Table of Contents

1. Chapter7 Cell Structure and Function Table of Contents Section 1 The History of Cell Biology Section 2 Introduction to Cells Section 3 Cell Organelles and Features Section 4 Unique Features of Plant Cells

2. Section 1 The History of Cell Biology Chapter7 Objectives • Namethe scientists who first observed living and nonliving cells. • Summarizethe research that led to the development of the cell theory. • Statethe three principles of the cell theory. • Explainwhy the cell is considered to be the basic unit of life.

3. Section 1 The History of Cell Biology Chapter7 The Discovery of Cells • All living things are made up of one or more cells. • A cell is the smallest unit that can carry on all of the processes of life.

4. Section 1 The History of Cell Biology Chapter7 The Discovery of Cells, continued • Development of the microscope… • Hooke • Robert Hooke (1665) discovered cells in slices of cork. • “great many boxes” … named them CELLS (monks) • Leeuwenhoek (Lay-vun-hook) • Anton van Leeuwenhoek was the first to observe living cells in microorganisms. • 1673 saw microorganisms using a simple microscope

5. Section 1 The History of Cell Biology Chapter7 The Cell Theory • Observations begun by Hooke/van Leeuwenhoek, with the help of other scientists, helped to create the cell theory. • Approximately 150 years in the making • The cell theory states that all living organisms: • are made of one or more cells • cells are the basic units of structure and function • cells come only from pre-existing cells.

6. Section 1 The History of Cell Biology Chapter7 The Cell Theory, continued • Cellular Basis of Life • All living things • are made of organized parts • obtain energy from their surroundings • perform chemical reactions • change with time • respond to their environment • reproduce

7. Other Scientists… • Matthias Schleiden (botanist) • Concluded all plants are made of cells • Theodor Schwann (zoologist) • Concluded that all animals are made of cells • Rudolph Virchow (physician) • While studying how disease affects living things, reasoned that cells come only from other cells.

8. Section 2 Introduction to Cells Chapter7 Objectives • Explain the relationship between cell shape and cell function. • Identify the factor that limits cell size. • Describethe three basic parts of a cell. • Compareprokaryotic cells and eukaryotic cells. • Analyzethe relationship among cells, tissues, organs, organ systems, and organisms.

9. Section 2 Introduction to Cells Chapter7 Cell Diversity • Cell Shape • A cell’s shape reflects its function.

10. Nerve Cell transmit messages • Skin Cell covering • White Blood Cell part of the immune system

11. Section 2 Introduction to Cells Chapter7 Cell Diversity, Continued • Cell Size • Cell size is limited by a cell’s surface area–to-volume ratio.

12. Cell Diversity… not all cells are alike SIZE • Cells are limited in size by the ratio of their outer surface area to their volume. • If a cell keeps the same shape as it grows, its volume will increase more rapidly than its surface area (SA) • IMPORTANT BECAUSE… • nutrients, oxygen, other materials must enter through its surface • as a cell grows larger, its surface area (SA) becomes too small to allow these materials to enter the cell quickly enough to meet the cell’s needs ***The volume actually grows less rapidly than the SA

13. Section 2 Introduction to Cells Chapter7 Basic Parts of a Cell • The three basic parts of a cell are the plasma membrane (cell membrane), the cytoplasm, and the nucleus.

14. Section 2 Introduction to Cells Chapter7 Basic Parts of a Cell, continued • Plasma Membrane • The cell’s outer boundary, called theplasma membrane(or the cell membrane), covers a cell’s surface and acts as a barrier between the inside and the outside of a cell.

15. Section 2 Introduction to Cells Chapter7 Basic Parts of a Cell, continued • Cytoplasm • The region of the cell that is within the plasma membrane and that includes the fluid (cytosol), the cytoskeleton, and all of the organelles except the nucleus is called thecytoplasm.

16. Section 2 Introduction to Cells Chapter7 Basic Parts of a Cell, continued • Nucleus • The nucleus is a large, membrane-bound organelle that contains a cell’s DNA.

17. Section 2 Introduction to Cells Chapter7 Two Basic Types of Cells • Prokaryotes • Prokaryote cellslack a nucleus and membrane-bound organelles. • Unicellular • Remember: • Pro… NO! 

18. Section 2 Introduction to Cells Chapter7 Two Basic Types of Cells, continued • Eukaryotes • Eukaryote cells have a true nucleus (membrane-bound) and membrane-bound organelles. • The difference between prokaryotes and eukaryotes is very important – separate kingdoms!

19. Section 2 Introduction to Cells Chapter7 Cellular Organization – heirarchy… • In multicellular eukaryotes, cells organize into tissues, organs, organ systems, and finally organisms.

20. Section 3 Cell Organelles and Features Chapter7 Objectives • Describethe structure and function of a cell’s plasma membrane. • Summarize the role of the nucleus. • Listthe major organelles found in the cytosol, and describe their roles. • Identifythe characteristics of mitochondria. • Describe the structure and function of the cytoskeleton.

21. Section 3 Cell Organelles and Features Chapter7 Plasma Membrane • Membrane Lipids • Cell membranes consist of aphospholipid bilayer.

22. Section 3 Cell Organelles and Features Chapter7 Structure of Lipid Bilayer

23. Section 3 Cell Organelles and Features Chapter7 Plasma Membrane, continued • Membrane Proteins • Cell membranes often contain proteins embedded within the phospholipid bilayer.

24. Plasma Membrane, cont’d…

25. Section 3 Cell Organelles and Features Chapter7 Plasma Membrane, continued • Fluid Mosaic Model • Thefluid mosaic modelstates that the phospholipid bilayer behaves like a fluid more than it behaves like a solid. • *Think about a sheet of marbles… how would a sheet of marbles move? • Where does the term mosaic come from? • Think of artwork…

26. Fluid Mosaic Model

27. Section 3 Cell Organelles and Features Chapter7 Nucleus • The nucleusdirects the cell’s activities and stores DNA.

28. Section 3 Cell Organelles and Features Chapter7 Nucleus of a Cell

29. Section 3 Cell Organelles and Features Chapter7 Nucleus, continued • Nuclear Envelope • The nucleus is surrounded by a double membrane called the nuclear envelope.

30. Section 3 Cell Organelles and Features Chapter7 Nucleus, continued • Nucleolus • The nucleolus is the place where DNA is concentrated when it is in the process of making ribosomal RNA.

31. Section 3 Cell Organelles and Features Chapter7 Mitochondria • Mitochondriaharvest energy from organic compounds and transfer it to ATP.

32. Section 3 Cell Organelles and Features Chapter7 Ribosomes • Ribosomesare either free or attached to the rough ER and play a role in protein synthesis.

33. Section 3 Cell Organelles and Features Chapter7 Endoplasmic Reticulum • The rough ER prepares proteins for export or insertion into the cell membrane.

34. Section 3 Cell Organelles and Features Chapter7 Endoplasmic Reticulum, continued • The smooth ER builds lipids and participates in detoxification of toxins.

35. Section 3 Cell Organelles and Features Chapter7 Golgi Apparatus • TheGolgi apparatusprocesses and packages proteins.

36. Section 3 Cell Organelles and Features Chapter7 Vesicles • Vesicles, including lysosomes (digestive enzymes) and peroxisomes (detoxification enzymes), are classified by their contents.

37. Section 3 Cell Organelles and Features Chapter7 Vesicles, continued • Protein Synthesis • The rough ER, Golgi apparatus, and vesicles work together to transport proteins to their destinations inside and outside the cell.

38. Section 3 Cell Organelles and Features Chapter7 Processing of Proteins

39. Section 3 Cell Organelles and Features Chapter7 Cytoskeleton • The cytoskeleton is made of protein fibers that help cells move and maintain their shape. • The cytoskeleton includes microtubules, microfilaments, and intermediate filaments.

40. Section 3 Cell Organelles and Features Chapter7 Cytoskeleton, continued • Cilia and Flagella • Ciliaandflagellaare hairlike structures that extend from the surface of the cell, where they assist in movement.

41. Section 3 Cell Organelles and Features Chapter7 Cytoskeleton, continued • Centrioles • Centriolesconsist of two short cylinders of microtubules at right angles to each other and are involved in cell division.

42. Section 4 Unique Features of Plant Cells Chapter7 Objectives • Listthree structures that are present in plant cells but not in animal cells. • Comparethe plasma membrane,the primary cell wall, and the secondary cell wall. • Explainthe role of the central vacuole. • Describethe roles of plastids in the life of a plant. • Identifyfeatures that distinguish prokaryotes, eukaryotes, plant cells, and animal cells.

43. Section 4 Unique Features of Plant Cells Chapter7 Plant Cells • Plant cells have cell walls, central vacuoles, and plastids.

44. Section 4 Unique Features of Plant Cells Chapter7 Cell Wall • In plant cells, a rigidcell wallcovers the cell membrane and provides support and protection.

45. Section 4 Unique Features of Plant Cells Chapter7 Central Vacuole • Largecentral vacuolesstore water, enzymes, and waste products and provide support for plant tissue.

46. Section 4 Unique Features of Plant Cells Chapter7 Plastids • Plastidsstore starch and pigments. • The chloroplast converts light energy into chemical energy by photosynthesis.

47. Section 4 Unique Features of Plant Cells Chapter7 Comparing Cells • Prokaryotes, animal cells, and plant cells can be distinguished from each other by their unique features.

48. Section 4 Unique Features of Plant Cells Chapter7 Comparing Plant and Animal Cells