Topic 6

Question 1

Where does photosynthesis take place?

Answer 1

Leaves of plants/plant cells/chloroplasts

Question 2

Why do plants photosynthesis?

Answer 2

To make food such as glucose to build new cells so the plant can grow.

Question 3

What is the chemical chlorophyll used for?

Answer 3

Absorbing light

Question 4

How do plants gain water?

Answer 4

Absorbed through the plant roots

Question 5

What reacts to make glucose and oxygen?

Answer 5

Carbon dioxide and water

Question 6

What is the glucose used in?

Answer 6

Used in a process called respiration or converted into chemicals such as starch which is then stored

Question 7

What is oxygen?

Answer 7

By product of photosynthesis

Question 8

What is the endothermic reaction for photosynthesis?

Answer 8

Carbon dioxide + water → glucose + oxygen
6CO² + 6H²O → C6H¹²O6 + 6O²

→= sunlight and chlorophyll

Question 9

Why don’t animals photosynthesis

Answer 9

Because we don’t have chlorophyll and we can move to find food. Also we get energy from the food.

Question 10

Waxy cuticle functions

Answer 10

Thin - short distance for light to travel - light is the energy source for photosynthesis.
Waterproof - reduces water loss - water is a reactant in photosynthesis.

Question 11

Upper epidermis function

Answer 11

Transparent - allows more light to pass through to the palisade cells - more light is available for photosynthesis.

Question 12

Palisade mesophyll cells functions

Answer 12

Many chloroplasts located at the top of the cell - this allows for maximum light energy to be absorbed - light energy is needed for photosynthesis.

Question 13

Spongy mesophyll cell function

Answer 13

Air spaces - allow gases to pass in and out of the leaf (gaseous exchange) - this means that the reactant (Carbon dioxide) can get to the palisade cells and the product (Oxygen) can exit the leaf.

Question 14

Guard cells / stomata function

Answer 14

Holes - which open and close - allow gaseous exchange to occur - so palisade cells gain reactants and can remove the by-product Oxygen.

Question 15

What are the 3 limiting factors of photosynthesis?

Answer 15

Light intensity
Temperature
Carbon dioxide concentration

Question 16

Root hair cell

Answer 16

Live cells that carry water and dissolved minerals ions form the soil into the roots and towards the xylem. Only one way.

Question 17

Xylem vessels

Answer 17

Dead cells that transport the water and minerals needed for transpiration from the roots towards the stem and leaves. Only one way.

Question 18

Phloem tissue

Answer 18

Live cells transport food substances such as glucose and sucrose from the leaves to the plant or storage organs. Direction of travel is up and down.

Question 19

Stomata

Answer 19

Live cells that allow gases such as Carbon dioxide, water vapour and oxygen to pass in and out the leaf.

Question 20

Root Hair cell adaptation

Answer 20

1) Long hair like extensions on roots provide a large surface are for quick absorption of water and mineral ions.
2) Thin cell walls provide a short diffusion pathway for water to be absorbed by osmosis.

Question 21

Xylem tissue Adaptation

Answer 21

1) Lignified hollow tubes providing strength to stop tubes bursting or collapsing.
2) No end cell walls so water flow is not slowed down.
3) No cytoplasm allowing water to flow more quickly.
4) Tiny pores allowing water and minerals to enter and leave the xylem vessels.

Question 22

Phloem tissue adaptation

Answer 22

Elongated living cells called sieve tubes:

1) Small pores in the end cell walls of sieve cells allowing liquids to flow from one sieve tube to the next
2) Small amounts of cytoplasm giving more space for the flow of substances (sucrose solution)
3) Pores in the side of the sieve cells connecting to comparison cells allowing sucrose to be pumped in and out of the sieve cells.