Question

activity c (continued from previous page)

1. review: in photosynthesis and respiration, energy is converted from one form to another. light is a form of radiant energy. glucose and atp molecules store chemical energy.

a. during photosynthesis, what role is played by the radiant energy of the sun? explain your answer.

b. in photosynthesis, what form of energy is sunlight converted to, and how is this energy stored?

c. does cellular respiration result in a net input of energy or a net output of energy? explain.

d. how is the energy produced by respiration stored?

1. summarize: how are respiration and photosynthesis related to each other?

1. think and discuss: in what ways are plants and animals dependent on each other?

Explanation:

A. The radiant energy of the Sun is used as the energy source for photosynthesis. It powers the conversion of carbon dioxide and water into glucose and oxygen.
B. Sunlight is converted to chemical energy. This energy is stored in the bonds of glucose molecules.
C. Cellular respiration results in a net output of energy. Glucose is broken down, and energy is released (along with carbon dioxide and water).
D. The energy produced by respiration is stored in ATP (adenosine triphosphate) molecules.

1. Photosynthesis produces glucose and oxygen. Cellular respiration uses glucose and oxygen to produce carbon dioxide and water (which are then used in photosynthesis).
2. Plants produce oxygen (via photosynthesis) that animals need for respiration. Animals produce carbon dioxide (via respiration) that plants need for photosynthesis. Also, some animals eat plants (for food - glucose), and some plants rely on animals for pollination or seed dispersal.

Answer:

A. The Sun's radiant energy is the energy source for photosynthesis.
B. Sunlight is converted to chemical energy and stored in glucose.
C. Net output of energy; glucose breakdown releases energy.
D. Stored in ATP.

1. Photosynthesis and respiration are complementary (products of one are reactants of the other).
2. Plants provide oxygen (and food for some), animals provide carbon dioxide (and assist in plant reproduction/spread).