1. Cell Structure & Function

2. Cell Theory All living things are made up of cells.
Cells are the smallest working units of all living things.
All cells come from pre-existing cells through cell division.

3. They were first identified in 1665.
Definition of Cell
A cell is the smallest unit that is capable of performing life functions.
They were first identified in 1665.

4. Examples of Cells Amoeba Proteus Plant Stem Bacteria Red Blood Cell
Nerve Cell

5. Prokaryotic Eukaryotic
Two Main Types of Cells
Prokaryotic
Eukaryotic

6. Prokaryotic Do not have structures surrounded by membranes
Few internal structures
One-celled organisms – an example would be bacteria

7. Eukaryotic Contain organelles surrounded by membranes
Most living organisms
Plant
Animal

8. “Typical” Animal Cell

9. “Typical” Plant Cell

10. Cell Parts
Organelles

11. Surrounding the Cell

12. Plasma (Cell) Membrane
Outer membrane of cell that controls movement in and out of the cell
Maintains the internal environment
Very thin – less than 0.1µm thick
Double layer

13. Cell Wall Found in plant cells, fungi & bacteria
Lie on the outside of the plasma membrane
Supports & protects cells
Semi-rigid – helps hold plants upright

14. Inside the Cell

15. Nucleus The control centre of the cell - directs cell activities
Separated from cytoplasm by nuclear envelope (membrane)
Contains genetic material - DNA

16. Nuclear Envelope (Membrane)
Surrounds nucleus
Made of two layers
Openings called nuclear pores allow material to enter and leave nucleus
Having a nuclear envelope distinguishes an eukaryotic cell

17. Chromosomes
During the process of cell replication, the DNA in the nucleus becomes organized into chromosomes
Contain instructions for traits & characteristics

18. Nucleolus Inside nucleus Contains RNA to build proteins

19. Cytosol (Cytoplasm) Gel-like mixture Surrounded by the plasma membrane
Contains hereditary material

20. Endoplasmic Reticulum
Membranous sacs that package materials, such as proteins, for transport within the cell
Smooth type: lacks ribosomes
Rough type (pictured): ribosomes embedded in surface

21. Golgi Complex (Bodies, Apparatus)
Move proteins out of the cell
Protein 'packaging plant‘
Are formed from layers of membranes and vesicles that carry materials out of the cell

22. Ribosomes Each cell contains thousands
Make proteins (‘protein factories’) – this is called protein synthesis
Found on endoplasmic reticulum & floating throughout the cell

23. Mitochondria
Produces chemical energy (ATP – adenosine triphosphate) through chemical reactions – breaking down fats & carbohydrates
Controls level of water and other materials in cell
Recycles and decomposes proteins, fats, and carbohydrates

24. Lysosome Digestive 'plant' for proteins, fats, and carbohydrates
Transports undigested material to plasma membrane for removal
Sometimes the lysosome releases its enzymes and causes the cell to undergo a ‘controlled death’ (for a variety of reasons) - this ‘self-destruction’ is called apoptosis

25. Vacuoles Membrane-bound sacs for storage, digestion, and waste removal
Contains water solution
Help plants maintain shape

26. Chloroplast Found only in plant cells Contains green chlorophyll
Where photosynthesis takes place

27. Cytoskeleton The cytoskeleton is unique to eukaryotic cells.
It is a dynamic three-dimensional structure that fills the cytoplasm.
This structure acts as both muscle and skeleton, for movement and stability.

28. Flagella and Cilia
Typically, cells possess one or two long flagella, whereas ciliated cells have many short cilia.
The mammalian spermatozoon has a single flagellum to move the sperm through the Fallopian tubes.
Huge numbers of cilia cover the surfaces of mammalian respiratory passages (the nose, pharynx, and trachea), where they dislodge and expel particulate matter that collects in the mucus secretions of these tissues.