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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Read the Respiration notesFree MDCAT chapter notes with key terms446 questions · page 13 of 23
241. Goblet cells are:
- A. Unicellular exocrine gland
- B. Unicellular endocrine glands
- C. Multicellular exocrine gland
- D. Multicellular endocrine glands
Explanation: the goblet cells are unicellular exocrine gland. Goblet cells are scattered in the epithelial linings of the intestinal and respiratory…
Correct answer: Unicellular exocrine gland- A. Dorsal
- B. Ventral
- C. Lower part
- D. All of the above
Explanation: In summary, the correct answer is "a) Dorsal." The expiratory center in the medulla is located in the dorsal (back) part of the brainstem.
Correct answer: Dorsal- A. Chloroplasts
- B. Mesophyll
- C. Thylakoids
- D. Stomata
Explanation: Carbon dioxide and oxygen cannot pass through the cuticle, but move in and out of leaves through openings called stomata (stoma = "hole").
Correct answer: Stomata- A. Glottis
- B. Epiglottis
- C. Larynx
- D. Vocal cord
Explanation: Epiglottis is a small, leaf-shaped sheet of elastic cartilage that protects your larynx (voice box) and helps you swallow
Correct answer: Epiglottis- A. Histamine
- B. Heparin
- C. Epinephrine
- D. Antibodies
Explanation: Asthma is a chronic lung disease affecting people of all ages. It is caused by inflammation and muscle tightening around the airways…
Correct answer: Histamine- A. Carboxyhemoglobin
- B. Plasma proteins
- C. Bicarbonate ions
- D. In dissolved form
Explanation: Carbon dioxide can be transported through the blood via three methods. It is dissolved directly in the blood, bound to plasma proteins or…
Correct answer: Bicarbonate ions- A. Inspiratory Reserve Volume
- B. Tidal Volume
- C. Expiratory Reserve Volume
- D. Residual Volume
Explanation: Residual volume is the volume of air which remains in the lungs after the most forceful expiration.
Correct answer: Residual Volume- 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: Reduction in pH of blood causes oxygen haemoglobin dissociation curve to shift to right which indicates dissociation of oxygen from…
Correct answer: Decrease the affinity of haemoglobin with oxygen- A. Inflammation of the trachea
- B. Accumulation of fluid in the lungs
- C. Bacterial infection of the lungs
- D. Allergic reaction of the mast cells in the lungs.
Explanation: Note: The correct option is d) Allergic reaction of the mast cells in the lungs.
Correct answer: Allergic reaction of the mast cells in the lungs.- A. Falling CO2 concentration
- B. Rising CO2 and falling O2 concentration
- C. Falling O2 concentration
- D. Rising CO2 concentration
Explanation: When lungs become concentrated with the same CO2 as in blood, it no longer leaves the blood and keeps rising.
Correct answer: Rising CO2 concentration- A. Have more RBCs and their hemoglobin has a lower binding affinity to O2 .
- B. Are not physically fit to play games like football.
- C. Suffer from altitude sickness with symptoms like nausea, fatigue, etc.
- D. Have the usual RBC count but their haemoglobin has a very high binding affinity to O 2.
Explanation: After about six months at high altitude the body acclimatises: it produces more red blood cells (polycythaemia) and raises 2,3-BPG, which…
Correct answer: Have more RBCs and their hemoglobin has a lower binding affinity to O2 .- A. Attached to haemoglobin
- B. Dissolved in the blood
- C. As Bicarbonates
- D. As Carbonates
Explanation: When systemic arterial blood flows through capillaries, carbon dioxide diffuses from the tissues into the blood.
Correct answer: As Bicarbonates- A. Carbohydrate
- B. Respiratory pigment
- C. Vitamin
- D. Skin pigment
Explanation: Haemoglobin (Hb) is a conjugated protein. It consists of a basic protein globin joined to a nonprotein group heme.
Correct answer: Respiratory pigment- A. passive transport
- B. active transport
- C. osmosis
- D. diffusion.
Explanation: (d) : Diffusion is the net flow of a substance from a region of higher concentration to a region of lower concentration.
Correct answer: diffusion.- A. 3.34%
- B. 4%
- C. 0.0314%
- D. 0.34%.
Explanation: (c) : The atmosphere (air) is a mixture of several gases. Near the earth's surface it consists of 78% nitrogen, 21% oxygen, 0.93% argon…
Correct answer: 0.0314%- A. Transitional epithelium + Tunica externa of blood vessel
- B. Squamous epithelium + Endothelium of blood vessel
- C. Squamous epithelium + Tunica media of blood vessel
- D. None of the above
Explanation: In lungs, the air is separated from the venous blood through squamous epithelium and endothelium of blood vessel.
Correct answer: Squamous epithelium + Endothelium of blood vessel- A. Residual volume
- B. Inspiratory reserve volume
- C. Vital capacity
- D. Tidal volume.
Explanation: All options are explained below: a)Residual volume (Correct Option): Residual volume is the volume of air that remains in the lungs even…
Correct answer: Residual volume- A. Periosteum
- B. Perichondrium
- C. Pericardium
- D. Pleural membrane
Explanation: All options are explained below: a)Periosteum: Periosteum is a dense layer of vascular connective tissue that covers the surface of bones.
Correct answer: Pleural membrane- A. Non-ciliated columnar
- B. Non-ciliated squamous
- C. Ciliated columnar
- D. Ciliated squamous
Explanation: (b) : In the lung, each alveolar duct opens into a blind chamber, the alveolar sac, or infundibulum.
Correct answer: Non-ciliated squamous- A. Active Transport
- B. Osmosis
- C. Diffusion
- D. Active Transport and Diffusion
Explanation: In animals, oxygen and carbon dioxide move by diffusion across moist membranes.
Correct answer: Diffusion