Cells

1. Cells

2. Components – organelles Nucleus Nucleolus Nuclear membrane Cytoplasm Cell membrane Rough Endoplasmic Reticulum Smooth Endoplasmic Reticulum Mitochondria Ribosomes Lysosomes Vacuole Centrosome Centrioles Golgi Complex Cells

3. Organelles Organelles are: ↙ ↓ ↘ Specialised Structureshave certain shapes perform specific functions these functions include: ↙ ↙ ↓ ↘ ↘ Growth Metabolism Reproduction Respiration Excretion ↙ ↓ ↘ Movement IrritabilityMaintenance O²

4. Functions

5. Cell Structure

6. Task • Write down 5 organelles in a cell and see if you can remember their specific functions

7. Nucleus The ‘BRAIN’ of the cell Contains DNA – this is our genetic information, a segment of DNA located in a set position on a chromosome is a gene these contain hereditary information and control most cellular structure and function. Chromosomes are thread like structures contained within the cell nucleus. 46 chromosomes normally make up somatic (body)cells, these cells divide by mitosis. The nuclear membrane allows the passage of substances in and out of the nucleus. Organelles and their functions

8. Organelles and their functions • Cytoplasm • The fluid part of the cell, a jelly like substances with organelles embedded within. • Found inside the cell but outside the nucleus. • Cell membrane • The cell membrane surrounds the cell keeping everything inside, but letting other substances out such as waste • Known as a semi-permeable membrane meaning it has pores to allow movement. It allows the passage of substances in and out of the cell. • It is made up of proteins and lipids (fat)

9. Organelles and their functions Nucleolus Important in the production of ribosomes. Situated inside the nucleus. Nuclear Membrane Surrounds the outside of the nucleus. Allows passage of substances in and out.

10. Organelles and their functions • Smooth + Rough Endoplasmic Reticulum • A network of canals through the cytoplasm to allow substances to move around • ‘The circulation of the cell’ • Mitochondria • It is known as the powerhouse of the cell as it supplies the cell with its energy • A chemical reaction that takes place here results in the release of ATP – Adenosine Triphosphate. ATP transports energy around the body.

11. Organelles and their functions • Ribosomes • Known as the protein factories of the cell • Produce enzymes for growth and repair • Lysosomes • Destroys worn out parts of the cell and bacteria • Breaks down food for energy • Vacuoles • Empty spaces in the cytoplasm

12. Organelles and their functions • Centrosomes • Dense area of cytoplasm that contains the Centrioles • Centrioles • Paired cylindrical structures at right angles to each other inside the centrosomes • Play an important part in Mitosis • Golgi complex • Creates the communication network in the cell, consisting of flattened channels stacked on one and other • Packages secreted proteins • Lipid secretion and carbohydrate synthesis

13. How cells function • Watch the following short video on the functions of cells. Make notes if you would like to. • http://www.youtube.com/watch?v=NiiLS_ovLwM&feature=related

14. Task • Draw and colour your own • picture of a cell. • Remember use individual flare and pictures to help you remember the functions.

15. Cell Division It takes approximately two hours to take pace and happens in five phases: Prophase - • The production phase • Centrosome divides • Centioles rearrange themselves at either end of the cell • DNA shortens and thickens • Chromosomes begin forming • Nucleoli disappear Metaphase - • The meeting phase • Nuclear membranes disappear • Energy is provided by the mitochondria • Chromosomes align themselves in the centre of the cell in pairs

16. Anaphase - • The away phase • Spindle fibres begin to disintegrate • Chromosomes are pulled towards the Centrioles • Telophase - • Fibres spindles completely disintegrate • Nuclear membrane surrounds the nuclear matter • Interphase – • The resting phase • Cells increase in size • DNA is being reproduced