Free Respiration MCQs with Answers
446 Respiration MCQs from Biology, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
The human respiratory system includes the air passages, lungs, alveoli and breathing muscles, while gaseous exchange explains how oxygen enters blood and carbon dioxide leaves it by diffusion. The effects of smoking include damage to cilia and alveoli, reduced gas exchange, chronic bronchitis, emphysema and increased risk of lung cancer.
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261. Goblets cells are:
- A. Unicellular exocrine gland
- B. Unicellular endocrine glands
- C. Multicellular exocrine gland
- D. Multicellular endocrine glands
Explanation: The most common unicellular exocrine glands are the goblet cells (mucus secreting cells) found in the epithelium of the trachea and the…
Correct answer: Unicellular exocrine gland- A. Kidneys
- B. Brain
- C. Lungs
- D. Nasal passage
Explanation: "The explanation for this question will be added soon!".
Correct answer: Lungs- A. Removal of foreign particles from incoming air.
- B. Humidifies incoming air
- C. Bring the temperature of incoming air to body temperature.
- D. All the above
Explanation: "The explanation for this question will be added soon!".
Correct answer: All the above- A. Bony rings
- B. Chitinous rings
- C. Turgid pressure
- D. Cartilaginous rings
Explanation: "The explanation for this question will be added soon!".
Correct answer: Cartilaginous rings- A. Equal to that in the blood
- B. More than that in the blood
- C. Less than that in the blood
- D. Less than that of carbon dioxide.
Explanation: The correct option is b) More than that in the blood. Explanation of each option: a) Equal to that in the blood: This option suggests that…
Correct answer: More than that in the blood- A. There is a negative pressure in the lungs
- B. There is a negative intarpleural pressure pulling at the lung walls
- C. There is a positive intrapleural pressure
- D. Pressure in the lungs is higher than the atmospheric pressure.
Explanation: Option B is correct. All options are explained below:a)There is a negative pressure in the lungs": This statement is not entirely…
Correct answer: There is a negative intarpleural pressure pulling at the lung walls- A. Decrease the affinity of haemoglobin with oxygen
- B. Release bicarbonate ions by the liver
- C. Reduce the rate of heart beat
- D. Reduce the blood supply to the brain.
Explanation: The correct option is "a". All options are explained below: a)"Decrease the affinity of hemoglobin with oxygen": This statement is…
Correct answer: Decrease the affinity of haemoglobin with oxygen- A. Respiratory acidosis
- B. Respiratory alkalosis
- C. Emphysema
- D. Asthma
Explanation: The correct option is c) Emphysema. Explanation of each option: a)"Respiratory acidosis": Respiratory acidosis is not a chronic…
Correct answer: Emphysema- A. Pneumonia
- B. Asthma
- C. Pleurisy
- D. Emphysema
Explanation: Note: The correct option is d) Emphysema. Explanation of each option: a)Pneumonia: Pneumonia is an inflammatory lung condition primarily…
Correct answer: Emphysema- A. Cigarette smoking may lead to inflammation of bronchi
- B. Neural signals from pneumotoxic centre in pons region of brain can increase the duration of inspiration
- C. Asthma is a condition in which your airways narrow and swell and may produce extra mucus
- D. About 90% of carbon dioxide (CO2) is carried by haemoglobin as carbamino haemoglobin
Explanation: All options are explained below: a)Cigarette smoking may lead to inflammation of bronchi: Cigarette smoking is a well-known risk factor…
Correct answer: Asthma is a condition in which your airways narrow and swell and may produce extra mucus- A. Acts as a reserve during muscular exercise
- B. Raises the pCO2 of blood to 75 mm of Hg.
- C. Is enough to keep oxyhaemoglobin saturation at 96%
- D. Helps in releasing more O2 to the epithelial tissues.
Explanation: Option A is correct. All options are explained below: a)Acts as a reserve during muscular exercise (Correct Option):This statement is…
Correct answer: Acts as a reserve during muscular exercise- A. One can conciously breathe in and breathe out by moving the diaphragm alone, without moving the ribs at all.
- B. The lungs can be made fully empty by forcefully breathing out all air from them.
- C. One can breathe out air totally without residual air.
- D. One can breathe out air through Eustachian tubes by closing both the nose and the mouth.
Explanation: Correct option is A)a)One can consciously breathe in and breathe out by moving the diaphragm alone, without moving the ribs at all: This…
Correct answer: One can conciously breathe in and breathe out by moving the diaphragm alone, without moving the ribs at all.- A. Bicarbonate in blood plasma and RBCs
- B. Free CO2 in blood plasma
- C. 70% carbaminohaemoglobin and 30% as bicarbonate
- D. Carbaminohaemoglobin in RBCs
Explanation: All options are explained below: a)Bicarbonate in blood plasma and RBCs (Correct Option):The bulk of carbon dioxide (CO2) released from…
Correct answer: Bicarbonate in blood plasma and RBCs- A. (ii) 2500 mL, (iii) 4500 mL
- B. (iii) 1200 mL, (iv) 2500 mL
- C. (iv) 3500 mL, (i) 1200 mL
- D. (i) 4500 mL, (ii) 3500 mL
Explanation: All options are explained below: a)(ii) 2500 mL, (iii) 4500 mL:This option pairs capacity (ii) with 2500 mL and capacity (iii) with 4500…
Correct answer: (iv) 3500 mL, (i) 1200 mL- A. They carry about 20-25 percent of CO2
- B. They transport 99.5 percent of O2
- C. They transport about 80 percent oxygen only and the rest 20 percent of it is transported in dissolved state in blood plasma
- D. They do not carry CO2 at all.
Explanation: All options are explained below: a)They carry about 20-25 percent of CO2 (Correct Option): Red blood cells (RBCs) play a significant role…
Correct answer: They carry about 20-25 percent of CO2- A. Inspiratory reserve volume plus expiratory reserve volume
- B. Total lung capacity minus residual volume
- C. Inspiratory reserve volume plus tidal volume
- D. Total lung capacity minus expiratory reserve volume
Explanation: All options are explained below: A. Inspiratory reserve volume plus expiratory reserve volume:The vital capacity of the lungs is…
Correct answer: Total lung capacity minus residual volume- A. has only 2 protein subunits instead of 4
- B. has a higher affinity for oxygen that that of an adult
- C. has a lower affinity for oxygen than that of the adult
- D. its affinity for oxygen is the same as that of an adult.
Explanation: A. The hemoglobin of a human fetus has only 2 protein subunits instead of 4: This statement is not accurate.
Correct answer: has a higher affinity for oxygen that that of an adult- 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.