Identifying Condiptions Needed For Photosynthesis

Question 1

How can we test a plant to show it needs chlorophyll for photosynthesis?

Answer 1

We use a variegated leaf and test it for the presence of starch

Question 2

What result do you get from the green part of the leaf this experiment?

Answer 2

The green parts containing chlorophyll will be stained a blue-black colour because starch is present

Question 3

What result do you get from the light parts of the leaf in this experiment?

Answer 3

The light parts that don’t contain chlorophyll won’t change and the iodine will stay orange because there is no starch present

Question 4

Testing a leaf for starch can be used to show how photosynthesis is affected by what 3 things?

Answer 4

~The presence of chlorophyll in the cells of a leaf
~Light reaching a leaf
~Carbon dioxide in the atmosphere around a leaf

Question 5

What can we show that carbon dioxide is needed for photosynthesis?

Answer 5

We deprive a plant of carbon dioxide and the. Test it for the presence of starch

Question 6

What result do we get from the bell jar containing sodium bicarbonate? (Plenty of carbon dioxide)

Answer 6

It is stained blue-black showing that starch is present

Question 7

What result do we get from the bell jar containing sodium hydroxide? (No carbon dioxide)

Answer 7

The iodine remains orange because no starch is present

Question 8

What are the 4 uses of glucose during photosynthesis?

Answer 8

~It is used to release energy in respiration
~It can be change into starch and stored
~It can be used to make cellulose which make up the body of plants
~It can be used to make proteins