Plant Structures T6

Question 1

What happens during photosynthesis?

Answer 1

Photosynthetic organisms such as green plants and algae use energy from the sun to make glucose

Question 2

What is biomass?

Answer 2

The mass of living material

Question 3

What is the chemical reaction for photosynthesis?

Answer 3

Carbon dioxide + water =(light)= glucose + oxygen

Question 4

What kind of reaction is photosynthesis?

Answer 4

Photosynthesis is an endothermic reaction, energy is taken in

Question 5

What 3 factors affect the rate of photosynthesis?

Answer 5

Light intensity, concentration of CO2, and the temperature

Question 6

How can you measure the rate of photosynthesis?

Answer 6

Use pondweed and measure the rate of oxygen that comes out, the more oxygen means that there is a higher rate of photosythesis

Question 7

What happens with photosynthesis when light intensity increases

Answer 7

The rate of photosynthesis will steadily increase until a certain point, beyond that it wont make any difference.

Question 8

What happens when carbon dioxide levels decrease?

Answer 8

CO2 is one of the raw materials needed for photosynthesis. If there is too little CO2 then the rate of photosynthesis will slow.

Question 9

What do root hair cells do and how do they complete this job efficiently?

Answer 9

The cells on the surface of plant roots grow into ‘hairs’, which stick out into the soil. Each branch of root will be covered in millions of hairs, which have a larger surface area so they will absorb more minerals and water

Question 10

What do phloem tubes do?

Answer 10

Phloem tubes transport food. They are made of elongated living cells with small pores in the end walls to allow stuff to flow through it. They transport food substances made in the leaves to the rest of the plant

Question 11

What do xylem tubes do?

Answer 11

Xylem tubes take water up. They are made of dead cells joined end to end with no cell walls between the and a hole down the middle . They only carry water and mineral ions

Question 12

What is transpiration?

Answer 12

The loss of water from a plant

Question 13

How does transpiration occur?

Answer 13

Transpiration is caused by the evaporation and diffusion of water from a plant’s surface. Most transpiration happens at the leaves.

Question 14

What are stomata?

Answer 14

Stomata are tiny pores on the surface of a plant. They are mostly found on the lower surface of the leaves. Stomata allow CO2 and oxygen to diffuse directly in and out of a leaf. They also allow water vapour to escape during transpiration

Question 15

What 3 factors increase transpiration rates?

Answer 15

Light intensity, temperature, and air flow

Question 16

What piece of apparatus measures transpiration?

Answer 16

Potometer

Question 17

Features of a leaf?

Answer 17

Leaves are broad, so there’s a large surface area exposed to light, which is needed for photosynthesis.

Question 18

What is the palisade layer?

Answer 18

The palisade layer has lots of chloroplasts. This means that they’re near the top if the leaf where they can get the most light

Question 19

What is the upper epidermis?

Answer 19

The upper epidermis is transparent so that light can pass through to the palisade layer.

Question 20

How are plants with small leaves adapted to their environment?

Answer 20

Plants with small leaves reduce surface area for water loss by evaporation. Spines also help stop animals eating the plant

Question 21

What are auxins?

Answer 21

Auxins are plant hormones which control growth at the tips of shoots and roots

Question 22

What are phototropic?

Answer 22

Shoots are positively phototropic (grow toward light) and roots are negatively phototropic (grow away from light)

Question 23

What are gravitropic?

Answer 23

Shoots are negatively gravitropic (grow away from gravity) and roots are positively gravitropic (grow toward gravity)

Question 24

How can plant hormones be used commerically?

Answer 24

As selective weedkillers
Growing from cuttings with root powder
Controlling flower and fruit formation
Producing seedless fruit
Controlling the ripening of fruit
Controlling seed germination