Respiration is an involuntary process in _ way.

A. When voluntary respiration is not possible

What regulates the rate of breathing in humans?

D. Hydrogen ion concentration in muscles

Everyday Science · Body Systems (Human Biology) · page 4 of 12

Respiratory System MCQs with Answers

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Respiratory System MCQs (31–40)

10 MCQs with answers and a short one-liner. Hide answers to test yourself.

Past paper MCQs in this chapter · See all past papers

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31.
Respiration is an involuntary process in _ way.
Correct Answer: A. When voluntary respiration is not possible
One-liner
Respiration is an involuntary process in when voluntary respiration is not possible way.
32.
During the breathing process diaphragm plays a key role, where does diaphragm move during exhalation?
Correct Answer: D. Move upwards
One-liner
During exhalation, the diaphragm moves upwards as it relaxes, reducing the chest cavity volume and pushing air out of the lungs.
33.
How many lobes are present in the right lung?
Correct Answer: B. 3
One-liner
The right lung has 3 lobes, while the left lung has only 2 lobes to accommodate the heart.
34.
What regulates the rate of breathing in humans?
Correct Answer: B. Carbon dioxide in blood
One-liner
The rate of breathing in humans is primarily regulated by the concentration of carbon dioxide in blood.
35.
The Diaphragm in human body assists in _?
Correct Answer: D. Respiration
One-liner
The diaphragm is a dome-shaped muscle that assists in respiration by contracting and relaxing to help the lungs inhale and exhale air.
36.
Chemicals in tobacco smoke lead to the breakdown of the elastic tissue in the walls of the alveoli. What is the name of this condition?
Correct Answer: B. Emphysema
One-liner
The breakdown of elastic tissue in alveolar walls due to tobacco smoke chemicals is called Emphysema.
37.
What do we breathe in to stay alive?
Correct Answer: C. Oxygen
One-liner
We breathe in oxygen to stay alive.
38.
Past Paper MCQ
How many times does a normal man respire per minute?
Correct Answer: B. 14–18 times
One-liner
A normal adult man respires 14–18 times per minute at rest.
39.
The alveoli is lined by?
Correct Answer: B. Squamous epithelium
One-liner
The alveoli are lined by squamous epithelium, which is a thin, flat layer of cells that facilitates efficient gas exchange.
40.
What is the main source of human breathing?
Correct Answer: D. Lungs
One-liner
The main source of human breathing is the lungs, which are the primary organs of the respiratory system responsible for gas exchange.

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Respiratory System MCQs with Answers

Respiratory System MCQs (31–40)

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