1. plasma membrane
    • surrounds cell
    • made of proteins and lipids
    • composition and function can vary from one region of cell to another
  2. cytoplasm
    • cytosol
    • cytoskeleton
    • organelles
  3. structures in the cytoplasm
    • organelles, cytoskeleton, inclusions
    • all embedden in clear cytosol
  4. organelles
    internal structures of a cell that carry out specialized metabolic traits
  5. membranous organelles
    • those surrounded by one or more layers of membrane
    • nucleus, mitochondria, lysosomes, peroxisomes, ER, golgi complex
  6. organelles not surrounded by membrane
    ribosomes, centrosome, centriole, basal bodies
  7. cytoskeleton
    • keeps everything together
    • collection of protein filaments-microfillaments, intermediate filaments, microtubules
  8. inclusion
    stored cellular components and fat droplets
  9. What is the function of the cytockeleton?
    to determine shape of the cell, lend structural support, organize its contents, direct movement of substances through the cell, and contribute to cell movement as a whole
  10. microfilaments
    • made of actin
    • form a network on cytoplasmic side of plasma membrane celled the terminal web-supports cell
  11. intermediate fibers
    • are thicker and stiffer than microfilaments and resist stresses placed in the cell
    • help junction with other cells
  12. microtubules
    • cylinders that are thick tubes
    • very important in drug target
    • long and hollow and made of globular porteins
  13. Definition of a cytoskeleton functions
    • determines shape of cell
    • lends structural support
    • organizes its contents
    • directs movement of substances through the cell
    • contributes to the movement of cells as a whole
  14. miotic spindle
    array of microtubules and associated molecules that form between the opposite poles of a eukaryotic cell during mitosis and serves to move the duplicated chromosomes apart
  15. microtubules are in a state of
    dynamic instability and constantly assembling and disassembling
  16. Molecular motors
    • kinesins, dyneins, dynamin and myosin
    • molecular molecules move things and require ATP to move
  17. nucleus
    • largest organelle
    • most cells have one
    • consists of nuclear envelope and nucleoplasm
    • keeps DNA
  18. nuclear envelope
    • 2 unit membranes surrounds nucleus
    • perforated by nuclear pores that regulate molecular traffic
    • supported by nuclear lamina
  19. nucleoplasm
    • materials in nucleus
    • chromatin and nucleoli
  20. chromatin
    thread like material composed of DNA and protein
  21. nucleoli
    one or more dark masses where ribosomes are produced
  22. nucleus composition
    made up of chromosomes which are DNA
  23. Endoplasmic reticulum
    • system of interconnected channels called cisternae enclosed by unit membrane
    • rough and smooth
  24. Rough ER
    • composed of parallel flattented sacs covered with ribosomes
    • produces the phospholipids and proteins of the plasma membrane
    • synthesizes proteins
  25. smooth ER
    • lack ribosomes
    • synthesize steroids and other lipids
    • detox alcohol
  26. ribosomes
    small granules of protein and RNA
  27. Where are ribosomes found
    nucleoli, cytosol, outer surfaces of rough ER, nuclear envelope
  28. What do ribosomes do?
    • They read coaded genetic messages from mRNA and assemble amino acids into proteins
    • where proteins are made
  29. Golgi complex
    • a small system of cisternae that synthesizes carbohydrates and put the finishing touches on protein and glycoprotein synthesis
    • gets from rough ER and packages them
  30. lysosomes
    package of enzymes bound by a single unit membrane
  31. what are the functions of lysosomes?
    • intracellular hydrolytic digestion of proteins, nucleic acids, etc
    • autophagy and autolysis
  32. autophagy
    digest and dispose of worn out mitochondrial and other organelles
  33. autolysis
    • cell suicide
    • some cells are mant to do certain jobs and then destroy themselves
  34. peroxixomes
    resemble lysosomes but contain different enzymes and not produced by the golgi complex
  35. what are the functions of peroxisomes
    • they convert things to H2O2
    • detox alcohol and break down fatty acids
  36. inclusions
    • stored cellular products and foreign bodies
    • not needed in cell ofr survival and never enclosed by a membrane
  37. diffusion
    the process by which a gas or a substance in a solution expands because of the motion of its particles to fill all the available volume
  38. what is the flow in diffusion?
    from solute particles from high to areas of low concentration
  39. osmosis
    • the diffusion of solvent molecules into a region in which there is a higher concentration of a solute to whihc the membrane is impermeable
    • a certain pressure involved
  40. osmotic pressure
    • one osmole equals the gram molecular weight of a substance divided by the number of freely moving particles that heach molecule liberates in solution
    • ex- if solution ionizes= number of moles/ions present
    • if does not ionize= 1
  41. tonicity
    • ability of a solution to affect fluid volume and pressure in a cell
    • depends on concentration and permeability of solute
  42. hypotonic solution
    • has a lower concentration of non permeating solutes than ICF
    • cells absorb water and swell and may burst
  43. hypertonic solution
    • has a higher concentration of non permeating solutes and a low water concentration
    • cell loses water and shrivels
  44. isotonic solution
    concentrations in cell and ICF are the same so there is no change in cell volume or shape
  45. cell membrane
    • it is a semipermeable membrane where only certain things can go through
    • it has a hydrophilic heads on the outside and hyrophobic region inside the membrane
  46. transmembrane proteins
    proteins that completely span the bilayer
  47. proteins can be embedded in the inner or outer of the lipid bilayer
  48. peripheral proteins
    loosely bound to the outer or inner surface of the membrane
  49. glycocalyx
    • unique fuzzy coat external to the plasma membrane
    • functions are protection, cell adhesion, immunity, defense, fertilization, embryonic development
  50. microvilli
    • serve to increase surface area of cell
    • serve to help increase absorption and are made of actin
  51. cilia
    • hair like things that are on cell for sensory (ear nose) and can beat in waves and move mucus out
    • move by power strokes
  52. flagella
    • tail of a sperm
    • move around in a whip like structure and are very long
Card Set
lecture 3