F2 IS WS08 Answers

1st Term WS 08 Submission date：_____________ Name：______________________ Class & no.：2 _________(     )

7.4       How do green plants obtain energy?

B. How do we know whether photosynthesis has occurred?

C. The necessary conditions for photosynthesis

i      Words to know:

	English term	Write the words again	Chinese term
1	Starch		澱粉
2	Iodine solution		碘液
3	Iodine test		碘液試驗
4	Necessary		必須
5	Destarching		脫澱粉
6	Soda lime		鹼石灰

i      Fill in the blanks:

1             The test using iodine solution is called the iodine test. In this test, a colour change from

brown to dark blue shows the presence of starch.

2        Light energy is required in photosynthesis. It is absorbed by chlorophyll

in green leaves and other green parts of the plants.

3        The food produced is usually stored in the form of starch. And oxygen is produced as a

by-product that released into the air.

4        Carbon dioxide, chlorophyll, light and water are necessary for photosynthesis to take place.

5       Destarching is the process of removing starch from the leaves by putting the plant in the dark for one or two days.

6       soda lime is a chemical that can absorb carbon dioxide.

i      Concept checking:

Decide whether the following statements are true or false, and try to rewrite the true statements.

1        Carbon dioxide, water, and chlorophyll are the raw materials of photosynthesis.               True / False

Carbon dioxide and water are the raw materials of photosynthesis.

2        Soda lime can be used to supply carbon dioxide.                                                              True / False

Soda lime can be used to absorb carbon dioxide.

3        Carbon dioxide, water and chlorophyll are necessary for photosynthesis to take place.        True / False

(Any one of them is necessary)

4.       We can destarch the leaves of a plant by keeping it in the dark for one or two hours.        True / False

We can destarch the leaves of a plant by keepting in the dark for one to two days.