Question

18 chemosynthesis is a cellular process used by organisms in deep sea ecosystems in the absence of light. a chemical equation for chemosynthesis is shown. chemosynthesis equation $ h _ { 2 } s + co _ { 2 } + h _ { 2 } o
ightarrow c _ { 6 } h _ { 12 } o _ { 6 } + h _ { 2 } so _ { 4 } $ how is chemosynthesis different from photosynthesis? a chemosynthesis harvests energy from other chemical compounds. b chemosynthesis requires carbon dioxide. c chemosynthesis produces energy in the form of sugars. d chemosynthesis is used by autotrophic organisms.

Explanation:

• Photosynthesis: Uses light energy (\(sunlight\)) to convert \(CO_2\) and \(H_2O\) into glucose (\(C_6H_{12}O_6\)) and \(O_2\). The general equation is \(6CO_2 + 6H_2O\xrightarrow{light}C_6H_{12}O_6+6O_2\).
• Chemosynthesis: As the problem states, it occurs in the absence of light. It harvests energy from chemical compounds (in the given equation, \(H_2S\) is likely the energy - rich chemical compound).
• Option B: Both photosynthesis (\(6CO_2 + 6H_2O\xrightarrow{light}C_6H_{12}O_6+6O_2\)) and chemosynthesis (\(H_2S + CO_2+H_2O

ightarrow C_6H_{12}O_6 + H_2SO_4\)) require \(CO_2\), so this is not a difference.

• Option C: Both photosynthesis and chemosynthesis produce energy in the form of sugars (\(C_6H_{12}O_6\) is a sugar in both processes), so this is not a difference.
• Option D: Both photosynthetic (e.g., plants) and chemosynthetic (e.g., some bacteria) organisms are autotrophic (they produce their own food), so this is not a difference.

Answer:

A. Chemosynthesis harvests energy from other chemical compounds.