Question

which of the following are differences between photosynthesis and cellular respiration?
select all that apply
a photosynthesis and cellular respiration use the same sequence of chemical reactions.
b photosynthesis uses sunlight as an energy source, while cellular respiration uses glucose.
c both processes occur only during the day.
d photosynthesis produces glucose and oxygen, while cellular respiration produces carbon dioxide and water.
e photosynthesis occurs in the chloroplasts, while cellular respiration occurs in the mitochondria.

Explanation:

• Option a: Photosynthesis and cellular respiration have different chemical reaction sequences. Photosynthesis is \(6CO_2 + 6H_2O+light

ightarrow C_6H_{12}O_6 + 6O_2\), while cellular respiration (aerobic) is \(C_6H_{12}O_6+6O_2
ightarrow 6CO_2 + 6H_2O+energy\). So, this option is incorrect.

• Option b: Photosynthesis uses sunlight as an energy source (light - dependent reactions) to convert \(CO_2\) and \(H_2O\) into glucose. Cellular respiration breaks down glucose (and other organic molecules) to release energy. This is a valid difference.
• Option c: Photosynthesis occurs during the day (when there is light). Cellular respiration occurs all the time (day and night) in most living cells. So, this option is incorrect.
• Option d: Photosynthesis products are glucose (\(C_6H_{12}O_6\)) and oxygen (\(O_2\)). Aerobic cellular respiration products are carbon dioxide (\(CO_2\)) and water (\(H_2O\)). This is a valid difference.
• Option e: Photosynthesis occurs in chloroplasts (in plant cells and some protists). Aerobic cellular respiration (the later stages - citric acid cycle and oxidative phosphorylation) occurs in mitochondria. This is a valid difference.

Answer:

B. Photosynthesis uses sunlight as an energy source, while cellular respiration uses glucose.
D. Photosynthesis produces glucose and oxygen, while cellular respiration produces carbon dioxide and water.
E. Photosynthesis occurs in the chloroplasts, while cellular respiration occurs in the mitochondria.