B4 - Leaves and photosynthesis

Question 1

What is the green colour in plants caused by?

Answer 1

Green chloroplasts in plant cells which contain green pigments called chlorophyll.

Question 2

What does the vacuole do?

Answer 2

The vacuole holds water and gives shape to the cell.

Question 3

What does the cell wall do?

Answer 3

The cell wall gives the cell support.

Question 4

What is a palisade?

Answer 4

Tightly packed cells found in the upper layer of a leaf.

Question 5

What is a spongy mesophyll?

Answer 5

Found in the middle of a leaf with large air spaces between.

Question 6

What are guard cells?

Answer 6

Guard cells are specialized cells in the epidermis of leaves, stems and other organs that are used to control gas exchange.

Question 7

What are vascular bundles?

Answer 7

A strand of conducting vessels in the stem or leaves of a plant, typically with phloem on the outside and xylem on the inside.

Question 8

How are leaf cells adapted for photosynthesis?

Answer 8

• the epidermis is thin and transparent allowing light through
• the palisade cells have lots of chloroplasts to absorb a lot of light
• air spaces between mesophyll cells allow gases to diffuse easily
• mesophyll are small and irregular increasing surface area to volume radio

Question 9

What part of the plant takes in gas?

Answer 9

The stomata on the underside of the leaves.

Question 10

How are leaves adapted for photosynthesis?

Answer 10

• being broad so it has a large surface area to absorb light
• being thin so gases do not have far to diffuse
• having a network of cells in vascular bundles to support it
• having stomata to allow carbon dioxide to diffuse into it and oxygen out
• having guard cells which control the size of the stomata during the day and night