Cell Parts and Functions

1. Cell Parts and Functions The Cell Revisited

2. An Animal Cell

3. A Plant Cell

4. Animal and Plant Cell Organelles • Similar to an organ in our bodies. • Each carries out particular tasks. • Many are involved with the synthesis, packaging and transportation of proteins. • Proteins - essential to the everyday functioning of a cell.

5. Cell Wall (ONLY PLANTS) • The cell wall is a tough, rigid structure found outside the cell membrane. • Its main function is to provide support for the plant cell and protection for the cell organelles. • The cell wall is often made up of cellulose.

6. Cell Wall cell wall

7. Cell Membrane • A thin barrier that separates the cytoplasm of a cell with the external environment. • It is selectively permeable • Controls the movement of materials into and out of the cell.

8. Cell Membrane cell membrane

9. Ribosomes • Tiny structures that are found floating in the cytoplasm or attached to the endoplasmic reticulum. • Manufacture of proteins.

10. Ribosomes on the Endoplasmic Reticululm ribosomes

11. Endoplasmic Reticulum • Anetwork of membrane-covered channels used in the transportation of materials within the cell. • Connected to the nucleus, and often contains ribosomes

12. Endoplasmic Reticulum endoplasmic reticulum

13. Golgi Body and Vesicles • Golgi Body packages proteins (into vesicles) for transportation out of the cell. • Vesicles are membrane-covered sacs that store materials (such as proteins). • Materials are often transported into and out of a cell in vesicles.

14. Golgi Body and Vesicles vesicles Golgi body

15. The Nucleus • The most visible part of the cell. • Its main function is to control all cell activities and processes. • The nucleus is bound by a membrane. • Visible within the nucleus is a structure called the nucleolus. Nuclear Pores • Small holes in the nuclear membrane that allow materials (such as ribosomes) in and out of the nucleus

16. Nucleolus • Appears as a darker region within the nucleus. • Site of ribosome synthesis (production) • The nucleolus is not bound by a membrane.

17. Nucleus (liver cell) cytoplasm nucleus nucleolus

18. Nuclear Pores on the surface of a nucleus

19. Mitochondria • Membrane bound organelles where energy is released to fuel cell activities. • Powerhouse of the cell – this is where cellular respiration takes place

20. Mitochondrion

21. Chloroplasts (Plant Only) • Site of photosynthesis in a plant cell. • It contains a molecule called chlorophyll that is specialized to trap sunlight for photosynthesis. • Chloroplasts give the plant its green colour.

22. The Chloroplast

23. Vacuoles • Plant cells have a single large vacuole ** • Animals cells tend to have multiple smaller vacuoles. • Store water and other small molecules

24. Vacuole vacuole

25. Cytoplasm and Cytosol • The cytosol is the fluid in which all the organelles “float” • It is composed of water, sugars and proteins, all of which are essential for cell survival. • The cytoplasm is the cytosol + organelles

26. Cytoskeleton • Filaments and tubules – internal structure for the cell • Provide pathways along which organelles can move