| Question |
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| Answer |
|
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| cell membranes are composed primarily of ? |
proteins and lipids |
| approximate percentage that is proteins and lipids |
55%protein , 25% phospholipid, 13% cholesterol , 4 % other lipids, and 3% carbohydrates |
| 2 types of lipids |
phosopholipids and cholesterol |
| what is meant by lipid bilayer? |
fat soluble molecules can pass through it |
| as a general rule is the lipid barrier water soluble? |
yes |
| fluid mossiac model |
bi layer is fluid not rigid molecules may move latertally |
| most proteins in the cell membrane are? |
glycoproteins |
| integral proteins are? |
passes all the way through the cm.
channel , enzymes, and carrier proteins
|
| peripheral prteins are? |
attached only to the surface of the cell membrane.
usually an enzyme
|
| endocytosis is? |
the movement of molecules into a cell that are too large to enter.
pinocytosis,phagocytosis,and receptor-mediated |
| exocytosis is? |
the reverse of endocytosis |
| what 2 general processes do small molecules use to pass through a cell membrane? |
diffusion and active transport |
| diffusion is? |
the net moveemoent of molecules higher to lower.
3 factors effecting this are: magnitude of cencentration gradient,permability of the cmto the diffusing, and surface area. |
| is a carrier protein required for simple diffusion? |
no |
| 2 types of simple diffusion |
direct movement through the cm and movement through watery channels |
| do all types of channels use simple diffusion? |
yes |
| osmosis is |
the flow of water molecule through a selectively permiable membrane from ares of greater to lesser concentration. |
| osmosis conditions |
2 compartments of water, seperated by selectivly permiable membrane, concentration difference |
| will non permiable particle pass through the membrane? |
no |
| osmotic preassure |
the amount of preassure that must be applies to prevent the flow of water during osmosis |
| what determines the magnitude of osmotic preassure? |
concentration of solute to the # of solvent the greater solute the greater OP |
| 3 ways to increase solute concentration? |
increase # of particles, decrease # of solvent |
| 2 formulas for concentration? |
molarity=moles/liters
osmolarity=osmoles/liters |
| how many molecules of a given compound are there in one mole? |
6.02*10 ^ 23 |
| how many in one osmole? |
6.02 * 10^23 |
| formula for molarity to osmolarity? |
molarity X number of particles/molecule=osm |
| osmolarity |
describes the # of particles per liter of solution |
| isomotic |
the osmolarity of 2 solutions are the same |
| hyperosmotic |
the osm. of the first is greater then the second |
| hyposmotic |
the osm of the first is less then the second |
| tonicity |
term that describes what happens to the cell volume when the cell is placed in solution |
| tonicity depends on what? |
comparisson of osm of the solution to cell and nature of the particles |
| crenation |
to shrink |
| hemolysis |
to rupture |
| what requires the push for facillitated diffusion? |
concentration gradient and carrier protein is needed |
| active transport? |
movement of ions or molecules from an area of lesser to greater |
| cotransporter (symport) |
same direction |
| counter transporter (antiport) |
different directions |
| what are the intrinsic controol mechanisms of cellular metabolism? |
genetic regulation, enzyme activity |
| exocrine |
enters a tube that lead to a free surface |
| endocrine |
goes directly into the blood |
| hormone |
chemical substance realeased into blood |
| classification of hormones by structure |
dirivapolypeptides and glycoproteins tives of amino acid tyrosine, steroids |
| why do some cells respond to hormones? |
b/c of receptors |
| alternate names for ant and post pituitary |
adenohypophysis and neurohypophysis |
| what controls secretion from endocrine gland? |
intrinsic control mechanisms |
| what is meant by down and up regulation? |
decrease in # of receptors and increase |
| another name for growth hormone? |
somatotropin |
| catabolic effect of GH? |
direct effect |
| anabolic effect of GH? |
indirect effect |
| somatomedians |
insulin like growth factors |
| gigantism |
excessive GH in children |
| acromegaly |
excessive GH in adults |
| what hormones are produced by thyroid? |
t3(active) t4 thyroid hormones TSH |
| t3 causes |
stimulates protein synthesis needed for growth premotes developement helps set the basale metabolic rate |
| two regions of adrenal gland |
medulla and cortex |
| adrenal gland |
releases epinephrine |
| function of aldosterone |
helps regulate sodium and potassium |
| whats releases glucagon and the effects |
secreated in response to blood glucose levels, glycogenolysis,glucogenesis, and lipolysis |
| what stimulates the release of insulin |
increase blood glucose levels, |
| effects of insulin |
needed for movement of glucose liver adipose tissue inhibits secretion of glucogen |
| sensitivity to insulin receptors |
increased by excersise decreased by obesity and pregnancy |
| symptoms of diabetes |
cronic high blood glucose |
| different form of diabetes |
insulin dependant and non insulin dependant |
BIOL3326 Forms
