F2 1st Term IS WS 08 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	Starch	澱粉
2	Iodine solution/ test	Iodine solution / test	碘液 / 碘液試驗
3	Necessary	Necessary	必須的
4	Destarching	Destarching	脫澱粉
5	Sodium hydrogencarbonate solution	Sodium hydrogencarbonate solution	碳酸氫鈉溶液
6	Soda lime	Soda lime	鹼石灰

i      Matching:

Alcohol			removes chlorophyll from the leaf.
Destarching			removes starch from the leaves by putting the plant in the dark for one or two days.
Iodine solution			is used to test for the presence of starch.
Soda lime			absorbs carbon dioxide in air.
Sodium hydrogencarbonate solution			can provide carbon dioxide to water plant.
Starch			is a form of food stored in green plants.

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        Alcohol is used to remove the chlorophyll from the leaf.

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

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

5        Sodium hydrogencarbonate solution can provide carbon dioxide to water plants.

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

Sodium hydrogencarbonate solution can be used to supply carbon dioxide /

Soda lime can be used to absorbe carbon dioxide.

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

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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 keeping it in the dark for one or two days.