2. 1 Cell Structure & Function

3. Cells Cells are the basic units of life. It is important to note that each cell in your body is alive all on its own. The cell theory (which you should have learned about in grade 8), states 3 very important things that we need to be familiar with: 2

4. Cell Theory 1.All living things are composed of cells. 2.Cells are the basic units of structure and function in living things. 3.All cells are produced from other cells. 3

5. Basic Structure of a Cell 4

6. First to View Cells In 1665, Robert Hooke used a microscope to examine a thin slice of cork (dead plant cells) What he saw looked like small boxes 5

7. First to View Cells Hooke is responsible for naming cells Hooke called them “CELLS” because they looked like the small rooms that monks lived in called Cells 6

8. Anton van Leeuwenhoek In 1674, Leeuwenhoek (a Dutch microscope maker), was first to view organisms (living things) Leeuwenhoek used a simple, handheld microscope to view pond water & scrapings from his teeth 7

9. History of Cells & the Cell Theory 8 Virchow Cell Specialization

10. Introduction to Cells Cells are the basic units of organisms Basic types of cells: 9 Animal CellPlant Cell Bacterial Cell

11. Number of Cells 10 Organisms may be: Unicellular – composed of one cell Multicellular- composed of many cells that may organize

12. 11 Cells May be Prokaryotic or Eukaryotic  Prokaryotes include bacteria & lack a nucleus or membrane-bound structures called organelles  Eukaryotes include most other cells & have a nucleus and membrane- bound organelles (plants, fungi, & animals)

13. Prokaryotes 12 Nucleoid region contains the DNA Cell membrane & cell wall Contain ribosomes (no membrane) to make proteins in their cytoplasm

14. Eukaryotic Cell Contain 3 basic cell structures: Nucleus Cell Membrane Cytoplasm with organelles 13

15. Two Main Types of Eukaryotic Cells 14 Plant Cell Animal Cell

16. Organelles Very small size Can only be observed under a microscope Have specific functions Found throughout cytoplasm 15

17. Control Organelle 16 Controls the normal activities of the cell Contain the DNA Bounded by a nuclear membrane Contains chromosomes Nucleus

18. More on the Nucleus 17 Each cell has fixed number of chromosomes that carry genes Genes control cell characteristics Nucleus

19. Golgi Bodies Stacks of flattened sacsStacks of flattened sacs Have a shipping side & a receiving sideHave a shipping side & a receiving side Receive & modify proteins made by ERReceive & modify proteins made by ER Transport vesicles with modified proteins pinch off the endsTransport vesicles with modified proteins pinch off the ends 18 Transport vesicle

20. Lysosome Contain digestive enzymesContain digestive enzymes Break down food and worn out cell parts for cellsBreak down food and worn out cell parts for cells Programmed for cell death (lyse & release enzymes to break down & recycle cell parts)Programmed for cell death (lyse & release enzymes to break down & recycle cell parts) 19

21. Nucleolus Cell may have 1 to 3 nucleoli Cell may have 1 to 3 nucleoli Inside nucleusInside nucleus Disappears when cell dividesDisappears when cell divides Makes ribosomes that make proteinsMakes ribosomes that make proteins 20

22. Smooth & Rough Endoplasmic Reticulum 21 Smooth ER lacks ribosomes & makes proteins USED In the cell Rough ER has ribosomes on its surface & makes proteins to EXPORT

23. Cell Powerhouse 22 Rod shape Site of Cellular respiration Mitochondrion ( mitochondria )

24. In Animal Cells: 23 Active cells like muscles have more mitochondria Burn sugars to produce energy ATP Mitochondria

25. Surrounding the Cell 24 Lies immediately against the cell wall in plant cells Made of protein and phospholipids Selectively permeable Cell membrane

26. Cell or Plasma Membrane 25 Living layer Controls the movement of materials into and out of the cell Selectively permeable Cell membrane

27. Cell Wall 26 Nonliving layer Gives structure and shape to plant and bacterial cells Cell wall

28. Cytoplasm of a Cell 27 Jelly-like substance enclosed by cell membrane Provides a medium for chemical reactions to take place Cytoplasm

29. More on Cytoplasm 28 Contains organelles to carry out specific jobs Examples: chloroplast & mitochondrion Cytoplasm

30. Plant Cell Organelles 29 Contain the green pigment chlorophyll Traps sunlight to make to make sugars (food) Process called photosynthesis Chloroplast

31. Plant Cell 30 Dead layer Large empty spaces present between cellulose fibers Freely permeable Cell wall

32. Plant Cell Made of cellulose which forms very thin fibers Strong and rigid Found in plant cells 31 Cell wall

33. Plant Cell 32 Protect and support the enclosed substances (protoplasm) Resist entry of excess water into the cell Give shape to the cell Cell wall

34. Plant Cell Organelles 33 Have a large central vacuole Surrounded by tonoplast Contains cell sap Sugars, proteins, minerals, wastes, & pigments Vacuole

35. Different kinds of plant cells 34 Onion Epidermal Cells Root Hair Cell root hair Guard Cells

36. Animal cell 35 mitochondrion nucleus glycogen granule cell membrane cytoplasm No cell wall or chloroplast Stores glycogen in the cytoplasm for food energy vacuole

37. Animal Cell Organelles Near the nucleus Paired structures Help cell divide 36

38. Different kinds of animal cells 37 white blood cell red blood cell cheek cells sperm nerve cell muscle cell Amoeba Paramecium

39. Similarities between plant cells and animal cells Both have a cell membrane surrounding the cytoplasm 38 Both have a nucleus Both contain mitochondria

40. Differences between plant cells and animal cells 39 Animal cellsPlant cells Relatively smaller in size Irregular shape No cell wall Relatively larger in size Regular shape Cell wall present

41. Differences between Plant Cells and Animal Cells 40 Animal cellsPlant cells Vacuole small or absent Glycogen as food storage Nucleus at the center Large central vacuole Starch as food storage Nucleus near cell wall