1. The Cell Cell Theory/History Structures Transport Differentiation Levels of Organization

2. Robert Hooke English physicist 1665 Saw a slice of cork tree tissue –Tiny chambers –Termed them “cells” (looked like monks’ cells in monastery)

3. Robert Hooke Published his book Micrographia –Contained drawings of cork cells –Used early microscope

4. Anton Van Leeuwenhoek Dutch businessman 1674 Perfected microscope (about 300x) Saw living things in pond water –“Animalcules” –Observed bacteria (on wood teeth) and protozoa

5. Matthias Schleiden German botanist 1838 Concludes that all plants are made up of cells

6. Theodor Schwann German zoologist 1839 Concluded that all animals are made up of cells

7. Rudolph Virchow German physician/pathologist 1855 Worked with eggs from various organisms Proposes that all cells come from existing cells

8. Cell Theory All living things are composed of cells. Cells are the basic units of structure and function in living things. New cells are produced from existing cells.

9. Janet Plowe 1931 Demonstrates that the cell membrane is a physical structure, not an interface between two liquids.

10. Lynn Margulis 1970 Proposes a theory that certain organelles were once free-living cells themselves

11. Singer - Nicholson 1972 Fluid Mosaic Model –Membranes are phospholipid bilayers with globular proteins embedded in them –Membrane is always moving –Made up of smaller pieces (mosaic)

12. Prokaryote cells  Very simple (bacteria)

13. Eukarote cells  Larger, complex

14. Cell Structures

15. Barriers…  Cell Wall Plants & prok. (not animals) Structural (plant support) & protective role Cellulose Freely permeable

16. Cell walls of onion skin…

17. Barriers…  Cell Membrane (plasma membrane) In ALL cells Support/protection Regulates movement in/out of: ○ Water ○ Nutrients ○ Waste products

18. Cell Membrane...

19. Barriers…  Nuclear Envelope (nuclear membrane) Surrounds nucleus Thousands of pores ○ Material move in/out, incl. RNA

20. Nuclear envelope

21. Fluids…  Cytoplasm (cytosol) Bet. cell mem. and nuclear env., site of most chemical activity  Nucleoplasm Semi-fluid medium of nucleus  Protoplasm Term used for all substances inside cell

22. The Nucleus

23. The Nucleus…  Controls most cell processes  Contains Chromatin DNA bound to proteins During cell division, condenses to Chromosomes…  Has a Nucleolus Small, dense region Assembly of Ribosomes  Nuclear Envelope (or membrane)

25. Organelles of the cytoplasm

26. Cytoskeleton…  Protein filaments  Maintains cell shape  Involved in cell movement

27. Cytoskeleton

28. Ribosomes…  Small,made of RNA  Assembly of proteins  Free in cytoplasm or att. to ER

29. Endoplasmic Reticulum…  Called “ER”  Two types: Rough ER ○ Ribosomes stud surface ○ Aids in synthesis and modif. of proteins ○ Found wrapped around nucleus Smooth ER ○ No ribosomes ○ Special tasks with certain enzymes (such as making lipids)

31. Mitochondrion…  Uses energy from food  Makes high-energy compounds (ATP) needed for Rx elsewhere.  The POWERHOUSE of the cell

33. Golgi Apparatus…  Receives proteins from rough ER  Enzymes attach carbs and lipids to the proteins  Can store proteins until needed  Proteins then sent to final destination  PACKAGING and SHIPPING

34. Golgi Apparatus

35. Vacuoles…  Saclike structure  Stores water, salts, proteins, carbs  Can be large in plant cells Helps in plant support by keeping turgor pressure high

36. Vacuoles

37. Korotnovella, an amoeba. Inside this cell we can see a nucleus near the center with a rather angular dark nucleolus, various food vacuoles, and a clear round contractile vacuole at about 10 o'clock.

38. Lysosomes…  Filled with enzymes  Breaks down lipids, carbs, and proteins from food old organelles debris and harmful invaders

39. Video

40. Plastid 1: Chloroplasts…  In plants, not animals or fungi  Uses sunlight to make energy rich food mol. thru photosynthesis

41. Chloroplasts…

42. Chloroplast

43. Plastid 2: Leucoplast  Sometimes called amyloplast; stores starch (amylose = starch)

44. Plastid 3: Chromoplast SStores pigments in plants

45. Centrioles  Cylindrical; group of microtubules  In animal cells, used in cell division  As “basal bodies,” form cilia and flagella

47. The Cell Membrane  Is composed of a phospholipid bilayer  A barrier; reg. what passes in/out  Supports and protects  Selectively permeable – only certain things pass through.  About 5 nanometers thick (1 nm = 1 Billionth of a meter)

48. Cell membrane - Structure  A phospholipid contains- one head; negatively charged phosphate group that is hydrophilic (water-loving) two tails of fatty acid chains that are hydrophobic (water fearing)

51. Cell membrane features  The fluid mosaic model it is fluid in nature allowing cell mobility Scattered in the membrane are various proteins which perform various functions : ○ enzyme activity, ○ cell attachment, ○ communicating with other cells, ○ Trans. of substances in and out

53. Passive transport Diffusion: net movement of sub. (liquid or gas) from an area of higher conc. to area of lower conc. Example: perfume

55. Passive transport Osmosis: diffusion of water across a semi-permeable or selectively perm. membrane. ○ Hypertonic: Solution having a high conc. of solute. ○ Hypotonic: Solution having a low conc. of solute. ○ Isotonic: Both solutions have equal solute conc. ○ This difference (Δ) of conc. of molecules across a space is called a Concentration Gradient

58. LysisEquilibriumPlasmolysis Turgid FlaccidPlasmolysis Animal Plant

60. Passive transport  Facilitated diffusion = trans. of materials across membranes by transport proteins

63. Active transport  Active transport - Trans. of molecules against a concentration gradient (from regions of low conc. to regions of high conc.) with the aid of proteins in the cell mem. and energy from ATP

65. Other types of active transport Endocytosis – import of materials into cell by infoldings of the cell membrane. A. phagocytosis – “cell eating”; extensions of the cell membrane surround the food and make a vacuole. Lysosomes then secrete enzymes into vacuole to digest food. B. pinocytosis – “cell drinking”; smaller infoldings allowing droplets of liquid to enter cell.

66. Endocytosis Endocytosis Endocytosis in general

67. Exocytosis – reverse of endocytosis  Dumping of excretions or wastes outside by discharging them from waste vacuoles.  Also can result in secretion of substances (ex: gland cells secreting hormones into the bloodstream)

68. Cell Differentiation And hierarchy of organisms’ tissues

69. Cell differentiation  The process by which unspecialized cells develop into their mature forms and functions  Embryonic Stem Cells Undifferentiated (unspecialized) ○ Totipotent – can develop into ANY type tissue  Adult Stem Cells ○ Pluripotent or multipotent – can develop into certain types of tissues.

75. Levels of organization  Level one = cells -basic unit of life; examples are blood cells ○ Red (RBC, or erythrocytes) ○ White (leukocytes) nerve cells (neurons), bone cells (osteoblasts)

76. Levels of organization  Level two -tissues= Made up of cells that are similar in structure and function and which work together to perform a specific activity  -Humans have 4 basic tissues: connective, epithelial, muscle, and nerve. Connective tissue ○ include bones, ligaments, cartilage, blood, tendons Epithelial tissue- ○ skin, the mucosa, and the serosa (lines body cavities and internal organs) Muscle tissue- ○ skeletal muscle, smooth muscle, and cardiac muscle Nerve tissue- ○ brain, spinal cord, and nerves

80. Levels of organization  LEVEL 3 – Organs -Made up of tissues that work together to perform a specific activity heart, brain, skin, etc.  LEVEL4 - Organ Systems -Groups of two or more organs that work together to perform a specific function for the organism.  The Human body has 11 organ systems - circulatory, digestive, endocrine (hormonal), excretory (urinary), lymphatic (immune), integumentary (skin), muscular, nervous, reproductive, respiratory, and skeletal.

81. Levels of organization  LEVEL 5 - Organisms -Entire living things that can carry out all basic life processes. Meaning they can take in materials, release energy from food, release wastes, grow, respond to the environment, and reproduce.  Usually made up of organ systems, but an organism may be made up of only one cell such as bacteria or protist.  Examples - bacteria, amoeba, mushroom, sunflower, human

82. Cell Regulation  What makes a cell divide? Internal signal: Enzymes produced by cell Ext. signal: like growth factor produced elsewhere When cells packed close, NO division Not packed, division starts  Checkpoints: where stop/go signals reg. division

83. Uncontrolled division  Too many cells form a tumor Disrupts normal cell activity Takes nutrients If one area only: benign If spreading: malignant

84. The staging of a carcinoma has to do with the size of the tumor, and the degree to which it has penetrated. When the tumor is small and has not penetrated the mucosal layer, it is said to be stage I cancer. Stage II tumors are into the muscle wall, and stage III involves nearby lymph nodes. The rare stage IV cancer has spread (metastasized) to remote organs. http://www.nytimes.com/imagepages/2007/08/01/health/adam/19222Stagesofcancer.html