BIOLOGY

Cell Membrane- Controlls what can enter and leave the cell.

Cytoplasm- A fluid where chemical reactions can occur.

Chloroplast- Contains a pigment called chlorophyll; which can turn light into energy.

Nucleus- Contains the genetic information(DNA).

Cell Wall- Provides support and protection.

Vacuole- For storage and support.

Leaf cell- Absorbs light energy for photosynthesis, packed with chloroplasts, regular shaped, closely packed cells form a continous layer for efficient absorbtion of sunlight.

Root hair cell- Abosorbs water and mineral ions from the soil,long 'finger like' process with very thin wall, which gives a large surface area.

Sperm cell- Fertilises an egg cell (female gamete), the head contains genetic information and an enzyme to help penetrate the egg cell membrane, The middle section is packed with mitchondria for energy, the tail moves the sperm to the egg.

Red blood cells- Contains haemoglobin to carry oxygen to the cells, thin outer membrance to let oxygen diffuse through easily, the shape increases the surface area to allow more oxygen to be absorbed efficiently, no nucleus, so the whole cell is full of haemoglobin.

IF we wanted to kill a plant, what three things would we 'limit'?

• LIGHT
• WATER
• CO2

These are called Limiting factors.

The Photosynthesis equation!

Carbon Dioxide + Water --> Oxygen + Glucose

Now.. balance out!

6CO2 + 6H2o ---> 6o2 + C6H12O6

Glucose...

• contains loads of chemical energy.
• has several hydrogen-carbon bonds.
• helps to grow new plant tissue.
• helps repair damages tissue.
• moves chemicals around and forms new chemicals.

An example of storage in a plant is the potatoe (starch).