Cell Organelles

  1. Nucleus
  1. Control center
  2. Holds information and instructions
  3. Surrounded by a nuclear envelope (double membrane) which contains tiny openings (pores) which allow materials to move out of nucleus
  4. Contains nucleolus which is a dark area that manufactures rRNA to make ribosomes
  5. Holds DNA – genetic info in long thin threads wrapped around histone proteins (chromatin)
  6. Chromatin coils into chromosomes for cell division
  7. Found only in eukaryotic cells
  1. Plasma Membrane
  1. Phospholipid bilayer – fluid mosaic
  2. Outer boundary of cell – all cells have one
  3. Contains proteins

1)Integral – penetrate bilayer

2)Peripheral – attached to surface

3)Channel, carrier, receptor ,recognition, enzymatic, transmembrane

  1. Semi-permeable –controls what goes in and out of cell
  2. Contains cholesterol – prevents freezing
  3. Passive and active transport
  4. Glycoproteins and glycolipids
  1. Ribosomes
  1. Found in prokaryotic and eukaryotic cells
  2. Make proteins (protein synthesis site)
  3. Tiny
  4. 2 subunits (large and small)
  5. Read mRNA
  6. Free (in cytoplasm)
  7. Bound (attached to rough ER
  1. Endoplasmic Reticulum
  2. Membrane structure only in eukaryotic cells
  3. Transports materials
  4. Site of manufacturing materials
  5. Rough (studded w/ ribosomes)
  6. Smooth
  7. Attached to nuclear envelope
  8. Smooth and rough are continuous with each other
  9. Materials travel through and reach the end where they are packaged in a ER membrane bubble (vesicle)
  10. Golgi Complex
  11. only in eukaryotic cells
  12. flattened sacs
  13. vesicles from ER join with it and empty contents inside
  14. materials are modified and packages for secretion
  15. materials leave opposite side via vesicles that can fuse with plasma membrane and release contents out of cell, or can become vacuoles or lysosomes
  16. Vacuole
  17. Only in eukaryotic cells
  18. Storage sac
  19. Large, central vacuole in plants holds water and puts pressure on cell wall to give plants support
  20. Contractile vacuole in single celled organisms pumps water out of cell so it won’t explode
  21. Lysosome
  22. Only in eukaryotic cells
  23. Membrane pocket filled with hydrolytic enzymes
  24. Forms from Golgi
  25. Digests food,waste and old organelles
  26. Mostly in animal cells
  27. Mitochondria
  28. Only in eukaryotic cells
  29. Double membrane
  30. Inner membrane is folded (cristae)
  31. Liquid inside = matrix
  32. Cellular respiration
  33. Enzymes in cristae
  34. Produce ATP from sugar
  35. Powerhouse of cell
  36. Contains own DNA and ribosomes
  37. Sugar + oxygen = carbon dioxide + water
  38. Chloroplasts
  39. Only in eukaryotic plant and algae cells
  40. Double membrane
  41. Contains own DNA & ribosomes
  42. Inner membrane in disc-like structures = thylakoids
  43. Thylakoids are stacked = grana
  44. Liquid inside = stroma
  45. Contain green pigment (chlorophyll)
  46. Photosynthesis
  47. Carbon dioxide + water + light = sugar + oxygen
  48. Plastids
  49. Only in plant cells
  50. various functions
  51. chloroplasts (see above)
  52. leucoplasts (store starch)
  53. chromoplasts (contain pigments other than green)
  54. Peroxisomes
  55. Contain enzymes that transfer hydrogen to oxygen making hydrogen peroxide which is then broken down to water
  56. Cytoskeleton
  57. Made of proteins

1)Microfilaments (made of actin; smallest)

2)Intermediate filaments

3)Microtubules (made of tubulin; hollow tubes; largest)

  1. Support, shape, motility, anchor spot for organelles, track for organelle movement
  1. Centrioles
  2. Microtubule-based structures
  3. Found only in animal cells
  4. Found in pairs
  5. Located in centrosome area near nucleus
  6. Helps organize cytoskeleton during cell division
  7. Cilia & Flagella
  8. Microtubule structures attached to outside of cell
  9. Provide movement for cell
  10. Cilia = short, humdreds or more on cell surface
  11. Flagella = long, only one or two
  12. Cell Wall
  13. Only in plant cells, fungal cells, some prokaryotes and some protists
  14. Made of cellulose in plant cells
  15. Made of chitin in fungal cells
  16. Primary cell wall
  17. Secondary cell wall (between primary and plasma membrane)
  18. Middle lamella (made of pectin) – between cells
  19. Rigid support for cell
  20. Works with central vacuole in plant cells to hold plant up