Unit 9C and 9D Lesson 1 Photosynthesis

1
Unit 9C and 9D Lesson 1 Photosynthesis

• Objectives to learn the different parts of the
  plant, to learn that light is the energy source
  for photosynthesis, and to learn the word
  equation for photosynthesis.
• Targets 1-7

2
Work to Do

• Read pages 82 and 83
• Complete questions 1-8.
• Homework
• Complete Activity Sheet C7S1
• Define the following keywords
• Stomata, chlorophyll, flower, glucose,
  photosynthesis, biomass, chloroplasts

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Parts of a Flowering Plant
The flower is the reproductive part of the plant.
It produces seeds which will grow into adult
plants.
Leaves are where photosynthesis take place. This
is where you find most of the chlorophyll in the
plant.
The stem gives the plant support and it helps to
position the plant in the sun. The stem also
carries water from the roots to the leaves.
The roots take water and minerals. They also
attach the plant to the ground and make sure it
doesnt blow away.
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Photosynthesis

• Photosynthesis is a chemical reaction. It is the
  way that plants convert energy from the sun into
  food.
• Four things are needed for photosynthesis
• In photosynthesis plants use sunlight to join
  molecules of water and carbon dioxide to form
  glucose. The plants then use glucose as food.
• If the plant doesnt need to use the glucose
  straight away it converts it to starch so that it
  can be stored.
• One of the products of photosynthesis is oxygen
  which we use to breath.

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Photosynthesis Formula

• The word equation for photosynthesis is
• Water carbon dioxide
  glucose oxygen

Sunlight
Chlorophyll
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Where Does the Carbon Dioxide and Water Come From?

• The plant gets its carbon dioxide from the air.
• The carbon dioxide enters the plants leaf through
  tiny holes called stomata. (One hole is called a
  stoma.)
• The oxygen which is produced by plants leaves the
  leaf through the stomata.
• The water comes from the soil and is absorbed by
  the roots.

Stoma
Stomata Animation
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Biomass

• Biomass is a measure of how much mass a plant
  has. In other words how much of the plant there
  is.
• The glucose which is created along with minerals
  absorbed by the roots are turned into several
  different chemicals.
• These chemicals help the plant to grow and add to
  its biomass.

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Factors Which Affect Photosynthesis

• An increase in the amount of light will increase
  the rate of photosynthesis.
• An increase in the amount of carbon dioxide will
  increase the rate of photosynthesis.
• An increase in temperature will increase the rate
  of photosynthesis. (This is until it gets too
  hot then there will be a sharp decrease in the
  rate of photosynthesis.)