# The Rate of Photosynthesis

• Created by: 12eyoung
• Created on: 01-06-17 20:34
What effects the rate of photosynthesis?
The intensity or LIGHT, the volume of CO2 and TEMPERATURE (water can become a limiting factor if plant is short of water).
1 of 20
What does the limiting factor depend on?
The environmental conditions
2 of 20
What is a limiting factor?
Something that stops photosynthesis from happening any faster.
3 of 20
What is the limiting factor at NIGHT
Light is the limiting factor
4 of 20
What is the limiting factor in WINTER
Temperature
5 of 20
CO2
If it is warm enough and bright enough, CO2 is usually limiting.
6 of 20
What experiment can you do to see the ideal conditions for photosynthesis?
Count the number of bubbles given off in a given time to see how FAST photosynthesis is happening
7 of 20
Not enough LIGHT slows down the rate of photosynthesis
1) Light provides the ENERGY needed for photosynthesis 2) As LIGHT LEVEL is raised, rate of photosynthesis INCREASES STEADILY - but only up to a certain point. --> Beyond that, it won't make any difference (temperature or CO2 level will be limiting)
8 of 20
How can you change the light intensity?
Moving a lamp closer to or further away from plant.
9 of 20
How to measure the light intensity?
using a LIGHT METER
10 of 20
Too little CARBON DIOXIDE also slows it down
Will only increase photosynthesis to a point --> graph will FLATTEN OUT showing CO2 is no longer the limiting factor.
11 of 20
How can you control the amount of CO2?
Dissolve different amounts of SODIUM HYDROGENCARBONATE in water
12 of 20
TEMPERATURE
1) The temperature has to be just right --> if temperature is the limiting factor, it's because it is too LOW for enzymes to work properly --> photosynthesis works more SLOWLY at low temperatures.
13 of 20
What happens if the plant gets too hot? (45C)
Enzymes will become damaged
14 of 20
How can you control the temperature?
Putting the flask in to a WATER BATH
15 of 20
CONTROL VARIABLES in photosynthesis experiments
1) Keep the light the same distance from plant (to control light intensity) 2) keep flask in a WATER BATH (to keep temperature CONSTANT).
16 of 20
What is the most common way to artificially create the ideal environment?
Grow plants in a greenhouse
17 of 20
What do greenhouses do?
1) help TRAP sun's heat 2) makes sure temperature doesn't becoming limiting.
18 of 20
Greenhouses in winter, summer & when Sun goes down
Gardener can use a heater to keep temperature at ideal level 2) In summer, can use ventilation to cool down temp. 3) Supply artificial light when Sun goes down
19 of 20
How can farmers increase the level of CO2?
use a paraffin heater
20 of 20

## Other cards in this set

### Card 2

#### Front

What does the limiting factor depend on?

#### Back

The environmental conditions

### Card 3

#### Front

What is a limiting factor?

### Card 4

#### Front

What is the limiting factor at NIGHT

### Card 5

#### Front

What is the limiting factor in WINTER