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 18 of 23
- A. Parietal pleura
- B. Visceral pleura
- C. Peritoneum pleura
- D. Lung pleura
Explanation: "The explanation for this question will be added soon!".
Correct answer: Visceral pleura- A. Having spongy texture and proper shape
- B. More surface area for diffusion of gases
- C. More space for increasing the volume of inspired air
- D. More nerve supply
Explanation: "The explanation for this question will be added soon!".
Correct answer: More surface area for diffusion of gases- A. Diaphragm
- B. Ribs
- C. Cartilaginous discs
- D. Muscles
Explanation: "The explanation for this question will be added soon!".
Correct answer: Cartilaginous discs- A. Blood from the right side of the heart is carried to the lungs by the pulmonary artery
- B. Pleura are double covering of kidney
- C. Pancreas is both exocrine and endocrine gland
- D. Scurvy is due to a vitamin C deficiency
Explanation: "The explanation for this question will be added soon!".
Correct answer: Pleura are double covering of kidney- A. Plasma
- B. Erythrocytes
- C. Leucocytes
- D. Neurons
Explanation: "The explanation for this question will be added soon!".
Correct answer: Erythrocytes- A. 1,2,3,4,5
- B. 1,3,2,5,4
- C. 5,4,3,1,2
- D. 3,4,5,2,1
Explanation: "The explanation for this question will be added soon!".
Correct answer: 5,4,3,1,2- A. All bronchi
- B. All bronchioles
- C. All bronchi and terminal bronchioles
- D. Alveoli and their ducts
Explanation: "The explanation for this question will be added soon!".
Correct answer: Alveoli and their ducts- A. Alveoli
- B. Bronchi
- C. Bronchioles
- D. Pleura
Explanation: "The explanation for this question will be added soon!".
Correct answer: Alveoli- A. Carboxypeptidase
- B. Succinic dehydrogenase
- C. Carbonic anhydrase
- D. Thrombokinase
Explanation: "The explanation for this question will be added soon!".
Correct answer: Carbonic anhydrase- A. High pO2, high pCO2, high H+ ,high temperature
- B. Low pO2, high pCO2, high H+, high temperature
- C. Low pO2, high pCO2, low H+, low temperature
- D. High pO2, Low pCO2, Low H+, Low temperature
Explanation: "The explanation for this question will be added soon!".
Correct answer: Low pO2, high pCO2, high H+, high temperature- A. Vasopressin and relaxin
- B. Heparin and histamine
- C. Heparin and calcitonin
- D. Serotonin and melanin.
Explanation: Mast cells are the large cells with densely granular cytoplasm that is found in connective tissues.
Correct answer: Heparin and histamine352. Mast cells secrete:
- A. Haemoglobin
- B. Hippurin
- C. Myoglobin
- D. Histamine
Explanation: Mast cells are granulated wandering cells that are found in connective tissue. Their granules contain histamine which is a vasodilator.
Correct answer: Histamine- A. The Eustachian tube and stomach lining
- B. The bronchioles and Fallopian tube
- C. The bile duct and oesophagus
- D. The Fallopian tubes and urethra
Explanation: The ciliated columnar epithelial cells in humans are present in the nasal passages, oviducts (Fallopian tubes) terminal bronchioles…
Correct answer: The bronchioles and Fallopian tube- A. Nasal cavity, larynx, pharynx, trachea, bronchi, alveoli
- B. Nasal cavity, larynx, pharynx, trachea, bronchioles, alveoli
- C. Nasal cavity, pharynx, larynx, trachea, bronchioles, bronchi, alveoli
- D. Nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, alveoli
Explanation: Air passes from nostrils into the nasal cavity where the dust particles are trapped.
Correct answer: Nasal cavity, pharynx, larynx, trachea, bronchi, bronchioles, alveoli- A. Mesophyll
- B. Epidermis
- C. Cortex
- D. Xylem
Explanation: Photosynthesis primarily occurs in the mesophyll tissue of plant leaves.
Correct answer: Mesophyll- A. Carbon dioxide
- B. Oxygen
- C. Dust
- D. Carbon Monoxide
Explanation: Cilia, tiny hair-like structures lining the respiratory passages, play a crucial role in clearing dust and other particulate matter by…
Correct answer: Dust- 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 the lungs, the air in the alveoli is separated from the venous blood in capillaries by the thin squamous epithelium of the alveoli and…
Correct answer: Squamous epithelium + endothelium of blood vessel- 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: Most of the carbon dioxide in the blood is transported to the lungs as bicarbonate ions, formed when CO₂ reacts with water in red blood…
Correct answer: In the form of bicarbonate ions- A. Filtration
- B. pH adjustment
- C. Moistening
- D. Temperature adjustment
Explanation: The nasal cavity does not significantly change the pH of the air we breathe.
Correct answer: pH adjustment- A. Abdominal cavity
- B. Thoracic cavity
- C. Pelvic cavity
- D. Pleural cavity
Explanation: The cavity bounded by the ribs and diaphragm is called the thoracic cavity, or chest cavity.
Correct answer: Thoracic cavity