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Cell Biology

Cell Biology. www.edumedia-sciences.com/recherche.php?q=Cell. Robert Hooke (1665) English scientist

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Cell Biology

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  1. Cell Biology www.edumedia-sciences.com/recherche.php?q=Cell

  2. Robert Hooke (1665) English scientist looked at a thin slice of cork through a compound microscope observed tiny, hollow, room like structures called these structures 'cells' because they reminded him of the rooms that monks lived in.He only saw the outer walls (cell walls) because cork cells are not alive ( dead cells)

  3. Anton van Leeuwenhoek Dutch scientist looked at blood, rainwater, scrapings from teeth through a e microscope. He observed living cells; called some 'animalcules' some of the small 'animalcules' are now called bacteria

  4. Matthias Schleiden (1838) German botanist viewed plant parts under a microscope discovered that plant parts are made of cells. Theodor Schwann (1839) German zoologist viewed animal parts under a microscope discovered that animal parts are made of cells Rudolph Virchow (1855) German physician stated that all living cells come only from other living cells

  5. CELL THEORY1. ALL LIVING THINGS ARE COMPOSED OF CELLS         2. CELLS ARE THE BASIC UNIT OF STRUCTURE AND FUNCTION IN LIVING THINGS         3.ALL CELLS ARE PRODUCED FROM OTHER CELLS.

  6. Theodor Schwann All animals are made of cells

  7. Matthias Schleiden All plants are made of cells.

  8. SPONTANEOUS GENERATION- an UNTRUE THEORY stating that living things arise from nonliving sources FRANCESCO REDI  in the 1600’S DISPROVED THIS IDEA Rudolph Virchow all living cells come only from other living cells

  9. NERVE CELLS Muscle cells Skin Cells

  10. Why do cells divide. A cell divides so as to maintain a favourable Surface area to volume ratio.A cell receives food and oxygen and turns out waste materials through it's membrane. A cell membrane of specific area can serve the contents ofa particular volume only.Increase in the volume increases the requirements of the cell and this increases the need for greater membrane area.Now,the Surface area of a sphere increase as the square of the radius and the volume of a sphere increases as the cube of the radius or to say, in simpler words,the volume of the cell increase more rapidly then the area of its membrane.Hence, as a cell grows,it's membrane in due course of time becomes insufficient to move the required amount of substances in and out. The cell by dividing has a more favourable surface area to volume ratio. Thus, the cell divide so as to maintain it's size such that all it's requirements ofnutrition,respiration and excretion are met. • http://plaza.ufl.edu/alallen/pgl/modules/rio/stingarees/module/why.html

  11. Colonial Organisms

  12. The little stars we can see on the image of the stone are the colonial Tunicates.

  13. Membranipora.

  14. The Structure and Function of the Cell Membrane telstar.ote.cmu.edu/.../membranes/index.html http://www.ibiblio.org/virtualcell/textbook/chapter3/chapter3.htm

  15. A Phosphlipid

  16. A lipid bilayer http://telstar.ote.cmu.edu/biology/downloads/membranes/index.htm l

  17. http://www.wisc-online.com/objects/index_tj.asp?objID=ap1101 http://www.bio.davidson.edu/people/macampbell/111/memb-swf/membranes.swf http://www.susanahalpine.com/anim/Life/memb.htm

  18. We will group the organelles into three catagories:

  19. Nucleus cytoplasm Endoplasmic reticulum Ribosomes Golgi apparatus Mitochondria Lysosome Cytoskeleton Vacuoles Cilia and Flagella Centrioles Comparing animal and plant cells

  20. Nucleus cytoplasm Endoplasmic reticulum Ribosomes Golgi apparatus Mitochondria Lysosome Cytoskeleton Vacuoles Cilia and Flagella Centrioles The Cell Wall Central Vacuole Plastidschloroplasts Anatomy of the Plant Cell Comparing animal and plant cells

  21. The Nucleus http://www.ibiblio.org/virtualcell/textbook/chapter3/chapter3.htm The Cell

  22. One or more per cell - Spherical shape - Denser than surrounding cytoplasm Chromosomes- Usually in the form of chromatin- Contains genetic information- Composed of DNA- Thicken for cellular division- Set number per species (i.e. 23 pairs for human) Nuclear membrane- Surrounds nucleus- Composed of two layers- Numerous openings for nuclear traffic Nucleolus- Spherical shape- Visible when cell is not dividing- Contains RNA for protein manufacture The Cell

  23. cytoplasm Collective term for cytosol and organelles contained within Colloidal suspension Cytosol mainly composed of water with free-floating molecules Viscosity constantly changes We will group the organelles into three categories: Group 1 - Those organelles involved in protein production Group 2 - Those organelles involved in energy production Group 3 - Specialty organelles The Cell

  24. Endoplasmic reticulum- Tubular network fused to nuclear membrane- Goes through cytoplasm onto cell membrane- Stores, separates, and serves as cell's transport system- Smooth type: lacks ribosomes- Rough type (pictured): ribosomes embedded in surface The Cell

  25. The Cell

  26. The Cell

  27. Ribosomes- Each cell contains thousands- Act as 'protein factories'- Composes 25% of cell's mass- Stationary type(Attached): embedded in rough endoplasmic reticulum, produces proteins to be secreted from the cell. - Mobile type( free): injects proteins directly into cytoplasm, produces proteins to be consumed in the cell. The Cell

  28. Mitochondria- Second largest organelle with unique genetic structure- Double-layered outer membrane with inner folds called cristae- Produce Energy in the form of ATP through chemical reactions take place on cristae through a process called oxidative phosphorylation. This process uses oxygen and simple sugars to create adenosine triphosphate (ATP), the cell’s main energy source. - Controls level of water and other materials in cell- Recycles and decomposes proteins, fats, and carbohydrates, and forms urea - Although most DNA is packaged in chromosomes within the nucleus, mitochondria also have a small amount of their own DNA. This genetic material is known as mitochondrial DNA or mtDNA. mitochondria originate only from other mitochondria. - for the origin of mitochondria (and chloroplasts) suggests that mitochondria are descended from specialized bacteria that became part of the cytoplasm of another cell. The ability of symbiont bacteria to conduct cellular respiration in host cells that relied on glycosis and fermentation would have provided a considerable evolutionary advantage. Similarly, host cells with symbiont bacteria capable of photosynthesis would also have an advantage. In both cases, the number of environments in which the cells could survive would have been greatly expanded. The Cell

  29. The Cell

  30. Golgi apparatus- Protein 'packaging plant'- A membrane structure found near nucleus- Composed of numerous layers forming a sac http://bcs.whfreeman.com/thelifewire/content/chp04/0402002.html The Cell

  31. Lysosome- originating in part from the Golgi apparatus • contain digestive enzymes • sites for the breakdown of food and foreign objects taken up by the cell. • - Digestive 'plant' for proteins, lipids, and carbohydrates- Transports undigested material to cell membrane for removal- Vary in shape depending on process being carried out- Cell breaks down if lysosome explodes The Cell

  32. Peroxisomes function to rid the cell of toxic substances, in particular, hydrogen peroxide -- a common byproduct of cellular metabolism. These organelles contain enzymes that convert the hydrogen peroxide to water, rendering the potentially toxic substance safe for release back into the cell. Some types of peroxisomes, such as those in liver cells, detoxify alcohol and other harmful compounds by transferring hydrogen from the poisons to molecules of oxygen. Glyoxysomes They are small bodies usually located near the mitochondria.They help to convert stored lipids (oils) into energy for the developing plant embryo. The Cell

  33. Vacuoles- Membrane-bound sacs for storage, digestion, and waste removal- Contains water solution- Contractile vacuoles for water removal (in unicellular organisms) The Cell

  34. Cytoskeleton- The cytoplasm contains a fine network of fibrous protein elements that form a framework for supporting the extensively branched membranes found in the relatively fluid cytoplasmic matrix. - Supports cell and provides shape. - composed of three types of organelles microtubules, microfilaments and microbodies. - Aids movement of materials in and out of cells. The Cell

  35. The Cell

  36. Cilia and Flagella • Whiplike appendages extend from the surface of many types of eukaryotic cells. • If there are many of them, they are called cilia; if only one, or a few, they are flagella. • Flagella also tend to be longer than cilia but are otherwise similar in construction. • Cilia and flagella move liquid past the surface of the cell. • For single cells, such as sperm, this enables them to swim. • For cells anchored in a tissue, like the epithelial cells lining our air passages, this moves liquid over the surface of the cell (e.g., driving particle-laden mucus toward the throat). • Structure of Cilia and Flagella The Cell

  37. Structure of Cilia and Flagella • Both cilia and flagella consist of: • a cylindrical of 9 pair of microtubules and a pair of single microtubules running up through the center of the bundle,. • The entire assembly is sheathed in a membrane that is an extension of the plasma membrane. Cilia and Flagella

  38. Cilia and Flagella Cilia and Flagella

  39. trachea Cilia and Flagella

  40. Cilia and Flagella

  41. Cilia and Flagella

  42. Centrioles are cylindrical structures that are composed of groupings of microtubules arranged in a 9 + 3 pattern. The pattern is so named because a ring of nine microtubule "triplets" are arranged at right angles to one another. Centrioles are found in animal cells and play a role in cell division. The Cell

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