. Chloroform
  • C. Carbon dioxide
  • D. Carbon monoxide.

Explanation: A. The patient has been inhaling polluted air containing unusually high content of oxygen: This statement is not accurate.

Correct answer: Carbon monoxide.
  • A. Shallower and slow
  • B. There is no effect on breathing
  • C. Slow and not deep
  • D. Faster and deeper.

Explanation: A. When CO2 concentration in blood increases, breathing becomes shallower and slow:This statement is accurate.

Correct answer: Faster and deeper.
  • A. 2000 kcal
  • B. 1000 kcal
  • C. 750 kcal
  • D. 2800 kcal.

Explanation: A: An average person not doing hard work requires energy per day about 2000 kcal: This statement is accurate.

Correct answer: 2000 kcal
  • A. Spleen
  • B. Liver
  • C. Gill
  • D. Lung

Explanation: All options are explained below. Option A is correct. a)Spleen: The spleen is a vital organ in the vertebrate circulatory system which…

Correct answer: Spleen
  • A. With the help of WBCs and blood serum
  • B. With the help of platelets and corpuscles
  • C. With the help of RBCs and blood plasma
  • D. With the help of RBCs and WBCs

Explanation: All options are explained below: a)With the help of WBCs and blood serum: White blood cells (WBCs) primarily play a role in the immune…

Correct answer: With the help of RBCs and blood plasma
  • A. Increase in number
  • B. Decrease in number
  • C. Increase in size
  • D. Decrease in size

Explanation: All options are explained below: a)Increase in number (Correct Option): This statement is accurate.

Correct answer: Increase in number
  • A. CO2 is continuously diffused through the tissues and is not allowed to accumulate
  • B. In CO2 transport, blood buffers play an important role
  • C. CO2 is absorbed by the leucocytes
  • D. CO2 combines with water to form H2CO3 which is neutralized by NaCO3 .

Explanation: All options are explained below: a)CO2 is continuously diffused through the tissues and is not allowed to accumulate:This statement is not…

Correct answer: In CO2 transport, blood buffers play an important role
  • A. In combination with haemoglobin only
  • B. Dissolved in blood plasma
  • C. In the form of bicarbonate ions
  • D. As carbaminohaemoglobin and as carbonic acid

Explanation: All options are explained below: a)in combination with haemoglobin only:This statement is not entirely accurate.

Correct answer: In the form of bicarbonate ions
  • A. Muscular walls of lung
  • B. Diaphragm
  • C. Costal muscles
  • D. Both (b) and (c).

Explanation: All options are explained below: a) Muscular walls of lung: The walls of the lungs themselves do not play a direct role in governing…

Correct answer: Both (b) and (c).
  • A. Cerebellum
  • B. Medulla oblongata
  • C. Cerebral peduncle
  • D. The vagus nerve.

Explanation: All options are explained below: a)Cerebellum:The cerebellum is primarily responsible for coordinating motor movements, balance, and…

Correct answer: Medulla oblongata
  • A. Plasma and Erythrocytes
  • B. Plasma
  • C. Erythrocytes
  • D. Erythrocytes and Leucocytes.

Explanation: All options are explained below: a) plasma and erythrocytes : In this option, it is suggested that carbon dioxide is transported from…

Correct answer: Plasma and Erythrocytes
  • A. Humans
  • B. Frog
  • C. Rabbit
  • D. Lizard.

Explanation: All options are explained below: a) Humans: In humans, the skin can play a limited role in respiration, but it is not considered an…

Correct answer: Frog
  • A. Lymphocytes
  • B. Blood Plasma
  • C. RBC
  • D. Leucocytes

Explanation: Therefore, the correct answer to the question "Carbonic anhydrase occurs in" is C) RBC (Red Blood Cells).

Correct answer: RBC
  • A. 10000
  • B. 12000
  • C. 15000
  • D. 20000

Explanation: 12,000 stomata per square cm are present on the leaf surface in Tobacco plants.

Correct answer: 12000
  • A. Respiratory exchange
  • B. Breathing
  • C. Diffusion
  • D. Osmosis

Explanation: "The explanation for this question will be added soon!".

Correct answer: Breathing
  • A. Glottis
  • B. Voice-box
  • C. Bronchi
  • D. Both A and B

Explanation: "The explanation for this question will be added soon!".

Correct answer: Both A and B
  • A. Brain
  • B. Heart
  • C. Kidneys
  • D. Lungs

Explanation: "The explanation for this question will be added soon!".

Correct answer: Lungs
  • A. Glottis
  • B. Vocal cords
  • C. Larynx
  • D. Epiglottis

Explanation: "The explanation for this question will be added soon!".

Correct answer: Epiglottis
  • A. Bronchi
  • B. Alveoli
  • C. Terminal bronchiole
  • D. Respiratory bronchiole

Explanation: "The explanation for this question will be added soon!".

Correct answer: Alveoli