PHOTOSYNTHESIS

Question 1

Nucleus?

Answer 1

An organelle which contains the genetic material that controls the cells activities, surrounded by its own membrane

Question 2

Cell membrane?

Answer 2

Forms the outer surface of the cell and controls the substances that go in and out

Question 3

Cytoplasm?

Answer 3

A gel-like substance where most of cells chemical reactions happen. It contains enzymes which control these reactions

Question 4

Mitochondria?

Answer 4

Small organelles where most of the reactions for aerobic respiration take place

Question 5

Ribosomes?

Answer 5

Small organelles where proteins are made in the cell

Question 6

Chloroplasts?

Answer 6

• Phss, which makes food for the plant happens here

- Contains a green substance called chlorophyll which is used in phss

Question 7

Cell wall?

Answer 7

• A rigid structure mae of cellulose, which surrounds the cell membrane
• It supports the cell and strengthens it

Question 8

Vacuole?

Answer 8

• A large organelle that contains cell sap

- It helps to support the cell

Question 9

Waxy cuticle?

Answer 9

• Water proof layer

- To help prevent water loss

Question 10

Upper epidermis?

Answer 10

• Thin and transparent

- To allow more light through the chloroplasts

Question 11

Palisade mesophyll?

Answer 11

• Contains lost of chloroplasts to absorb more light

- Packed closely together

Question 12

Spongy mesophyll?

Answer 12

• contains lost of air spaces

- to allow CO2 to diffuse through the leaf and increase the surface area

Question 13

Stomata?

Answer 13

Holes in the leaf to allow CO2 to diffuse in and O2 to diffuse out

Question 14

Guard cells?

Answer 14

• to open and close the holes

- to close to prevent water loss

Question 15

Testing a leaf for starch, THE BASICS

Answer 15

1. Use tweezers to place a leaf in boiling water
2. The leaf is then put into a boiling tube with some ethanol and heated in a water bath
3. The leaf is then rinsed in cold water and a few drops of iodine solution is added
4. If starch is present the leaf will turn blue-black

Question 16

Testing a leaf for starch, more detailed

Answer 16

1. Use tweezers to place a leaf in boiling water

(To stop any chemical reactions inside the leaf as enzymes will be denatured)

2. The leaf is then put into a boiling tube with some ethanol and heated in a water bath

(To remove chlorophyll and make the leaf a white-ish colour)

3. The leaf is then rinsed in cold water and a few drops of iodine solution is added
4. If starch is present the leaf will turn blue-black

Question 17

Phss chemical equation?

Answer 17

6CO2 + 6H20 -> C6H12O6 + 6O2

Question 18

Phss word equation?

Answer 18

carbon dioxide + water -> glucose + oxygen

Question 19

What are limiting factors?

Answer 19

• the rate of phss will be limited by the factor that is in the shortest supply
• if the factor is increased then phss will take place at a faster rate

Question 20

Examples of limiting factors?

Answer 20

• light
• CO2
• temperature

Question 21

Not enough light…?

Answer 21

Slows down the rate of phss

Question 22

Too little CO2…?

Answer 22

Slows down the rate of phss

Question 23

Light, limiting factor?

Answer 23

-if the light intensity is increased, the rate of phss will increase steadily but only up to a certain point

Question 24

CO2, limiting factor?

Answer 24

• Increasing the concentration of CO2 increases the rate of phss up to a certain point
• after this the graph flattens out showing that CO2 is no longer the limiting factor

Question 25

Temp, limiting factor?

Answer 25

• as the temp increases, so does the rate of phss, up to a point
• if the temp is too high, the enzymes will denature, so the rate of phss decreases