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 7 of 23
- A. Asthma
- B. Sinusitis
- C. Bronchitis
- D. Pneumonia
Explanation: The key terms in the question are 'bubbling sounds' and 'fluid in the alveoli.' These are characteristic of pneumonia, a condition where…
Correct answer: Pneumonia- A. Pharynx and larynx
- B. Pharynx and trachea
- C. Trachea and Bronchus
- D. Larynx and bronchioles
Explanation: The pharynx is lined by ciliated pseudostratified columnar epithelium and nonkeratinized stratified squamous epithelium depending on…
Correct answer: Trachea and Bronchus- A. Pulmonary respiration in frogs
- B. Tracheal respiration in cockroach
- C. Cutaneous respiration in earthworms
- D. Bucco-pharyngeal respiration in frogs
Explanation: Tracheal respiration in cockroaches involves a system of air-filled tubes called tracheae that deliver oxygen directly to cells, bypassing…
Correct answer: Tracheal respiration in cockroach- A. I only
- B. I and II
- C. III only
- D. II and III
Explanation: III represents bronchioles, which lack cartilage. Both I (trachea) and II (bronchi) have cartilage.
Correct answer: III only- A. Trachea
- B. Bronchi
- C. Nasal cavity
- D. Alveolar space
Explanation: The correct answer is the nasal cavity. The nasal cavity is lined with mucous membranes and has a rich blood supply which helps to warm…
Correct answer: Nasal cavity- A. Compression of the rib cage
- B. Outward movement of ribs
- C. Inward movement of sternum
- D. Relaxation of the diaphragm muscles
Explanation: The contraction of the external intercostal muscles during inhalation causes the ribs to move outward and upward.
Correct answer: Outward movement of ribs- A. Both pressure and volume increase
- B. Pressure increases, volume decreases
- C. Pressure decreases, volume increases
- D. Both pressure and volume decrease
Explanation: During inhalation, the diaphragm contracts and moves downward, and the intercostal muscles contract, expanding the rib cage.
Correct answer: Pressure decreases, volume increases- A. Tuberculosis
- B. Emphysema
- C. Lung cancer
- D. Pneumonia
Explanation: The correct answer is Tuberculosis. Tuberculosis (TB) is a chronic bacterial infection caused by Mycobacterium tuberculosis, which can…
Correct answer: Tuberculosis- A. A
- B. B
- C. C
- D. D
Explanation: During exhalation in humans, the diaphragm relaxes, causing it to move upwards into the thoracic cavity.
Correct answer: D- A. Pelvis
- B. Hilum
- C. Mediastinum
- D. Fissure
Explanation: The hilum of the lung is found on the medial aspect of each lung, and it is the only site of entrance or exit of structures associated…
Correct answer: Hilum- A. Glottis
- B. Bronchus
- C. Larynx
- D. Trachea
- E. Pleura
Explanation: The vocal cords are two thin, fibrous bands located in the larynx or voice box, which is a part of the respiratory system.
Correct answer: Larynx- A. Spirobacterium
- B. Mycobacterium
- C. E.Coli
- D. Staphylococcus
- E. Pseudomonas
Explanation: Tuberculosis (TB) is caused by the bacterium Mycobacterium tuberculosis, which is highly infectious and can spread through the air.
Correct answer: Mycobacterium- A. 15
- B. 19
- C. 19.6
- D. 20
- E. 25
Explanation: At sea level, hemoglobin can carry a maximum of approximately 20 ml of oxygen per 100 ml of blood.
Correct answer: 20- A. Oxyhemoglobin
- B. Plasmin
- C. Myoglobin
- D. Heme
- E. Hemoglobin
Explanation: Myoglobin is a protein found in muscle tissue that binds oxygen.
Correct answer: Myoglobin- A. 1
- B. 4
- C. 3
- D. 2
- E. 5
Explanation: Hemoglobin is a protein found in red blood cells that has four heme groups, each capable of binding to one oxygen molecule.
Correct answer: 4- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation: It is a fact that bronchioles don't have cartilage, so options A and C are incorrect.
Correct answer: Option D- A. Pleura
- B. Alveoli
- C. Chest cage
- D. Diaphragm
Explanation: Diaphragm forms the floor of the chest cavity.
Correct answer: Diaphragm- A. Lung cancer
- B. Chronic Bronchitis
- C. Cystic fibrosis
- D. Emphysema
Explanation: Cystic fibrosis (CF) is a genetic (inherited) disease that causes sticky, thick mucus to build up in organs, including the lungs and the…
Correct answer: Cystic fibrosis- A. 10 to 15 times per minute
- B. 10 to 20 times per minute
- C. 80 to 120 times per minute
- D. 15 to 20 times per minute
Explanation: Correct option is D. Normal respiration rates for an adult person at rest is 15 to 20 breaths per minute.
Correct answer: 15 to 20 times per minute- A. Heart
- B. Lungs
- C. Brain
- D. Kidney
Explanation: The pleural membranes cover the lungs and have a pleural fluid in between them to lubricate the lungs and prevent damage due to friction.
Correct answer: Lungs