Cells Flashcards
What is part of the dorsal body cavity
nervous system
Cranial + vertebral cavity
What is part of the ventral body cavity
internal organs
Abdominal, thoracic, pelvic cavity
What does parietal serosa cover
lines cavity walls (outer)
What does visceral serosa cover
covers organs (inner)
What cavities are not exposed to environment
Synovial cavities
Which phospholipids are on the INNER plasma membrane
PI, PE, PS
Which phospholipid is on the OUTER plasma membrane
PC
where can glycolipids be found
only on outer memrbane
Which phospholipids do flippases concentrate
inner
PE, PS
which phospholipids do scramblases concentrate
outer
PC & sphingolipid
What are the 6 functions of membrane proteins
transport
enzymatic activity
Receptors for signal transduction
Intracellular adhesion
Cell-cell adhesion
Attachment to cytoskeleton and EC matrix
What do ANCHORING junctions (desmosomes) do? what provides strength between the cells?
What helps the junctions inside the cell?
- mediate cell-cell and cell-matrix adhesions
- linked to cytoskeleton to transmit and distribute stress (skin & heart muscle)
- cadherins
- tonofilaments, adhesion plaque
- intermediate filaments
What do occluding junctions (tight) do? What helps the tight junctions stay in place?
- impermeable junction to form seals between epithelial cells (eg. intestinal wall for bacteria)
- Actin filaments
What do gap junctions do? is it hydrophobic/hydrophillic
allow diffusion of small molecules (ATP)
and for cell-cell communication
- hydrophilic channel
What is signal-relaying junction
transmit signals ex. synapses
What is passive transport? which type of diffusions are associated
Transport from high to low conc. with no energy
-simple diffusion
- facilitated diffusion
- carrier-mediated
- Channel-mediated
- Osmosis
What types of molecules diffuse in simple diffusion
non-polar and lipid- soluble subs. (hydrophobic)
- Ex. O2, CO2, fat soluble vitamens
what happens in facilitated diffusion? what are the 2 types and differences
Carrier-mediated: glucose, AA binds to carrier proteins (hydrophilic) for a conformational change; lipid insoluble
Channel-mediated: only lets ions through
How does osmosis work
WATER moves from high solute conc. to low solute conc.
- semipermeable; can go through aquaporin (channel protein) or through lipid bilayer
What is an isotonic solution mean and what effect on the cell
Solution with the same conc. as cytosol
(no effect)
What is an hypertonic solution mean and what effect on the cell
solutions with greater conc. outside the cell
- water leaves the cell and cell shrinks
What is an hypotonic solution mean and what effect on the cell
solutions with less conc. outside cell
- water comes in the cell and cell swells
What is a symport system; antiport?
symport: 2 substances move across the membrane in SAME direction
Antiport: move in opposite direction
Differences between primary active transport and secondary active
Primary: direct transport by hydrolysis of ATP causing conformational change
- 3 NA+ out, 2K+ in
Secondary: indirect; uses gradient from primary to transport glucose or AA
