Cell Structure & Function

1. Cell Structure & Function http://koning.ecsu.ctstateu.edu/cell/cell.html

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 preexisting cells through cell division.

3. Definition of Cell A cell is the smallest unit that is capable of performing life functions.

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

5. Two Types of Cells Prokaryotic Eukaryotic

6. Prokaryotic • Do not have structures surrounded by membranes • Few internal structures • One-celled organisms, Bacteria http://library.thinkquest.org/C004535/prokaryotic_cells.html

7. Eukaryotic • Contain organelles surrounded by membranes • Most living organisms Plant Animal http://library.thinkquest.org/C004535/eukaryotic_cells.html

8. “Typical” Animal Cell http://web.jjay.cuny.edu/~acarpi/NSC/images/cell.gif

9. “Typical” Plant Cell http://waynesword.palomar.edu/images/plant3.gif

10. Cell Parts Organelles

11. Surrounding the Cell

12. Cell Membrane • Thin protective outer membrane of cell that controls movement in and out of the cell • Many pores • Holds the inner parts of the cell together • Allows materials to flow in and out of the cell. http://library.thinkquest.org/12413/structures.html

13. Cell Wall • Layer around the outside of a plant cells • Made of stiff material • Supports & protects cells http://library.thinkquest.org/12413/structures.html

14. Inside the Cell

15. Nucleus • Directs cell activities • Separated from cytoplasm by nuclear membrane • Contains genetic material - DNA

16. Nuclear Membrane • Surrounds nucleus • Made of two layers • Openings allow material to enter and leave nucleus http://library.thinkquest.org/12413/structures.html

17. Chromosomes • In nucleus • Made of DNA • Contain instructions for traits & characteristics http://library.thinkquest.org/12413/structures.html

18. Nucleolus • Inside nucleus • Contains RNA to build proteins http://library.thinkquest.org/12413/structures.html

19. Cytoplasm • Gel-like mixture • Surrounded by cell membrane • Fills in the space between the cell membrane and nucleus • Supports the cells other organelles

20. Endoplasmic Reticulum • Web of tubes and pouches that run throughout the cell • Moves materials around in cell • Found “floating” in the cytoplasm between the nucleus and the cell membrane http://library.thinkquest.org/12413/structures.html

21. Ribosomes • Each cell contains thousands • Make proteins • Found on endoplasmic reticulum & floating throughout the cell http://library.thinkquest.org/12413/structures.html

22. Mitochondria • The inner layer has many folds. The energy is converted off the surface of the folds. • Produces energy through chemical reactions – breaking down fats & carbohydrates – turns it into food. • Controls level of water and other materials in cell • Recycles and decomposes proteins, fats, and carbohydrates http://library.thinkquest.org/12413/structures.html

23. Golgi Bodies • Protein 'packaging plant' • Move materials within the cell • Move materials out of the cell http://library.thinkquest.org/12413/structures.html

24. Lysosome • Digestive 'plant' for proteins, fats, and carbohydrates • Transports undigested material to cell membrane for removal • Cell breaks down if lysosome explodes http://library.thinkquest.org/12413/structures.html

25. Vacuoles • Tiny storage sacs • They store food and waste • They can shrink or expand depending on how much material they are holding. • Larger in plant cells • Contains water solution • Help plants maintain shape • Found “floating” in the cytoplasm http://library.thinkquest.org/12413/structures.html

26. Chloroplast • Found only in plant cells • Contains green chlorophyll • Where photosynthesis takes place –(where a plant makes food) • Found in cytoplasm http://library.thinkquest.org/12413/structures.html