1 / 85

The Cell

The Cell. Cell Theory/History Structures Transport Differentiation Levels of Organization. Robert Hooke. English physicist 1665 Saw a slice of cork tree tissue Tiny chambers Termed them “cells” (looked like monks’ cells in monastery). Robert Hooke. Published his book Micrographia

uma
Télécharger la présentation

The Cell

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Cell Cell Theory/HistoryStructuresTransport 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 The Control Center

  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)

  24. Organelles of the cytoplasm Little Organsassist the cell in conducting reproductive, respiratory, and structural needs

  25. Cytoskeleton… • Protein filaments • Maintains cell shape • Involved in cell movement

  26. Cytoskeleton

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

  28. 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)

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

  30. 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

  31. Golgi Apparatus

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

  33. Vacuoles

  34. Vacuoles 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.

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

  36. Video

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

  38. Chloroplasts…

  39. Chloroplast

  40. Plastid 2: Leucoplast • Sometimes called amyloplast; stores starch (amylose = starch)

  41. Plastid 3: Chromoplast • Stores pigments in plants

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

  43. 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)

  44. 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)

More Related