Topic 2 [Organisation of the Organism]

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Cells are the of life, as all living organisms are made out of cells. Cells exist in various and . There are smaller components called within a cell and each organelle performs a inside the cell or for the cell.

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- Also known as the .

- It is (Only allows some substances to pass through).

- The cell membrane is made of two layers. It had a (Love water) and a (Hate water) . Two layers of the head and tail connected together (Note that the tails are pointing towards each other) are called the .

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between the cell and its' external environment

: (Only present in plant cells and fungus)

- A rigid layer surrounding the of .

- In fungus, the cell was is made of .

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- To provide support and protection for the cell

- To prevent the cell from bursting in a dilute solution

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- Between the and the .

- Containing organelles, salts, dissolved gases, nutrients, enzymes, and other organic molecules.

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- Gives shape to the cell (Especially for animal cells, who do not have cell wall).

- Supports and protects the cell organelles

- Provides a medium for all to occur.

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- Bound by the .

- Containing .

**The nucleus contains . The chromosomes contain .**

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- Controls all cell activities

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- Small, dot-like organelles found in large numbers in .

Two types of Ribosomes:

1. Attached to the .

2. Occur in the .

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- To all types of .

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- A flat, sealed sac of .

- attached on its' surface.

- Present in .

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- and made by the ribosomes.

**Present in large amounts in cells that make proteins, such as gut cells.**

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- A tubular sac of .

- Does not have ribosomes.

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- and .

**Present in large amounts in cells that make lipids: e.g cells in the liver.**

: (Note that the plural of Mitochondrion is Mitochondria)

- Rod-shaped.

- Has an inner and outer membrane.

- 'The powerhouse of the cell'.

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- Carry out (Refer to Topic 1 definition of respiration), which release in the form of .

- is a molecule that acts as a energy source/currency for the cell.

**Cells with high rates of metabolism have high numbers of mitochondria.**

: (Only present in plants)

- Containing , , or .

- Largest organelle in plant cells as they store water.

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- For , , and .

: (Only present in plants)

- Have inner and outer membrane.

- Contain to trap energy from the sun.

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- To carry out .

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Animal Cells:

> Has NO cell walls, nucleus (in the middle of the cell), cytoplasm, NO chloroplast, NO vacuole, cell membrane.

> Stores food in the form of , which is made of a large number of glucose molecules binded together. Glycogen is stored in the .

Plant Cells:

> Has cell wall, nucleus (at the side of the cell), cytoplasm, chloroplast, vacuole, and cell membrane.

> Stores food in the form of , mostly in the .

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:The basic structure and of a living organism.

: A group of with similar function working together to perform a .

:A structure made up of a group of working together to perform a .

: A group of with related functions, working together to perform .

: Different work together to make up one whole functional and complete multicellular organism.

By the process of .

- The cells become according to the functions they have to form.

- All cells are made in the , and they call start out as , which are cells with no specific function.

- Stem cells and become .

- Layer of tiny hairs: '', which move and push from one place to another.

- The mucus transports and traps dust and microbes in the trachea when pushed by the cilia.

- Conduct , which convey messages (Stimulus).

- Electrical impulses travel along a long fibre called the .

- A provides insulation for the nerve cell.

- There are many connections () at each end of the nerve cell to keep passing on the electrical impulse.

- A shape.

- Transport from the lungs to tissues for .

- The cytoplasm of red blood cell contains , a red pigment that carries oxygen.

- Matured red blood cells have to make more space for , so more oxygen can be transported.

- Very to pass through narrow blood vessels.

- Egg Cell (Aka. ), the .

- It is fertilised by a sperm cell to form a .

- Sperm Cell, the .

- They have a tail (flagellum) for swimming.

- They have a high amount of mitochondria to provide energy to swim and penetrate the ovum.

- and from the soil.

- Has (root hairs) to increase for absorption.

- and up the plant.

- so water can pass freely.

- as many cells have joined together to form a continuos tube.

- Wall strengthened by , a waterproof substance.

- The hollow space in the vessel is called the .

- The cells are , , and .

: (Magnification)

Magnification = Size of illustration / Actual size

1 cm = 10 mm

1 mm = 1000 µm

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