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Flashcards in Cellular Organisation (UNIT 2) Deck (10):
1

CELL DIFFERENTIATION

The process by which each cell becomes specialised in structure to suit the role that it will carry out.

2

Where do all cells in an organism derive from?

mitotic division of the fertilised egg.
They all have the same genes.

3

How does a cell differentiate?

Every cell contains the genes needed for it to develop into any one of the many different cells in an organism. But only a few of these genes are are switched on (expressed) in any one cell. Different genes are switched on in each type of differentiated cell. The rest are switched off.

4

TISSUE

A group of similar cells organised into a structural unit that perform a specific function

5

Give two examples of tissues. Describe.

-Epithelial tissues, found in animals and consist of sheets of cells. They line the surfaces of organs and often have a protective or secretory function.

-Xylem- Occur in plants and is made up of a number of cell types. Used to transport water and mineral ions throughout the plant and also gives mechanical support.

6

ORGAN

A combination of tissues that are coordinated to perform a variety of functions.

7

Explain how the tissues in the stomach work to digest food.

-Muscle to churn and mix the stomach contents,
-Epithelium to protect the stomach wall and produce secretions.
-Connective tissue to hold together the other tissues.

8

Describe and explain the tissues that make up a leaf(organ)

-Palisade mesophyll made up of leaf palisade cells, that carry out photosynthesis.

-Spongy mesophyll adapted for gaseous exchange

-Epidermis to protect the leaf and allow gaseous diffusion.

-Phloem to transport organic materials away from the leaf.

-Xylem to transport water and ions into the leaf.

9

Organ systems

Multiple organs working together to perform a particular function.

10

Describe 3 organ system in humans.

-DIGESTIVE SYSTEM- digests and processes food. Made up of organs that include the salivary glands, oesophagus, stomach, duodenum, ileum, pancreas and liver.

-THE RESPIRATORY SYSTEM- is used for breathing and gas exchange. It is made up of organs that include the trachea, bronchi and lungs.

-THE CIRCULATORY SYSTEM- pumps and circulates blood. It is made up of organs that include the heart, arteries and veins.