1

Cells have chloroplasts.

The green chlorophyll traps light energy.

2This is the inside of a leaf.

The top cells have many chloroplasts and no gaps.

Air spaces let gases move around.

Veins bring water to the cells.

3

Thin, flat leaves catch light.

They have a large surface area.

4

Leaves do not overlap.

5

Guard cells let in gases through pores called stomata but can close to stop the leaf wilting.

6

Stiff, woody stems hold leaves high to get light.

7

Climbing plants twist around objects or have special “roots” along their stems.

They climb up to get light.

8

Evergreens keep their leaves all year.

9

Woodland plants grow early before trees block the light.

10

Water plants have gas filled structures to float near the surface where most light is.

11The pondweed apparatus was used in two investigations. Here are the results: A – To find out if temperature affects photosynthesis.

Temperature (oC) Number of bubbles in 1 minute 15 5 30 17 45 38 60 0

B – To find out if the colour of light makes a difference to photosynthesis.

Colour of light Number of bubbles in 1 minute blue 27

green 4 yellow 16

red 24 Draw a bar chart to display each set of results. Write a conclusion for each investigation.