Topic 6 - Plant Structures + Fuctions

Question 1

What are photosynthetic organisms?

Answer 1

Eg green plants. They’re the main producers of food + glucose is used to make complex molecules which make up their biomass.

Question 2

Describe photosynthesis is plants and algae

Answer 2

It’s an endothermic reaction that uses light to react carbon dioxide + water to produced glucose + oxygen

Question 3

What’s the word equation for photosynthesis?

Answer 3

Light

Carbon dioxide + water —> glucose + oxygen

Question 4

What’s the symbol equation for photosynthesis?

Answer 4

6CO2 + 6H2O —> C6H12O6 + 6O2

Question 5

Explain the effect of light intensity on rate of photosynthesis

Answer 5

As light intensity increases so does rate of photosynthesis as they’re directly proportional to each other up to a certain point as there would be another limiting factor

Question 6

Explain the effect of CO2 concentration on rate of photosynthesis

Answer 6

Increasing CO2 concentration increases rate of photosynthesis up to certain point. After this CO2 is no longer limiting factor

Question 7

Explain the effect of temperature on rate of photosynthesis

Answer 7

Temperature needs to be just right so enzymes can work at their optimum point. Too hot they denature + too cold they work slowly

Question 8

What are the limiting factors in photosynthesis?

Answer 8

Light intensity
CO2 concentration
Temperature

Question 9

What is the inverse square law?

Answer 9

Distance from light source and light intensity are inversely proportional to each other. As distance increases light intensity decreases.

Question 10

What is the equation for the inverse square law?

Answer 10

Light intensity ∝ 1 / (distance)²

Question 11

How is the structure of root hair cells adapted to absorb water + minerals?

Answer 11

Each root has millions of hairs —> plant has large surface area to absorb water + minerals from soil. Minerals absorbed by active transport + water absorbed by osmosis

Question 12

What do phloem tubes transport?

Answer 12

Living cells use energy to transport sucrose made in leaves to rest of plant

Question 13

How is the phloem adapted to it’s function?

Answer 13

Phloem tubes made of columns of elongated living cells with small pores in end of walls to allow stuff to flow through

Question 14

What does the xylem transport?

Answer 14

Carry water + mineral ions from roots to stem + leaves

Question 15

How is the xylem adapted to its function?

Answer 15

Tubes made of lignified dead cells joined end to end with no end walls between them + whole down middle

Question 16

How are water + mineral ions transported through the plant?

Answer 16

Transpiration —> caused by the evaporation + diffusion of water from plants surface.

Question 17

What is the structure of the stomata?

Answer 17

Tiny pores on the surface of a plant

Question 18

What is the function of the stomata?

Answer 18

They control water loss and gas exchange by opening and closing. They allow CO2 + oxygen to diffuse directly in + out of leaf.