Photosynthesis and Limiting Factors

Question 1

What does Photosynthesis do?

Answer 1

It uses energy to change carbon dioxide and water into glucose and oxygen

Question 2

Where does Photosynthesis take place?

Answer 2

It takes place in the chloroplasts in green plant cells

Question 3

What is in the Chloroplasts and what does it do?

Answer 3

The chloroplasts contains pigments like chlorophyll that absorb light

Question 4

How is energy transferred from the Chloroplasts?

Answer 4

It is is transferred from the environment by light

Question 5

Photosynthesis is Endothermic, What does this mean?

Answer 5

That the energy is transferred from the environment in the process

Question 6

What is the word equation for photosynthesis?

Answer 6

light

carbon dioxide + water 🡲 glucose + oxygen

Question 7

What is the symbol equation for photosynthesis?

Answer 7

light

6CO2 + 6H2O 🡲C6H1206 + 602

Question 8

What are the five ways plants use glucose?

Answer 8

For respiration, Making cellulose, Making amino acids, Storing as oils or fats, Storing it as starch

Question 9

How do plants use glucose for respiration?

Answer 9

Through respiration plants can transfer energy from glucose which enables them to convert the rest of glucose into various useful other subtances

Question 10

How do plants use glucose to make Cellulose?

Answer 10

It is converted into Cellulose for making strong plant cell walls

Question 11

How do plants use glucose to make amino acids?

Answer 11

Glucose is combined with nitrate ions (absorbed from the soil) to make amino acids which are then made into proteins

Question 12

How do plants use glucose to store it as lipids?

Answer 12

Glucose is turned into lipids (fats and oils) for storing in seeds

Question 13

How do plants use glucose to store it as starch?

Answer 13

Glucose is turned into starch and stored in the roots, stems and leaves, ready for use when photosynthesis isn’t happening, like in the winter. As starch is insoluble
it means it is much better for storing than glucose- a cell with lots of glucose would draw in lots of water and swell up

Question 14

What is the rate of photosynthesis affected by?

Answer 14

the intensity of light, concentration of CO2 and the tempurature

Question 15

What is meant by a limiting factor?

Answer 15

When any of the factors effecting photosynthesis stop it from happening any faster

Question 16

What environmental conditions can which the factors effecting photosynthesis become the limiting factor?

Answer 16

Light- At night
Temperature- At Winter
CO2- If its warm enough and bright enough

Question 17

How can chlorophyll also be a limiting factor?

Answer 17

The amount of chlorophyll in a plant can be effected by disease (e.g. infection with the tobacco mosaic virus?)
or environmental stress such as lack of nutrients. These factors can cause chloroplasts to become more damaged or not to make enough chlorophyll. This means the rate of photosynthesis is reduced because they cant absorb as much light