+20 Questions on Chemosynthesis
20 multiple choice questions on Chemosynthesis, numbered with the answer key at the end.
Multiple Choice Questions: Chemosynthesis
1. What is chemosynthesis?
A) The process of producing food using sunlight
B) The process of producing food using chemical energy
C) The breakdown of food molecules
D) The release of energy from glucose
2. Which organisms primarily perform chemosynthesis?
A) Plants
B) Animals
C) Certain bacteria and archaea
D) Fungi
3. Where is chemosynthesis most commonly found?
A) Surface of leaves
B) Hydrothermal vents in the deep ocean
C) Desert soils
D) Freshwater lakes
4. What is the primary energy source for chemosynthesis?
A) Sunlight
B) Heat
C) Inorganic chemical compounds
D) Glucose
5. Which compound is often oxidized in chemosynthesis to provide energy?
A) Carbon dioxide
B) Hydrogen sulfide
C) Oxygen
D) Nitrogen
6. What gas is fixed into organic molecules during chemosynthesis?
A) Oxygen
B) Nitrogen
C) Carbon dioxide
D) Methane
7. Chemosynthesis is most similar to which process?
A) Fermentation
B) Photosynthesis
C) Respiration
D) Digestion
8. Which of these is NOT involved in chemosynthesis?
A) Light energy
B) Carbon dioxide
C) Inorganic molecules
D) Chemical oxidation
9. What is the general equation for chemosynthesis involving hydrogen sulfide?
A) CO₂ + O₂ + H₂S → C₆H₁₂O₆ + S + H₂O
B) CO₂ + H₂O → C₆H₁₂O₆ + O₂
C) C₆H₁₂O₆ + O₂ → CO₂ + H₂O
D) CO₂ + CH₄ → C₆H₁₂O₆ + H₂O
10. Which environment is least likely to have chemosynthetic organisms?
A) Deep sea vents
B) Hot springs
C) Forest floor
D) Ocean floor sediments
11. What type of organisms rely directly on chemosynthetic bacteria for food?
A) Herbivores
B) Carnivores
C) Primary consumers near vents
D) Decomposers
12. What is the importance of chemosynthesis in deep-sea ecosystems?
A) It produces oxygen for marine life
B) It forms the base of the food chain where sunlight is absent
C) It breaks down dead organisms
D) It supplies nitrogen to plants
13. Which molecule is commonly produced as a byproduct in chemosynthesis involving sulfur?
A) Oxygen
B) Sulfur or sulfate
C) Methane
D) Nitrogen
14. Chemosynthetic bacteria are classified as:
A) Autotrophs
B) Heterotrophs
C) Parasites
D) Saprophytes
15. Which of the following best describes the energy source for photosynthesis versus chemosynthesis?
A) Both use sunlight
B) Photosynthesis uses chemical energy, chemosynthesis uses light
C) Photosynthesis uses sunlight, chemosynthesis uses chemical energy
D) Both use chemical energy
16. In chemosynthesis, carbon dioxide is converted into:
A) Oxygen
B) Organic molecules such as glucose
C) Water
D) Inorganic salts
17. Which of the following chemicals is NOT typically used as an energy source in chemosynthesis?
A) Hydrogen sulfide
B) Ammonia
C) Methane
D) Glucose
18. What is the role of oxidizing agents in chemosynthesis?
A) To provide electrons for chemical reactions
B) To absorb sunlight
C) To break down glucose
D) To store energy as ATP
19. Chemosynthesis is essential for ecosystems where:
A) There is abundant sunlight
B) There is no oxygen
C) There is little or no sunlight
D) Only plants grow
20. Which statement about chemosynthesis is true?
A) It can only occur in the presence of sunlight
B) It produces energy-rich organic compounds without light
C) It is a form of cellular respiration
D) It releases energy by breaking down glucose
Answer Key
1. B – The process of producing food using chemical energy
2. C – Certain bacteria and archaea
3. B – Hydrothermal vents in the deep ocean
4. C – Inorganic chemical compounds
5. B – Hydrogen sulfide
6. C – Carbon dioxide
7. B – Photosynthesis
8. A – Light energy
9. A – CO₂ + O₂ + H₂S → C₆H₁₂O₆ + S + H₂O
10. C – Forest floor
11. C – Primary consumers near vents
12. B – It forms the base of the food chain where sunlight is absent
13. B – Sulfur or sulfate
14. A – Autotrophs
15. C – Photosynthesis uses sunlight, chemosynthesis uses chemical energy
16. B – Organic molecules such as glucose
17. D – Glucose
18. A – To provide electrons for chemical reactions
19. C – There is little or no sunlight
20. B – It produces energy-rich organic compounds without light
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