The smart way to improve grades

Comprehensive & curriculum aligned

Affordable pricing from £10/month

Photosynthesis

In this worksheet, students will explore the limiting factors for photosynthesis.

'Photosynthesis' worksheet

Key stage:  KS 4

Curriculum topic:  Biology: Photosynthesis

Curriculum subtopic:  The Process of Photosynthesis

Difficulty level:  

down

Worksheet Overview

QUESTION 1 of 10

Plants make their own food using a process called photosynthesis. A green coloured substance - chlorophyll, found in the chloroplasts of plant cells - traps light. Light energy is used to turn carbon dioxide (from the air) and water (from the soil) into glucose. Another product of photsynthesis is oxygen. It is called a by-product, because it is not used by plants (apart from in respiration) and it is released into the atmosphere, where it is then breathed in by humans and animals. Glucose provides energy for growth of the plant and it is also stored as starch for later use, because starch does not dissolve in water. 

 

The chemical equation for photosynthesis is as follows:

 

 

In order for plants to grow, glucose is turned into cellulose to make new cell walls. Vegetable fats and oils are also made of glucose and stored for future use. We extract them from plants and use them for cooking.

 

Photosynthesis does not take place at night when there is no light from the sun, but it is possible to use artificial light. Farmers create conditions to increase the yield of their crops in greenhouses. They create optimum conditions for photosynthesis. The rate of photosynthesis depends on the availability of warmth, carbon dioxide and light intensity. The more of these, the higher the rate; but when the maximum rate is reached, it does not matter if light intensity and carbon dioxide concentration increase.

However, if the temperature exceeds the optimum (perfect) temperature, the photosynthesis rate decreases and even stops, because enzymes in the plant are denatured in high temperatures. The graphs below show how the rate of photosynthesis alters with different conditions:

 

What is the process used by plants to create their own energy? Type the word in the answer box below.

What substance in green plants absorbs light?

cell membrane

chloroplasts

chlorophyll

What are the reactants of photosynthesis? Select two boxes.

oxygen

hydrogen

water

soil

carbon dioxide

glucose

What are the products of photosynthesis? Select two boxes.

oxygen

hydrogen

water

soil

carbon dioxide

glucose

What do plant cells have that cannot be found in animals cells?

a nucleus

a cell membrane

chloroplasts

What substance is made of glucose and is used to build new cell walls in the growing plant?

chlorophyll

cellulose

chloroplasts

How do farmers store their plants, to provide optimum conditions for photosynthesis?

in greenhouses

in their own houses

in big open fields

What happens when the optimum concentration for carbon dioxide is reached?

photosynthesis rate decreases

photosynthesis stops

photosynthesis continues at the maximum rate

What happens when the optimum light intensity is reached?

photosynthesis continues at the maximum rate

photosynthesis rate decreases

photosynthesis stops

What happens when the temperature increases beyond the maximum point?
photosynthesis continues at the maximum rate

photosynthesis decreases and eventually stops

photosynthesis rate increases

  • Question 1

What is the process used by plants to create their own energy? Type the word in the answer box below.

CORRECT ANSWER
photosynthesis
EDDIE SAYS
Plants make their own food for their growth with photosynthesis.
  • Question 2

What substance in green plants absorbs light?

CORRECT ANSWER
chlorophyll
EDDIE SAYS
Chlorophyll is the green pigment in green plants which absorbs the energy from light that is necessary for photosynthesis to take place.
  • Question 3

What are the reactants of photosynthesis? Select two boxes.

CORRECT ANSWER
water
carbon dioxide
EDDIE SAYS
The reactants of any chemical equation come BEFORE the arrow. Carbon dioxide and water are the reactants of photosynthesis, and glucose and oxygen are the products.
  • Question 4

What are the products of photosynthesis? Select two boxes.

CORRECT ANSWER
oxygen
glucose
EDDIE SAYS
Glucose and oxygen are produced during photosynthesis. Oxygen is a by-product, as it is not used by the plant. Glucose provides the plant with energy for growth, as well as being stored for later use.
  • Question 5

What do plant cells have that cannot be found in animals cells?

CORRECT ANSWER
chloroplasts
EDDIE SAYS
Plant cells have organelles called chloroplasts, which are used for photosynthesis. Photosynthesis is a process which ONLY occurs in green plants. Plant and animal cells both have a nucleus and a cell membrane.
  • Question 6

What substance is made of glucose and is used to build new cell walls in the growing plant?

CORRECT ANSWER
cellulose
EDDIE SAYS
Cellulose is made of glucose and is used to build new cell walls as the plant grows.
  • Question 7

How do farmers store their plants, to provide optimum conditions for photosynthesis?

CORRECT ANSWER
in greenhouses
EDDIE SAYS
Farmers make greenhouses to increase the yield of their crops. They do this because they can control the conditions in the greenhouse, meaning that they can ensure the levels of carbon dioxide, water, warmth and light are all at the optimum level for the photosynthesis.
  • Question 8

What happens when the optimum concentration for carbon dioxide is reached?

CORRECT ANSWER
photosynthesis continues at the maximum rate
EDDIE SAYS
Photosynthesis continues at the maximum rate, as the plant will continue to photosynthesise regardless of how much carbon dioxide and light there is.
  • Question 9

What happens when the optimum light intensity is reached?

CORRECT ANSWER
photosynthesis continues at the maximum rate
EDDIE SAYS
Photosynthesis continues at the maximum rate, as the plant will continue to photosynthesise regardless of how much carbon dioxide and light there is.
  • Question 10
What happens when the temperature increases beyond the maximum point?
CORRECT ANSWER
photosynthesis decreases and eventually stops
EDDIE SAYS
When the temperature increases beyond the optimum point for photosynthesis, the rate of photosynthesis decreases and eventually stops, as plant enzymes are denatured due to the heat.
---- OR ----

Sign up for a £1 trial so you can track and measure your child's progress on this activity.

What is EdPlace?

We're your National Curriculum aligned online education content provider helping each child succeed in English, maths and science from year 1 to GCSE. With an EdPlace account you’ll be able to track and measure progress, helping each child achieve their best. We build confidence and attainment by personalising each child’s learning at a level that suits them.

Start your £1 trial

Start your trial for £1