1. Cells

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

3. these functions include:
Organelles
Organelles are:
↙ ↓ ↘
Specialised Structures have certain shapes perform specific functions
these functions include:
↙ ↙ ↓ ↘ ↘
Growth Metabolism Reproduction Respiration Excretion
↙ ↓ ↘
Movement Irritability Maintenance O²

4. Functions Respiration
Controlled absorption of oxygen combines with nutrients and produces energy and ATP. The waste product is carbon dioxide.
Excretion
Any harmful waste is removed e.g. Uric acid and Carbon Dioxide
Growth
Cells grow and repair by producing protein.
Movement
Some cells such as blood cells can move, parts of cells move but usually in one direction
Reproduction
All cells grow and then most reproduce themselves either by mitosis (simple cell division) or meiosis (sexual reproduction)
Metabolism
Chemical reactions:
Anabolism – a chemical reaction for growth and repair by producing proteins
Catabolism - a chemical reaction for the breakdown of substances for energy and waste
Sensitivity
Cells respond to external stimuli

5. Cell Structure

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

7. Organelles and their functions
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.

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.

14. Draw and colour your own picture of a cell.
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