Cellular level of organization

  1. What is a cell?
    Basic structural living and functional unit of the body
  2. What is cytology?
    Study of the cell
  3. What are parts of the cell?
    • plasma membrane/cell membrane
    • cytoplasm/cytosol
    • organelles
    • inclusions
  4. Functions and characteristics of the plasma membrane
    • Separates one cell from another
    • Separates a cell from external environment
    • Made up of phospholipid and protein (lipo-protein)
    • It is semipermeable - only allows certain substances to enter which will depend on the size of the molecule, the lipid solubility (can be dissolved), electrical charges of the molecule (positive or negative), and presence of the carrier
  5. What is passive movement/process?
    • Little to no movement is required by the cell.
    • Movement is from high concentration to low concentration
  6. What are the 5 types of passive movement?
    • Diffusion
    • Facilitated diffusion
    • Osmosis
    • Filtration
    • Dialysis
  7. Diffusion
    • Spreading
    • Net movement of molecules or ions from one area of high concentration to low concentration
  8. Facilitated diffusion
    Requires a carrier

    i.e. - glucose will combine with a carrier, like insulin, to become soluble in the lipid portion of the membrane
  9. Osmosis
    Movement of water molecules from an area of high concentration to low concentration.

    i.e - osmotic pressure - force under which a solvent (liquid) moves from a solution of lower solute (solid) concentration to a higher solute concentration
  10. Filtration
    Movement of water and dissolved substances across the membrane under pressure
  11. Dialysis
    Separation of small molecules from large molecules by diffusion
  12. What is active movement/process?
    • Requires energy produced by the cells
    • Movement of ions across the membrane and maybe from lower concentration to high concentration
    • May require a carrier
  13. What are the 2 types of active movement?
    Phagocytosis - phago = to eat; cyt = cell; osis = condition

    Pinocytosis - pino = to drink; cyt = cell; osis = condition
  14. Phagocytosis
    The ingesting or engulfing of solid particles

    • i.e. white blood cells (pseudopods)
    • pseudo = false; pods = feet
  15. Pinocytosis
    The ingesting or engulfing of liquid particles (common around the lungs)
  16. Tonicity - tonic = tension
    The effects of various concentrations of water on the shape of the cell
  17. What are the 3 types of tonicity?
    • Isotonic - iso = equal/the same
    • Hypotonic - hypo = below/less than
    • Hypertonic - hyper = greater than
  18. Isotonic
    Having the same concentration of solvent and solute on each side (Intracellular fluid [ICF] and External cellular fluid [ECF]) of the plasma membrane

    No net movement

    • i.e. 60% solvent/40% solute on the inside
    •       60% solvent/40% solute on the outside
  19. Hypotonic
    Having a lower solute concentration or a high solvent concentration on the outside so water will move from the outside of the cell to the inside

    i.e. red blood cell will swill and burst called hemolysis (hemo = blood; lysis = to loosen/break)

    (Outside) 70% solvent - osmosis occurs - (Inside) 60% solute

    (Inside) 40% solvent - diffusion occurs -  (Outside) 30% solute

  20. Hypertonic
    Having a high solute concentration therefore a less solvent concentration, so water will move from the inside the cell to the outside causing shrinkage (crenation)

    (Inside) 40% solute - diffusion occurs - (Outside) 60% solute

    (Outside) 40% solvent - osmosis occurs - (Inside) 60% solute

  21. Modified plasma membrane
    • Microvilli - micro = small; villi = tufts of hair
    • Rods and cones
    • Mylenin sheath
    • Stereocilia
  22. Microvilli
    • Located in the small intestine
    • Microscopic fingerlike projections that increase the surface area for absorption
  23. Rods and cones
    • Located in the eyes
    • Light sensitive pigment

    • Rods allow us to see dim light
    • Cones produces color vision when stimulated by light
  24. Mylenin Sheath
    • Located on nerve cells
    • Protects, conduction of nerve impulses and provides nutrients
    • Nerves that contain mylenin will conduct impulses the fastest

    i.e. touching fire and quickly pulling your hand away
  25. Stereocilia
    • Long, slender branching cells that line the epididymis (in male reproductive system)
    • Facilities the movement of the sperm cells
  26. Cytoplasm - plasm = formed/molded
    • * Living matter that is located in the cell membrane
    • * External to the nuclear membrane
    • * Contains organelles and inclusions
  27. Cytosol
    Contains waters, dissolved solutions and suspended particles
  28. Physical aspects of the cytoplasm
    • Thick, semitransparent, elastic fluid containing suspended particles
    • Also called colloidal suspension (exist in a sol-gel condition - not a solid or liquid..i.e. like jello substance; whit of the egg)
  29. Chemical aspect of the cytoplasm
    • Contains 75-90% water
    • Contains proteins, carbohydrates, lipids and inorganic substances
  30. Functions of the cytoplasm
    • Area where chemical reactions take place
    • Area where raw materials are converted to energy (i.e. glucose)
    • Area where new substances are made (i.e. protein)
    • Area where chemical substances are packaged to transport somewhere else
    • Facilitates the excretion of water products
  31. Two components of the cytoplasm
    • Organelles
    • Inclusions
  32. What are organelles?
    Structures which are specialized portions of the cell that functions in growth, repair, maintenance and control
  33. Components of the cell membrane
    • Nucleus
    • Endoplasmic reticulum
    • Ribosomes
    • Golgi apparatus
    • Mitochondria
    • Lysosomes
    • Centrioles
    • Centrosome
    • Flagella
    • Cilia
  34. Nucleus of the cell membrane
    • Largest structure in the cell
    • Contains genes which control cellular structures and activities
    • Cells WITHOUT a nucleus will NOT divide or reproduce (i.e. red blood cells)
    • Cells that HAVE a nucleus also will NOT divide or reproduce
    •     i.e. white blood cells
    •            contains nuclear membrane, nucleoli and instructions for protein synthesis
    •            contains the chromosome DNA
    •            produced every 7-10 days in the bone marrow and lymph nodes
  35. Endoplasmic reticulum in the cell membrane and two types
    • Network of parallel membrane continuous with the plasma and nuclear membranes
    •    a) rough endoplasmic reticulum (rough ER) - contains ribosomes (where protein synthesis are made)
    •    b) smooth endoplasmic reticulum (smooth ER) -  where lipid metabolism takes place
Card Set
Cellular level of organization
Cellular level