1st Evals 2017 - Cell Physiology & Electrophysiology Flashcards
objective of homeostasis is to maintain the immediate environment of the cell which is the
interstitial fluid
contration of protein is higher in ECF or ICF?
ICF
total volume of ECF & ICF
ICF = 40% of body weight ECF = 20% of BW
GAIN formula
GAIN=Correction/Error
conditions that are constantly regulated by homeostatic control include:
a. oxygen concentration
b. blood pH
c. body temp
d. all of the above
d. all of the above
the following organs function towards maintenance of homeostatic conditions in the “internal environment” of the cell, EXCEPT:
a. digestive tract
b. kidneys
c. lungs
d. ovary and testis
sabi sa pastE B, feeling ko D.
ewan. not sure.
“internal environment of the fell that is the object of homeostasis is
extracellular fluid (ECF).. actually yung insterstitial fluid, un na din yun kasi nasa ECF yun.
the measure of the efficiency of the homeostatic mechanism
gain
In hemorrhagic shock, death is likely to ensue following decreased blood flow to the
heart
in the redundancy of control of blood glucose levels, all of the following can increase blood glucose, EXCEPT:
a. insulin
b. glucagon
c. glucocorticoid
d. epinephrine
A. insulin
MUST BE PRESENT IN OSMOSIS, but is not necessarily present in simple diffusion
semi-permeable membrane
occurs in osmosis:
WATER moves from area of (high or low?) SOLUTE concentration to area of (high or low?) solute concentration
low to high
in tonicity, WATER moves from area of (higher/lower?) SOLVENT concentration to area of (higher or lower?) solvent concentration.
higher to lower
from hypotonic solution to hypertonic solution
reflection coefficient of a solute to which the cell membrane is impermeable
1
di ko alam kung bakit
In Gibbs-Donnan Equilibrium, the ff components are found in greater amount in ICF than in the ECF, EXCEPT:
a. diffusible cations
b. diffusible anions
c. total diffusible ions
d. total volume
b. diffusible anions.
kasi yung Protein na negatively charged ay hindi diffusable.
which of the ff occurs in protein mediated transport in cell membrane?
a. stereospecificity
b. competition
c. saturation
d. all of the above
d. all of the above
facilitated transport - uphill or downhill?
downhill
active transport - uphill or downhill?
uphill
hydrolyze ATP
lahat ng active transport
mediated by transport proteins
both facilitated and active transport
direct hydrolysis of ATP occurs in the transport by:
primary active transport
indirect hydrolysis of ATP occurs in the transport by:
secondary active tranport (both co-transport and counter-transport)
transport of solutes by the Na+-K+ ATPase pump is by:
primary active transport
for most secondary active transporters, the hydrolysis of ATP is from the activity of the
Na+-K+ ATPase
what structure in effector cells allows the recognition of appropriate chemical signals from other cells?
receptors
second messengers
- intracellular MEDIATOR that triggers the effect of the hormone/transmitter
- amplifies the response
second messengers…
a. interact with ligands outside the cells
b. bind to ligands in the cell membrane
c. are hormones secreted by cells in response to another hormone
d. mediate the intracellular response to other chemical messengers
D. MEDIATE the intracellular response to other chemical messengers.
up-regulation occurs…
- when the concentration of the signal molecule is chronically low
- when there is an increase in the number of receptors
- results in an increase in sensitivity of the effector cell
down-regulation occurs
- when the concentration of the signal molecule is chronically high
- when there is an decrease in the number of receptors
- results in decreased sensitivity of the effector cell to the signal molecule
receptors for lipid-soluble ligands are found in the
nucleus and
cytoplasm
receptors for water-soluble ligands are found in the
cell membrane
GPCR signalling (steps)
- activation by receptor-ligand binding
- receptor interacts with G-protein: GDP converted to GTP
- G-Protein dissociates from receptor
- alpha-GTP and beta-gamma subunits dissociate
- both alpha-GTP and beta-gamma subunits interact with their effectors
- hydrolysis of GTP to GDP inactivates alpha, reassembly of trimer.
transport for lipid-soluble substances
simple diffusion
transport is driven by concentration gradient for Na+ inside the cell
secondary active transport
membrane protein requires ATP in conformational change to transport solutes
primary active transport.
direct na kailangan ng ATP; yun kasing secondary, indirect.
transport mechanism can be saturated
facilitated diffusion at active transport
di ko alam kung bakit
which of the following membrane transport proteins is “non-gated”?
a. membrane pore
b. channel proteins
c. carrier proteins
d. all of the above
A. membrane pore
transfer of glucose with Na+ across intestinal epithelium
secondary active transport (co-transport)
- –yung Na+-iodide symport, co-transport din yun.
- –yung Na+-Ca++, Na+-H+, at H+-K+, ay puro counter-transport
examples of counter-transport
Na+-Ca++
Na+-H+
H+-K+
the transport of glucose by glucose transporter proteins that is stimulated by insulin is by:
facilitated diffusion
the tonicity of a solution is determined b its concentration relative to:
water
cell in hypotonic soln will swell or shrink?
swell
cell in hypertonic soln will swell or shrink?
shrink
the release of cell secretion into the ECF/ the release of lytic contents of lysosomes by macrophages in the destruction of viral infected cells
exocytosis
kabaliktaran ng exocytosis kasi into the cell naman
endocytosis
uptake of soluble material (endocytosis)
pinocytosis
uptake of particulate material (endocytosis)
phagocytosis
cellular communication that elicits the most diffused and generalized response
endocrine
amplify the effects of the transmitter substance
second messenger
second messengers (DOES/DOES NOT) interact with ligand/transmitter substance
DOES NOT
the nicotinic acetylcholine-NA+ channel is a/an:
ion-linked channel receptor
G-protein coupled receptors are activated by:
receptor-ligand interaction
causes mobilization of intracellular Ca++ is:
inositol-triphosphate
both Na+ and K+ are moved against their concentration or electrical gradients across the membrane because of:
Na+-K+-ATPase system
