Chapter 3 Section 3 Photosynthesis

Question 1

1. Why do living things need energy?

Answer 1

• All living things need energy to carry out life’s functions (cell’s functions)

Question 2

2. What is photosynthesis?

Answer 2

• The process by which a cell captures energy in sunlight and uses it to make food

Question 3

3. Organisms that make their own food is called an

Answer 3

autotroph

Question 4

4. An organism that cannot make their own food is called a

Answer 4

heterotroph

Question 5

5. What are the 2 stages of photosynthesis?

Answer 5

Stage 1:

1. Chloroplasts captures sunlight
2. Chlorophyll absorbs the sunlight

Stage 2:

1. Roots absorb water
2. Stomata take in Carbon dioxide
3. Water and Carbon dioxide meet in the chloroplast and undergo chemical reactions powered by the energy captured in the first stage.
4. These chemical reactions produce oxygen and glucose
5. The oxygen exits through the stomata and the glucose is used to carry out cell functions

Question 6

6. What is the energy captured in the first stage used for?

Answer 6

• To power the second stage of photosynthesis

Question 7

7. What pigment in chloroplasts absorbs light?________

Answer 7

chlorophyll

Question 8

8. How are roots and stomata important for photosynthesis?

Answer 8

• Roots absorb water and stomata take in carbon dioxide which is important for photosynthesis

Question 9

9. What role do you think the guard cells play?

Answer 9

• They regulate what goes in and out of the stomata.

Question 10

10. When do you think the stomata are usually open?

Answer 10

• Daytime because there is sunlight during the day when light energy is available for photosynthesis

Question 11

11. What is the equation for photosynthesis?

Answer 11

6CO2 + 6 H2O light energy> C6H12O6 + 6O2

Question 12

12. Would you expect a plant to produce more oxygen on a cloudy day or a sunny day? Explain.

Answer 12

• Sunny day because there is sunlight that provides energy for photosynthesis

Question 13

13. An insect eats a leaf. Explain how the insect depends on the sun for energy.

Answer 13

• The leaf has stored food in the mitochondria that the plant made using energy from the sun in the process of photosynthesis.

Question 14

14. When you eat food from plants you are eating the plant’s _________.

Answer 14

stored energy