INTRO Flashcards
Frederick banting
1923- insulin
charles huggins
1966- how hormones control the spread of some cancers
david hubel
1981- information processing in the visual system
jack szostak
2009- how chromosomes are protected by telomeres
ralph steinman
2011- the dendritic cells and its role in adaptive immunity
physiology
study of normal functioning of a living organism and its compoenent parts including chemical and physical processes
what makes up 99%
Oxygen, carbon, hydrogen, nitrogen
what makes up 1%
calcium, phosphorus, potassium
four primary types of tissues
nervous tissue- electrical impulse transmission
muscle tissue- force generation
epithelial tissue-secretory function
connective tissue-support and anchoring function
organ level
two or more types of primary tissue
organ example
stomach: inside wall is lined with epethelial tissue
wall of stomach contains smooth muscle
nervous tissue controls contration and gland secretion
connective tissue binds it all together
do body systems act in isolation
no
central concept of physiology
homeostasis
intrinsic control system
local control of muscle
extrinsic control system
nervous and endocrine control of various organs
examples of positive feedback
childirth
wound clotting
ECF
Extracellular fluid
contains plasma and interstitial fluid
functions of cell membrane
physical barrier
gateway for exchange
communication
cell structure (junctions stabilize tissue structure)
examples of membrane proteins
ion channels
carrier molecules
membrane bound enzymes
receptors
cell adhesion molecules
can aqueous molecules go through the membrane
no unless they have some sort of transportaion
assisted transport
carrier mediated
-passive or active
vesicular transport
two properties influence if substance can permeate without assitance
relative solubility
size of particle
what are the two forces that drive molecules to permeate the plasma membrane on their own
chemical and electrical
(electrochemical)
no net diffuction
steady state
diffusion across a lipid bilayer
simple diffusion
how is diffusion across a lipid bilayer controlled
the surface area of the membrane and the thickness of the membrane, concentration gradient, molecular wieght, – FICKS LAW OF DIFFUSION
tonicity
the effect a solution has on cell volume (non penetration solutes)
hypotonic
more solute inside and SWELL
hypertonic
more solute outside and SHRINK
facilitated diffusion
passitve transport (down concentration gradient)
example of facilitated diffusion
transport of glucose into a cell
difference bw carrier mediated transprt and simple diffusion
carrier mediated is directly proportional to concentration gradient until the carrier is saturated
NA K pump how many in and out
3 Na out
2 K in
phagocytosis
actin mediated process by which a cell engulfs a particle into a large membrane bound vesicle called a phagosome
what produces and packages materials for secrection
ER and golgi complex
what requires exocytosis
secretion of horomes or enzymes, addition of compoenents to membrane, membrane recycling
what regulates the release of secretory vesicles
intracellular Ca2+
what is membrane potential influenced by
permeability of a few important ions
where does seperation of charge take place
across the membrane
what determines membrane potential
- concentration of ions inside and outside
- permability
- activity of electrogenc pumps
potential
separation of charge
where are the negative charged proteins that are impermeable in the cell membrane
inside the cell
what is membrane potential measured in
milivolts
resting membrane potential
-70, minus means cells is negative on inside
permability of Na
moderate
permeability of k
high
permeabiity of A-
no permeability
eqm potential for k
-90
eqm potential for Na
+60
equilibrium potential
in a cell that is permeable to just one ion, the membrane potential that exactly opposes the concentration gradient
why is the membrane potential closer to that of k and not Na
becasue at rest the membrane is 50-75x more permeable to k so it infleunces the resting membrane portential to a greater extent
concentration of Cl
higher in ECF
permeability of Cl
high
eqm potentioa of Cl
-70
depolarization
net inward flow of +ve ions
hyperpolarization
net outward flow of +ve ions
repolarization
returning to resting potential after being deporalized
types of gated channels
- voltage
- chemically
- mechanically
- thermally
2 types of electric signals
- graded
- action
graded potentials
local changed in membrane potential in small specialized region of excitable cell membranes produced by triggering events. magnitude and duration is related to magnitude and duration of triggering event
what kind of gated channels for graded potentials
chemically or mechanically
how can depolarixation spread from a trigger zone
by local current
can current loss occur across the membrane
ye
signalling distance of graded potential
limited due to currrent loss but graded potentials can sum to initiate action potentials
equation used to calculate the resting membrane potential at 37
GHK equation
