Cell Structures, Functions and Transport

1. Cell Structures, Functions and Transport

2. Discovery of the cell A. Early Scientists • 1665- Robert Hooke Discovered cell and named it • Looking at thin slice of cork • Coined the term “cells”

3. Early Scientists • 1673- Anton van Leeuwenhoek • First to see living cells in microscope Green algae- Spyrogyra Pond protist- Vorticella

4. A. Early Scientists • 1838-1855 Matthias Schleiden, Teodor Schwann, Rudolf Virchow • Developed and defined Cell theory

5. B. Cell Theory • All living things are composed of one or more cells • Cells are the basic unit • Cells can only come from other cells

6. C. Cell Diversity • Size (Fig 4-1 pg 70) • Limited by surface to volume ratio • Volume increases more rapidly than surface and the cell is unable to function

7. C. Cell Diversity • Shape (figure 4.2 pg 71) • Determined by function • Example: Nerve, skin, WBC

8. C. Cell Diversity • Internal Organization • Organelles are “tiny organs” that perform a specific function for the cell

9. C. Cell Diversity • Eukaryotes contain membrane bound nucleus • Prokaryotes do not contain membrane bound nucleus (bacteria)

10. Parts and functions of the Eukaryotic cell • See pg 74 in your book

11. Overview of the whole cell

13. A. Cell Membrane • Selectively Permeable = controls passage of substances in/out of the cell • Composed mainly of lipids and proteins

14. Membrane lipids are phospholipids in two layers (grey “popsicles” in picture) • Hydrophilic head towards the outside • Hydrophobic tail turned to the inside

15. Steroids fit between the tails of the phospholipid layer (cholesterol-yellow molecules in picture)

16. Membrane proteins (large purple molecules in picture) • Peripheral Proteins • Attach to exterior/interior surface of the cell membrane • Hold the desired molecules in place • Integral Protein • Transports the desired molecule through a channel • Transports to the external or internal part of the cell

17. e.Fluid Mosaic Model- Dynamic model and not static- protein channels will move as needed Figure 3.3

18. B. Organelles (use table 4.2 pg 75 and figure 4.7 pg 76) • Cytoplasm holds organelles in place and cytosol bathes the organelles with salts, mineral and organic molecules

20. Eukaryotic Cell Organelles and Function • Mitochondria- Nickname: “The Powerhouse” • Function: Energy formation • Breaks down food to make ATP • ATP: is the major fuel for all cell activities that require energy • Cristae: Inner membrane, increases surface for ATP production • Mitochondrial DNA Inheriance from the mother, not father

23. Figure 7-5 Plant and Animal Cells Animal Cell Section 7-2 Cytoplasm Nucleolus Ribosomes Nucleus Cell Membrane Go to Section:

24. Eukaryotic Cell Organelles and Function • Ribosomes • Function: synthesis of proteins • Composed of Protein and RNA (rRNA) • Some attached to Endoplasmic Reticulum (ER) • Found in all cells, prokaryotic and eukaryotic

25. Eukaryotic Cell Organelles and Function • Endoplasmic Reticulum (ER)--Nickname: “Roads” • Function: The internal delivery system of the cell

26. Endoplasmic Reticulum • 2 Types: • Rough ER: • Rough appearance because it has ribosomes • Function: helps make proteins, that’s why it has ribosomes • Smooth ER: • NO ribosomes • Function: makes fats or lipids

27. Figure 3.19

29. Figure 7-5 Plant and Animal Cells Animal Cell Section 7-2 Cytoplasm Ribosomes Nucleolus Nucleus Cell Membrane Smooth Endoplasmic Reticulum Rough Endoplasmic Reticulum Golgi Complex Go to Section:

30. Eukaryotic Cell Organelles and Function • Golgi Complex--Nickname: The packaging plant and shippers • Function: packages, modifies, and transports materials to different location inside/outside of the cell (secretions) • Modifies the protein for its final destination

34. Eukaryotic Cell Organelles and Function • Lysosomes: circular, but bigger than ribosomes)--Nickname: “Clean-up Crews” • Function: • contains hydrolytic or digestive enzymes • breaks down food into particles the rest of the cell can use • destroys old cells

36. Cytoskeleton

37. Eukaryotic Cell Organelles and Function • Cytoskeleton • Function: • Movement of organelles • Support of cell • Composed of • Microfilaments (actin and myosin – muscles!) • Microtubules (Cell Division)

40. and cilia

41. Eukaryotic Cell Organelles and Function • Cilia and Flagella • Function: Assist in Movement • Cilia moves material and the cell • Flagella moves the cell • Composed of microtubules

45. Eukaryotic Cell Organelles and Function • Nucleus--Nickname: “The Control Center” • Functions: • Stores the DNA as the chromatin • “Directions” for making proteins • Nucleolus: dark spot in the middle of the nucleus that helps make ribosomes

46. Cytoplasm Smooth ER Vacuole Ribosomes Chloroplasts Cell Membrane Cell Wall Nucleolus Golgi Bodies Nucleus Mitochondria Rough ER C. Plant Cells (figure 4.15) • Have all structures of Eukaryotic cells (1-9)

47. Cytoplasm Smooth ER Vacuole Ribosomes Chloroplasts Cell Membrane Cell Wall Nucleolus Golgi Bodies Nucleus Mitochondria Rough ER

48. C. Plant Cells (figure 4.15) • Cell Wall- Primary and Secondary layer • Function: provides support and protection to the cell membrane • Contains cellulose – a complex carbohydrate

49. Cytoplasm Smooth ER Vacuole Ribosomes Chloroplasts Cell Membrane Cell Wall Nucleolus Golgi Bodies Nucleus Mitochondria Rough ER Plant Cells (figure 4.15)

50. C. Plant Cells (figure 4.15) • Vacuoles • Function: stores water • This is what makes lettuce crisp • When there is no water, the plant wilts • Store enzymes and metabolic wastes • Vacules may be 90% of the cell size