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Flashcards in The rate of photosynthesis Deck (19)
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1
Q

What effects the rate of photosynthesis?

A

Intensity of light
Volume of CO2
Temperature
Water (however a plant has other bigger problems if it doesn’t have enough water)

2
Q

What’s the term for something that makes the rate of photosynthesis slower?

A

Limiting factor

3
Q

What is the limiting factor at night?

A

Light

4
Q

What is the limiting factor in winter?

A

often the temperature

5
Q

What is the limiting factor when it is warm and bright enough?

A

Usually CO2

6
Q

What experiment should you do to work out a plant’s ideal conditions for photosynthesis?

A

The bubble experiment
Eg. With pondweed, count the bubbles it produces (Oxygen) and test which light level (by moving the light) produces the most bubbles.

7
Q

As the light level is raised, the rate of photosynthesis [ ] [ ] - but only up to a certain point! (It’s the with [ ] level)!

A

increases steadily

CO2

8
Q

Why does the rate of photosynthesis become constant after a certain point when you increase the light level?

A

Something else becomes a limiting factor (Temp or CO2)

9
Q

Describe a way you can control the level of CO2

A

Dissolve different amounts of sodium hydrogencarbonate in the water, which gives off CO2

10
Q

Why is temperature usually the limiting factor?

A

The temp is usually too low, therefore the enzymes, needed for photosynthesis work more slowly

11
Q

What happens when the temp gets too high?

A

The enzymes get damaged (denature), at around 45°C, and stop working which means photosynthesis stops

12
Q

How could you keep something at a constant temp, in an experiment?

A

Use a water bath

13
Q

The most common way to create the ideal [ ] for plants is to grow them in a [ ].

A

environment

greenhouse

14
Q

How to greenhouses stop temp becoming a limiting factor?

A

They trap the sun’s heat so it is warm enough however, it can get too hot

15
Q

What do you do if your greenhouse is too hot?

A

Use shades or ventilation

16
Q

How to farmers ensure light isn’t a limiting factor?

A

They use artificial light after the sun goes down to increase the rate of photosynthesis

17
Q

How to farmers ensure CO2 isn’t a limiting factor?

A

They use paraffin heaters to heat the greenhouse. A by-product of burning paraffin in Carbon Dioxide

18
Q

What does using a green house also prevent? (Not a limiting factor)

A

Prevents pests and diseases

19
Q

How do farmers provide the minerals for the plants?

A

Fertalisers