MCQ Questions for Class 7 Science: Ch 10 Respiration in Organisms
1. Chest cavity is surrounded by
(a) 12 pair of ribs
(b) 10 pair of ribs
(c) 11 pair of ribs
(d) 25 ribs
► (a) 12 pair of ribs
2. Oxidation of food inside cell takes place in
(a) Golgi bodies
(b) Mitochondria
(c) Chromosome
(d) Ribosome
► (b) Mitochondria
3. The chemical used to test the carbon dioxide gas in exhaled air is
(a) Lime water
(b) Lime stone
(c) Lime juice
(d) Quick lime
► (a) Lime water
4. Lime water turns milky due to the presence of which of the following gases?
(a) Carbon monoxide
(b) Carbon dioxide
(c) Nitrogen
(d) Oxygen
► (b) Carbon dioxide
5. What is the function of the hair in the nose?
(a) To secrete mucus.
(b) To trap dust particles.
(c) To protect the mucus glands.
(d) To prevent germs from entering the lungs.
► (b) To trap dust particles.
6. Haemoglobin carries oxygen molecules as
(a) Carboxy-pigement.
(b) Carboxyhaemoglobin
(c) Oxyhaemoglobin
(d) Chloroplast
► (c) Oxyhaemoglobin
7. Plants breathe through their stomata located in their
(a) Leaves
(b) Stem
(c) Flowers
(d) Roots
► (a) Leaves
8. More energy is released in
(a) Breathing
(b) Fermentation
(c) Anaerobic respiration
(d) Aerobic respiration
► (d) Aerobic respiration
9. Why do we get, muscle cramps after heavy exercise?
(a) It is due to the partial breakdown of glucose to produce lactic acid.
(b) It is due to the complete breakdown of glucose to produce lactic acid.
(c) It is due to the muscle cells that respire in the presence of oxygen.
(d) It is due to the increased supply of oxygen to muscle cells.
► (a) It is due to the partial breakdown of glucose to produce lactic acid.
10. Voice box is present in
(a) Pharynx
(b) Epiglottis
(c) Mouth
(d) Larynx
► (d) Larynx
11. Breathing is a
(a) Biochemical process
(b) Biological process
(c) Chemical process
(d) Physical process
► (d) Physical process
12. Which of the following statements is correct for anaerobic respiration?
(a) Food is broken down in the absence of oxygen to release energy.
(b) Breakdown of food occurs in presence of oxygen.
(c) It is a slow process compared to aerobic respiration.
(d) It produces large amount of energy compared to aerobic respiration.
► (a) Food is broken down in the absence of oxygen to release energy.
13. Muscular floor of the chest cavity is called
(a) Rib cage
(b) Diaphragm
(c) Trachea
(d) Bronchus
► (b) Diaphragm
14. Small thin walled balloon like structure that help in exchange of gases are
(a) Arteries
(b) Veins
(c) Stomata
(d) Alveoli
► (d) Alveoli
15. Instant source of energy is
(a) Sugar
(b) Fat
(c) Vitamins
(d) Glucose
► (d) Glucose
16. Stomata are surrounded by
(a) Pigmented cells
(b) Accessories cells
(c) Guard cells
(d) Lenticels
► (c) Guard cells
17. The minute pores present on the surface of leaves are called
(a) Stomata
(b) Mesophyll cells
(c) Lenticels
(d) Guard cells
► (a) Stomata
18. Which of these are the organs of human respiratory system?
(a) Trachea
(b) Bronchus
(c) Alveolus
(d) All of these
► (d) All of these
19. Breathing involves inspiration and expiration process. Which of the following take place during inspiration?
(a) Ribs move downward and outward.
(b) Ribs move upward and inward.
(c) Ribs move downward and inward.
(d) Ribs move upward and outward.
► (d) Ribs move upward and outward.
20. The opening of the pharynx to larynx is guarded by
(a) Adam’s apple
(b) Epiglottis
(c) Alveoli
(d) Trachea
► (b) Epiglottis
21. What is the end product of glucose in the abscence of oxygen in muscle cells?
(a) Carbon dioxide
(b) Lactic acid
(c) Ethanol
(d) Water
► (b) Lactic acid
22. Which statement is correct?
(a) Exhaled air contains more oxygen and less carbon dioxide.
(b) Exhaled air contains less oxygen and less carbon dioxide.
(c) Inhaled air contains equal amount of carbon dioxide and oxygen.
(d) Exhaled air contains more carbon dioxide and less oxygen.
► (d) Exhaled air contains more carbon dioxide and less oxygen.
23. In insects, air enters the body through
(a) Spiracles
(b) Gills
(c) Lungs
(d) Skin
► (a) Spiracles
24. On an average, adult human being during rest breaths ___________ times in a minute.
(a) 41562
(b) 70-72
(c) 20-25
(d) 15-18
► (d) 15-18
25. Inhalation is the
(a) Release of oxygen
(b) Intake of carbon dioxide
(c) Intake of oxygen
(d) Release of carbon dioxide
► (c) Intake of oxygen
26. Air tubes in insect is called
(a) Gills
(b) Air tube
(c) Air bladder
(d) Tracheae
► (d) Tracheae