Year 7 Cell organisation J.Maden

1. De Lisle Catholic Science CollegeScience departmentKey stage 3 Year 7 Cell organisation J.Maden

2. Growth • What happens to an egg cell after fertilisation by a pollen cell or a sperm cell? • the fertilised egg cell divides many times and forms a small ball of identical cells • Where do different types of cell come from? • the ball of cells continue to divide but groups of different types of cell start to form • these different cells do different jobs

3. Cell specialisation The following slides give examples of how cells have been modified to do different jobs

4. Root hair cell of a plant • Role: • Absorbing water and mineralsfrom the soil • Adaptations: • Projection increases the surface areaof the cell membrane

5. Palisade cell of a leaf • Role: • Makes food by photosynthesis • Adaptations: • Many chloroplasts • Cells arranged on their ends

6. Nerve cell • Role: • Transmitting electrical impulses • Adaptations: • Can be very long • Connections for attaching to other nerve cells

7. Cell with cilia • Role: • Moving tiny bits of material • Adaptations: • Whip-like hairs all thrash together

8. Muscle cell • Role: • To create movement by getting shorter • Adaptations: • Have many mitochondria for energy release by the process of respiration

9. Red blood cell • Role: • Transportation of oxygen • Adaptations: • Bi-concave disc-shape for maximum surface area • Packed with haemoglobin molecules for oxygen transport (no nucleus)

10. Sperm cell • Role: • Fertilisation of an egg cell • Adaptations: • Tail for movement • Nucleus contains chromosomes

11. Egg cell • Role: • To divide and form a new organism after fertilisation by a sperm cell • Adaptations: • Large cell; contains a food store • Nucleus contains chromosomes

12. Tissues • What is a tissue? • the name for a group of similar cells that do the same job? • Give examples of different types of tissues: • muscle tissue is made up of groups of muscle cells • nerve tissue is made up of groups of nerve cells • xylem tissue in a plant stem is made up of xylem cells

13. Organs • What is an organ? • the name of a collection of different types of tissue working together to do a job • Give an example of an organ: • the heart • pumps blood around the body • is built from muscle, skin and nerve tissue

14. Organ systems • What is an organ system? • group of organs working together to do a job • Give an example of an organ system: • the digestive system • breaks down food and moves it into the circulatory system • made up of several organs including • stomach, gall bladder, pancreas, small intestine, large intestine

15. muscle cell skin cell basic building unit similar cells working together muscle tissue skin tissue different tissues working together heart different organs working together circulatory system complete living thing whale

16. Position of some body parts Notice that the person is smoking a cigarette Brain Heart She knows that it will cause her to have an early death Stomach Lungs She has become addicted to the nicotine in the cigarette and cannot help herself Kidneys Liver Pelvis Bladder

17. Year 7 Cell organisation Click here to view again