1. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh Edition Solomon Berg Martin Chapter 4 Organization of the Cell

2. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cell theory Cells are the basic living units of organization and function All cells come from other cells Work of Schleiden, Schwann, and Virchow contributed to this theory Each cell is a microcosm of life

3. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Biological size and cell diversity

4. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cell surface area-to-volume ratio Plasma membrane must be large enough relative to cell volume to regulate passage of materials Cell size and shape related to function

5. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cell surface area-to-volume ratio

6. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Microscopes Light microscope, referred to as compound microscope, used by most students Two features determine how clearly an object is viewed –Magnification –Resolution Light microscope has 500 times more resolution than human eye

7. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Special optical mechanisms for light microscopes Bright-field microscopy Phase contrast microscopy Differential-interference-contrast microscopy Fluorescence microscope, including confocal fluorescence microscope

8. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Electron microscope Developed in the 1950s Allows study of the ultrastructure of cells 10,000 times more resolution than human eye

9. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Types of electron microscope Transmission electron microscope Scanning electron microscope

10. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Comparing light and electron microscopy

11. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cell fractionation Used to determine function of organelles Cells broken apart and the resulting cell extract spun in a centrifuge Centrifugal force separates extract –Pellet –Supernatant

12. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cell fractionation

13. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Prokaryotic Bacteria and archaea DNA not enclosed in a nucleus Eukaryotic All other known organisms Highly organized membrane-enclosed organelles –Cytoplasm –Nucleoplasm

14. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Functions of cell membranes Divide cell into compartments, allowing for specialized activities Interacting membranes form endomembrane system Vesicles transport materials between compartments

15. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Diagram of a plant cell

16. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Diagram of an animal cell

17. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell The cell nucleus Contains DNA Bounded by –Nuclear envelope –Double membrane perforated with nuclear pores DNA forms chromatin, which is organized into chromosomes Nucleolus –RNA synthesis and ribosome assembly

18. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell The cell nucleus

19. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Endoplasmic reticulum (ER) Network of folded internal membranes in the cytosol Smooth ER –Site of lipid synthesis –Site of detoxifying enzymes Rough ER –Ribosomes manufacture proteins –Proteins may be moved into the ER lumen

20. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Endoplasmic reticulum (ER)

21. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell

22. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Golgi complex Cisternae that process, sort, and modify proteins In animal cells, Golgi complex also manufactures lysosomes Glycoproteins transported to the cis face Golgi modifies carbohydrates and lipids and packages into vesicles

23. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Golgi complex

24. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Lysosomes break down worn- out cell structures, bacteria, and other substances Peroxisomes Involved in lipid metabolism and detoxification Contain enzymes that produce and degrade hydrogen peroxide

25. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Lysosomes

26. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Mitochondria Sites of aerobic respiration Organelles enclosed by a double membrane Place important role in apoptosis Cristae and matrix contain enzymes for aerobic respiration –Nutrients broken down and energy packaged in ATP –Carbon dioxide and water by-products

27. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Mitochondria

28. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Chloroplasts Plastids that carry out photosynthesis Inner membrane of chloroplast encloses the stroma During photosynthesis, chlorophyll traps light energy Energy converted to chemical energy in ATP

29. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Chloroplast

30. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cellular respiration and photosynthesis

31. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cytoskeleton Internal framework made of –Microtubules –Microfilaments –Intermediate filaments Provides structural support Involved with transport of materials in the cell

32. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell The Cytoskeleton

33. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Cilia and flagella Thin, movable structures that project from cell surface Function in movement Microtubles anchored in cell by basal body

34. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Structure of cilia

35. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Glycocalyx, cell coat formed by polysaccarides extending from plasma membrane Many animal cells also surrounded by an extracellular matrix (ECM) Most bacteria, fungi, and plant cell walls made of carbohydrates

36. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Extracellular matrix

37. Copyright © 2005 Brooks/Cole — Thomson Learning Biology, Seventh EditionCHAPTER 4 Organization of the Cell Plant cell walls