Question 1
Answer
-
are chemical regulators that are conveyed from one organ to another via the blood stream
-
may be secreted by endocrine glands
-
may be secreted by nerve cells
-
act only on target cells
-
all of the above
Question 2
Question
For an action potential to occur
Answer
-
the stimulus must reach or exceed threshold
-
K+ influx must exceed Na+ efflux
-
The cell membrane must be out of the relative refractory period
-
The cell membrane must be in absolutely refractory period
-
Cl- influx must exceed K+ efflux
Question 3
Question
During the rising phase of the action potential
Answer
-
voltage-gated Na+ channels open
-
voltage-gated K+ channels open
-
voltage-gated Na+ channels close
-
voltage-gated K+ channels close
-
voltage-gated Cl- channels apex
Question 4
Question
The concept of homeostasis
Answer
-
refers to the unwavering control of a physiological set point
-
refers to maintaining physiological functions in a stable condition
-
refers only to the regulation of body temperature
-
refers to maintaining a stable external environment
-
refers to the 'all-or-one' law
Question 5
Question
The plasma membrane
Answer
-
is permeable to lipophilic molecules
-
may contain proteins, which confer iron permeability
-
may burst in hypotonic extracellular solutions
-
can generate action potentials in excitable cells
-
all of the above
Question 6
Question
Overcooling the nerve will cause
Answer
-
decrease of the threshold
-
increase of the liability
-
increase of the excitability
-
increase of the threshold
-
increased release of neurotransmitters
Question 7
Question
The properties of local response:
Answer
-
'all-or-none’ law
-
transmission with energy consumption
-
without energy consumption
-
summation
-
excitability is decreased
Question 8
Question
A “less negative" membrane potential means:
Question 9
Question
The membrane of a typical resting neuron is largely impermeable to
Answer
-
Na+
-
K+
-
Cl-
-
Ca2+
-
none of the above
Question 10
Question
The ion with the lowest intracellular concentration is:
Question 11
Question
The most common intracellular cation is:
Answer
-
calcium
-
sodium
-
potassium
-
phosphorus
-
magnesium
Question 12
Question
What is the normal pH value of body fluid?
Answer
-
7.15-7.25
-
7.35-7.45
-
7.55-7.65
-
7.00-7.35
-
6.5-7.5
Question 13
Question
Which of the following requires energy?
Answer
-
Diffusion
-
Osmosis
-
Active transport
-
Facilitated diffusion
-
Filtration
Question 14
Question
Which of the following is not found in the cell membrane?
Answer
-
Cholestrol
-
Phospholipids
-
Proteins
-
Galactose
-
Nucleic acids
Question 15
Question
The local response is:
Answer
-
A potential that is generated as a result of the action of a subthreshold stimulus and propagated along the nerve cell membrane
-
A potential that is generated as a result of the action of a superthreshold stimulus and propagated along the nerve cell membrane
-
A potential that is generated as a result of the action of a subthreshold stimulus and could be registered only at the site of irritation
-
A potential that is generated on the postsynaptic membrane as a result of the action of a mediator
-
A potential that is generated as a result of the action of a superthreshold stimulus and could be registered only at the site of irritation
Question 16
Question
The oculocardiac reflex is an example of:
Question 17
Question
Norepinephrine is a neurotransmitter with the highest affinity to:
Question 18
Question
The parasympathetic post-ganglionic neurons of the ANS secrete
Answer
-
Nor-epinephrine (98%) and epinephrine (2%)
-
Acetylcholine
-
L-DOPA
-
Nor-epinephrine (2%) and epinephrine (98%)
-
Epinephrine (80%) and nor-epinephrine (20%)
Question 19
Question
The critical (firing) level of depolarization is
Answer
-
a level of AP at which depolarization goes into repolarisation
-
a level of AP at which repolarization goes into depolarization
-
a degree of depolarization of the postsynaptic membrane at which further action of the neurotransmitter is abolished
-
a degree of depolarization of the nerve cell membrane at which its sources of energy are completely exhausted
-
a degree of depolarization of the excitable membrane at which its intensity does not depend on irritant action
Question 20
Question
A structure that permits a neuron to pass an electrical or chemical signal to another cell (neural or otherwise) with excitatory or inhibitory effects is called:
Question 21
Question
H1 receptors are situated an the smooth muscle cell membrane of the:
Answer
-
gastrointestinal tract
-
urinary tract
-
bronchi
-
uterus
-
blood vessels
Question 22
Question
The adrenergic effect an the cardiac conduction system and working myocardium is exercised by affecting:
Answer
-
M-choline receptors
-
α1 receptors
-
α2 receptors
-
β1 receptors
-
β2 receptors
Question 23
Question
The parasympathetic spinal centers, regulating the reservoir functions, are situated in the following
Answer
-
C8-Th1
-
Th1-Th8
-
Th10-L2
-
S2-S4
-
L2-L4
Question 24
Question
Facilitated diffusion is a mechanism:
Answer
-
Connected with loss of energy
-
For transporting substances against their concentration gradient
-
Connected with membrane polarity
-
That works with the help of a carrier in the membrane
-
For transporting lipid soluble substances through the membrane
Question 25
Question
A distinguishing feature of the membrane potential at rest is:
Answer
-
high permeability for K+ ions
-
low permeability for Cl- ions
-
low permeability for Na+ and high for K+ ions
-
the small difference between the equilibrium potentials for Na+ and K+ ions
-
low permeability for Na+
Question 26
Question
Acetylcholine is a neurotransmitter which has:
Answer
-
always an excitatory effect on the postsynaptic membrane
-
always an inhibitory effect on the postsynaptic membrane
-
excitatory or inhibitory effect on the postsynaptic membrane depending on the type of receptors
-
excitatory or inhibitory effect depending on the amount released
-
no effect on the postsynaptic membrane
Question 27
Question
The common expression of excitation is:
Question 28
Question
Curare is a substance that blocks
Question 29
Question
An example of a ligand dependent membrane is
Question 30
Question
Throughout the relative refractory period:
Answer
-
the excitability becomes equal to zero
-
the excitability is equal to that at rest
-
the excitability is higher than that at rest
-
accommodation occurs
-
the excitability is lower than that at rest
Question 31
Question
Na/K pump is called electrogenic, because:
Answer
-
exports equal amount of Na+ and K+
-
imports equal amount of Na+ and K+
-
exchanges equal amount of Na+ and K+
-
the exchanged amount of Na+, and K+ is not equal
-
none of the above
Question 32
Question
The conditioned reflexes are:
Question 33
Question
Which of the statements is not true:
Answer
-
at the chemical synapse transmission of excitation is one way
-
at most of the electrical synapses transmission is two-way
-
the velocity of transmission of excitation is higher at the chemical synapses than at the electrical ones
-
the velocity of transmission of excitation is greater at the electrical synapses than at the chemical ones
-
when there is continuous excitation at a synapse, fatigue occurs
Question 34
Question
Which is the basic inhibitory neurotransmitter in CNS:
Answer
-
Glutamate
-
Substance P
-
Neuropeptide 4
-
GABA
-
Nitric Oxide
Question 35
Question
The basic factor for the ion asymmetry on both sides of the excitable membrane is
Answer
-
Ca++ pump and the low permeability for Na+
-
Na+ pump and the low permeability for Na+
-
Na+/K+ pump and the low permeability for Na+
-
K+ pump and the high permeability for Na+
-
Iodine pump
Question 36
Question
The velocity of AP propagation along the axon membrane depends on:
Answer
-
the strength of irritation
-
the duration of irritation
-
the cross sectional area of the axon
-
the direction of its propagation
-
the threshold
Question 37
Question
The sympathetic postganglionic neurons secrete:
Answer
-
norepinephrine (98%) and epinephrine (2%)
-
acetylcholine
-
L-DOPA
-
norepinephrine (2%) and epinephrine (98%)
-
epinephrine (20%) and norepinephrine (80%)
Question 38
Question
The result of activated α1-adrenergic receptors is:
Answer
-
relaxation of the gastrointestinal tract smooth muscles and contraction of the sphincters
-
constriction of the vessels smooth muscle
-
increased heart rate
-
dilation of the vessels smooth muscle and relaxation of the uterus
-
none of the above
Question 39
Question
The result of activated α2-adrenergic receptors is:
Answer
-
relaxation of the gastrointestinal tract smooth muscles and contraction of the sphincters
-
constriction of the vessels smooth muscle
-
increased heart rate
-
dilation of the vessels smooth muscle and relaxation of the uterus
-
none of the above
Question 40
Question
Protein synthesis occurs at the
Answer
-
mitochondria
-
lysosomes
-
within the nucleus
-
ribosomes
-
vacuoles
Question 41
Question
During repolarization of the cell membrane:
Answer
-
Na+ move inside of the cell
-
Na+ move outside of the cell
-
K+ move inside of the cell
-
K+ move outside of the cell
-
Cl- move outside of the cell
Question 42
Question
In a cell, movement of molecules from an area of low concentration to an area of high concentration:
Answer
-
uses facilitated diffusion
-
requires cellular energy
-
is passive transport
-
requires both cellular energy and facilitated diffusion
-
uses its concentration gradient to move
Question 43
Question
Movement of solvent and dissolved substances across a cell membrane by hydrostatic pressure is:
Answer
-
filtration
-
facilitated diffusion
-
osmosis
-
simple diffusion
-
active transport
Question 44
Question
The substance acetylcholine (ACh) is released from synaptic vesicles by the process of:
Answer
-
phagocytosis
-
simple diffusion
-
passive transport
-
exocytosis
-
endocytosis
Question 45
Answer
-
are formed entirely by protein molecules
-
are impermeable to fat soluble substances
-
in some tissues permit transport of glucose at a greater rate in the presence of insulin
-
are not changed throughout life
-
are permeable to water soluble substances
Question 46
Question
Proteins that are secreted by cells are generally:
Answer
-
not synthesized on ribosomes that are bound to endoplasmic reticulum
-
synthesized in the mitochondria
-
packed in the Golgi apparatus
-
across the cell membrane by endocytosis
-
synthesized in the lysosomes
Question 47
Question
The unique feature in mitochondria is:
Answer
-
myosin
-
actin
-
DNA
-
prothrombin
-
haemoglobin
Question 48
Question
The resting membrane potential of a cell:
Answer
-
is dependent on the permeability of the cell membrane to K+ being greater to Na+
-
falls to zero if Na+/K+ ATPase in the membrane is inhibited
-
is equal to the equilibrium potential for K+
-
is equal to the equilibrium potential of Na+
-
is equal to the equilibrium potential of Cl-
Question 49
Question
Many substances are removed from the cell to the outside by:
Answer
-
pinocytosis
-
chemotaxis
-
phagocytosis
-
exocytosis
-
endocytosis
Question 50
Question
An example of co-transport is:
Answer
-
Na+-K+ pump
-
Ca++ pump
-
Na+-H+ pump
-
Na+ glucose transport
-
Na/Ca pump
Question 51
Answer
-
are the Chief site for lipid synthesis
-
are the chief site for protein synthesis
-
are the chief sites for generation of ATP
-
are more numerous in white than in brown fat cells
-
are absent near the membranes of actively secreting cells
Question 52
Question
The endoplasmic reticulum:
Answer
-
is a complex system of intracellular tubules
-
has a membrane structure similar to the cell membrane
-
is associated with ribonucleoprotein
-
is well developed in secretory cells
-
all of the above
Question 53
Question
The mammalian cell membrane:
Answer
-
is seen as an optically dense line using light microscopy
-
consists mainly of protein
-
is more permeable to fat- than to water-soluble particles
-
contains enzymes DNA
-
contains the receptors for steroid hormones
Question 54
Question
Membrane ion channels:
Answer
-
consist mainly of carbohydrates and lipids
-
have a specific structure for each ion species
-
for sodium may be blocked by tetrodotoxin
-
consist mainly of lipids
-
remain open as long as the activating signal is present
Question 55
Question
The speed of conduction of a nerve impulse can be determined by which of the following factors?
1. temperature 2. diameter of axon 3. stimulus frequency 4. myelin sheath; 5. stimulus strength
Answer
-
1,3, 5 and 4
-
1, 2 and 3
-
3 and 1
-
3 and 2
-
4, 2 and 1
Question 56
Question
The junction between one neuron and the next, or between a neuron and an effector is called:
Answer
-
a synapse
-
a dendrite
-
a neurotransmitter
-
a ventricle
-
none of the above
Question 57
Question
Which of the following blocks acetylcholine receptor sites causing muscle relaxation?
Answer
-
novocain
-
curare
-
nicotine
-
nerve gases
-
carbon monoxide
Question 58
Question
Transmission across a synapse is dependent on the release of?
Answer
-
neurotransmitters
-
synaptic vesicle
-
neurons
-
receptor proteins
-
hormones
Question 59
Question
Saltatory conduction:
Answer
-
occurs only in myelinated fibres
-
has a slower velocity in cold than in warm conditions
-
is faster than non-saltatory conduction in nerve fibres with diameters around 10 μm
-
transmits impulses with a velocity proportional to fibre diameter
-
all of them
Question 60
Question
An action potential in a nerve fibre:
Answer
-
occurs when its membrane potential is hyperpolarized to a critical level
-
is associated with a transient increase in membrane permeability to sodium
-
is associated with a transient decrease in membrane permeability to potassium
-
induces local response
-
has an amplitude which varies directly with the strength of stimulus