"The actual Unit 3."

Question 1

Four steps to test for starch:

Plus, how you know there is starch.

Answer 1

1. Get a beaker of boiling water and put a leaf in it for 3 minutes.
2. Place leaf in a test tube with ethanol in it, and put in the boiling beaker for 3 minutes.
3. Wash in warm water.
4. Place on tile and place a few drops of iodine.

If the leaf turns blue/black, you’ve got starch.

Question 2

What is the Inverse square law?

Answer 2

Inverse Square law = I / D²

Question 3

What part of the leaf does the most photosynthesis?

Answer 3

The Palisade Mesophyll.

Question 4

From the top to the bottom of a leaf, name the 5 parts of a leaf:

Answer 4

1. Waxy Cuticle.
2. Upper Epidermis.
3. Palisade Mesophyll.
4. Spongy Mesophyll.
5. Lower Epidermis.

Question 5

Where does gas exchange happen on a leaf?

Answer 5

The stomata.

Question 6

What controls the stomata?

Answer 6

Guard Cells.

Question 7

What does a waxy cuticle do?

Answer 7

Prevents water being evaporated.

Question 8

What is tropism?

Answer 8

The types of plant growth.

Question 9

Name the 3 types of tropism:

Answer 9

• Phototropism (Growth responding to Light.)
• Gravitropism (Growth that responds to gravity.)
• Hydrotropism. (Growth that responds to Water.)

Question 10

What is auxin?

Answer 10

A plant hormone that causes cell elongation.

Question 11

What does auxin do in:

1. Roots?
2. Shoots?

Answer 11

1. In roots, gravity pushes auxin to the base. In roots this causes growth where there isn’t auxin.
2. In shoots, auxin moves to the shaded side of the plant. This causes growth in the shaded side towards the light.

Question 12

What is Ethene?

Answer 12

A plant growth hormone that causes ripening.

Question 13

What is Gibberellins?

Answer 13

A plant growth hormone that causes seed germination, stem elongation, leaf expansion, pollen maturation, and flowering.