شرح منهج العلوم كامل 2009 بالانجليزي

[ولاء حمدان]

Plant makes its own food

- How does the plant obtain its food?
Plants do not eat food the way animal do.
The plant makes its own food through photosynthesis process.

Photosynthesis process:
Is a vital process that takes place in the plant "espacially the leaves" in the presence of:
- Light energy "sunlight"
- Water
- Carbon dioxide gas
- Chlorophyll.

Chlorophyll:
- Is a pigment which makes plants look green and absorb light energy.
Sunlight is essential for photosynthesis:





Chlorophyll is necessary for photosynthesis process:


- The variegated leaf:
It contains parts with chlorophyll "green" and other parts have no chlorophyll "white".

- Carbon dioxide is essential for photosynthesis:

oxygen is produced during photosynthesis:


- The importance of photosynthesis process:
- During photosynthesis plants make the food which animals and human beings need.
- Plants renew the air by replacing the oxygen used in vital processes.
- Plants remove the carbon dioxide form the air through photosynthesis.

- the green plants are producing organisms "producers" for their food.
- Plant leaves are food factories.
- Carbon dioxide enters the plant through stomata
Somata:
- They are small opening on both sides of the leaf.
- The number of stomata of the lower surface of the leaf is more than those of the upper surface of the same plant leaf.



- Molecules of sugar "glucose" are joined together to form starch.
- Starch itself can change to fats or proteins in plant cells in the presence of some materials made by the plant and some salts.