Chapter Three

  1. Plasma Membrane
    • * Barrier to cell contents
    • * Double layered
    • * Embedded with proteins, Cholesterol, and Glycoproteins
    • * Flexible and elastic
    • * Selective permeability
    • * Small molecules such as oxygen and carbon dioxide can pass freely [some move through lipids]
    • * Water soluble molecules such as amino acids, sugars, and ions can not pass [some move through protein]
    • * Proteins embedded within the membrane functions as channels to allow water soluble molecule to pass through
    • * Proteins act as hormone receptors
    • * Glycoproteins act as cell markers
  2. Phospholipid Bilayer
    • * Polar Head
    • o Hydrophilic
    • * Soluble in water
    • * Non-polar Head
    • o Hyrophobic
    • * Insoluble in water
  3. Golgi Apparatus
    • * Composed of flattend membranous sac
    • * Modifies, packages and ships proteins
    • * Proteins are shipped in vesicles to various location in the cell
  4. Smooth Endoplasmic Reticulum
    • * Lacks Ribosomes
    • * Contains enzymes important for lipid synthesis
    • * Important in metabolism of drugs and alcohol
    • [allows cells to make lipids]
  5. Rough Endoplasmic Reticulum
    • * Membrane-bounded flatten sacs
    • * Fluid filled vesicles
    • * Functions in protein synthesis
    • * Attached to nucleus
    • * Studded with ribosomes [appears rough]
    • * Ribosomes may exist freely in the cytoplasm to synthesis protein
    • * Ribosomes are made of RNA and protein
  6. Cytoplasm
    • * The inside of the cell
    • * Contains network of organelles suspended in clear liquid called Cytosol
    • * This is where nutrients are received and processed
  7. Mitochondria
    • * Elongated fluid filled sacs
    • * Double membrane
    • * Extensive folding of inner membrane
    • * Produce energy molecule (ATP)
  8. Cytoskeleton
    • * Thin strands in the cytoplasm called microfilaments
    • * Microfilaments
    • o Tiny rods of actin proteins
    • o Provide cell motility
    • o Abundant in muscle cells
    • * Microtubules
    • o Long slender tubes with big diameter
    • o Strength and movement of material within the cell
    • [i.e. a structure of a house]
  9. Cells
    • * 75 trillion cells that make the human body
    • * ~200 different cells
    • * Vary greatly in size and shape
    • * All cells exhibit various structures known as organelles, that allow them to function and survive
    • * Cells must carry chemical reactions to survive
  10. Additional organelles
    • Lysosomes
    • o Tiny membrane sac
    • o Contains enzyames to breakdown nutrient or foreign particles
    • o Garbage disposal cell
  11. Additional organelles
    • Peroxisomes
    • o Membranous sac are abundant in liver and kidney cells
    • o Contains enzynes to speed uo chemical reaction
    • o Detoxification of alcohol
  12. Additional organelles
    • Centrosome
    • o Consists of two hollow cylinders called centroles
    • o Important function in cell division
    • [helps mitosis]
  13. Nucleus
    • * Houses the genetic material (DNA)
    • * Double layer Nuclear Membrane
    • * Membrane contains nuclear pores
    • * Nucleoplasm the inside of the nucleus contains
    • o A nucleolus where ribosomes are synthesized
    • o Chromatin which is made of DNA and proteins
  14. Cilia & Flagella
    • * Made of microtubles
    • * Cilia (hair like structure)
    • o Move fluid on surface of cells
  15. Flagella
    • o Allows cells to move
    • [sperm cells]
  16. How can cells survive?
    • * Water: most abundant chemical in the body
    • * Food used as energy source
    • * Oxygen to drive metabolic process
  17. Membrane Transport
    • * Is the movement of substances in and out of the cell
    • * There are two basic methods
    • o Passive transport that does not require energy
    • o Active transports that required the use of energy
  18. Passive transport
    • Simple diffusion
    • Through the lipid
    • Facilitated diffusion
    • Through the Protein
    • Osmsis
    • Diffusion of water
  19. Chemical terminology
    • Water
    • Solvent
    • Sugar
    • Solute
    • Water + sugar = solution
  20. Solutions and cells
    • * cytosol is known as intercellular fluid
    • * Interstital fluid is known as Extracellular fluid
    • * Molecules or ions move from a region of high concentration to low concentration
    • * The difference in concentration is known as concentration gradient
    • [passive transport]
  21. What would happen if you place a cell in a solution?
    • * Hypertonic More solute (H2O moves out; shrink)
    • * Hypotonic Less solute (H2O moves in; Blow up)
    • * Isotonic Equal solute inside and outside (nothing)
  22. It depends on the solution
    • * Hypertonic solution
    • o Higher solute (low water) compaired to the intercellular fluid
    • * Hydrotonic solution
    • o Lower solute (high water) compared to the intercellular fluid
    • * Isotonic solution
    • o Same amount of solute compared to the intercellular fluid
    • * The movement of water from high concentration to low concentration
    • * Solution A has a higher solute concentration which means low water concentration
    • * Solution B has less solute and therefore more water concentration
    • * How would water move?
  23. Facilitated diffusion
    • * Molecules tend to move from high concentration to low concentration
    • * However, molecules can not pass through the membrane
    • * Molecules pass through protein channels embedded within the membrane
  24. Diffusion through a cell membrane
    • * Oxygen molecules move from a high concentration to a low concentration
    • * Carbon dioxide molecules move high to low to low concentration
  25. Endocytosis & Exocytosis
    • * Large molecules that cannot get to the cell by passive or active transport
    • * Endocytosis:
    • o Phagocytosis = cell eating
    • o Pinocytosis = cell drinking
    • * Exocytosis:
    • o Moving large molecules out of the cell
    • * [Bulk transport; bring in large particles]
  26. Active Transport
    • * Movement of molecules from low concentration to high concentration
    • * It required expenditure of energy
    • [through Protein only]
  27. Filtration
    * Filtration forces molecules to move through the membrane
Author
dwatters
ID
73970
Card Set
Chapter Three
Description
Bio 100
Updated