Science 5 Unit 4 Cells

Unit 4 Cells and their functions

4.1 Different kind of cells and their functions

Cells is the smallest unit of life. They came in different shape and size. 

They can be found in living things.

Different Cells in human body:

Muscle cells             :	Contract and relax to allow us to move our body
Skin cells                 :	Form a barrier that prevents harmful substances from entering our body
Nerve cells               :	Carry massages between our brain and other parts if the body
Red blood cells        :	Carry oxygen from our lungs to other part of our body
White blood cells    :	Protect our body against disease
Bone cells                :	Give our body shape and allow us to move.
Gamete cells            :	Needed for reproduction.

Different cells in plants:

Guard cells              :	Found in leave Control the openings called stomata Stomata allow gases to move in and out of the leaves
Mesophyll cells        :	Contain the structure chloroplast which contain chlorophyll Chlorophyll traps light energy from the sun to make food
Xylem cells              :	Xylem cells form a Xylem Xylem transport water and mineral salts from the roots to other parts.
Sieve tube cells        :	Sieve tube cells needed to form the phloem. Phloem transport food from the leaves to other parts of the plant.
Root hair cells         :	Found in the roots Absorb water and mineral salts from the soil.

4.2 Cells need energy

Food provide energy for living things.

Living things need energy for breathing, moving, growing, and other life processes.

Cells need energy to carry out their functions, to grow, to carry out cell division and to move substance in and out of cells.

Science 5 Unit 4 exercise