SAMPLE TEST questions Unit 1 Flashcards
The process by which an organism maintains itself in a relatively stable or constant condition and within certain physiological limits is called:
metabolism.
positive feedback
homeostasis
growth
homeostasis
Negative feedback results when a/an _______ in the output of a system causes a/an _______in the input of the system.
increase; increase
increase; decrease
decrease; decrease
All of the above can be true under differing circumstances.
increase; decrease
________ neurons carry information toward the Central Nervous System, and ________ neurons carry information away from the Central Nervous System.
Autonomic; somatic
Somatic; autonomic
Afferent; efferent
Efferent; afferent
Afferent; efferent
According to Fick’s Law of Diffusion, the rate of diffusion is directly related to:
the concentration gradient
molecular weight
temperature
both the concentration gradient and temperature
both the concentration gradient and temperature
The two major subdivisions of the Efferent branch of the Peripheral Nervous System are:
the Autonomic and Somatic
the Sensory and Motor
the Central and Autonomic
the Parasympathetic and Sympathetic
the Autonomic and Somatic
Read the following two statements and determine the most appropriate assessment.
A: Rate of diffusion at a temperature of 37o C.
B: Rate of diffusion at room temperature (20o C).
options:
A is approximately equal to B
B is greater than A.
A is greater than B
A is greater than B
In the resting cell membrane potential, ________ opposes the outward movement of potassium ions.
an electrical gradient
a concentration gradient
both a and c are corrent
an active transport mechanism
an electrical gradient
How is the resting membrane potential of -70 mV (millivolts) best interpreted?
options:
The potential outside of the membrane is -70 mV.
The potential outside of the membrane is 70 mV more negative than the inside.
The potential inside of the membrane is 70 mV more negative than the outside.
The potential inside of the membrane is -70 mV.
The potential inside of the membrane is 70 mV more negative than the outside.
A stimulator is used to apply a stimulus to a single neuron. The threshold stimulus is determined to be 3 volts. If a stimulus of 4 volts is applied, the resulting action potential will be ________ the action potential observed on the same neuron given a stimulus of 3 volts.
No action potential will occur under these circumstances.
the same as
less than
greater than
the same as
Which of the following cell types can conduct action potentials?
- smooth muscle cells
- cardiac muscle cells
- neurons
- skeletal muscle cells
3 and 4
1, 2, 3, and 4
3 only
2, 3 and 4
All the above
During repolarization of the neuronal membrane:
potassium ions rapidly move to the outside of the cell
sodium ions rapidly move to the inside of the cell.
potassium ions rapidly move to the inside of the cell.
sodium ions rapidly move to the outside of the cell from the inside.
potassium ions rapidly move to the outside of the cell
Read the the following two statements and detemine the most appropriate assessment.
A. Concentration of Na+ in cytoplasm.
B. Concentration of Na+ in extracellular fluid.
options:
A is greater than B
B is greater than A
A is approximately equal to B
B is greater than A
A single muscle fiber:
options:
does not require external nervous stimulation to initiate its contractile activity.
will not contract when stimulated by a subthreshold stimulus.
always contracts independently of other fibers.
shows an increasing force of contraction with increasing stimulus strength.
will not contract when stimulated by a subthreshold stimulus.
Skeletal muscles are innervated by:
autonomic motor neurons.
somatic motor neurons.
sympathetic pre-ganglionic neurons.
both somatic and autonomic motor neurons.
somatic motor neurons.
What is the appropriate order for the following events that occur during excitation-contraction coupling?
1 - Calcium is released from the sarcoplasmic reticulum.
2 - Acetylcholine binds to receptors.
3 - Myosin binds to actin.
4 - Action potentials travel along the sarcolemma.
5 - Myosin head flexes.
options:
2, 4, 1, 3, 5
1, 4, 5, 3, 2
4, 2, 3, 5, 1
2, 1, 4, 5, 3
2, 4, 1, 3, 5
Multiple motor unit summation occurs as a result of increasing the _____ of stimuli applied to a skeletal muscle, while wave summation is the result of increasing the _____ of stimuli.
option:
duration; frequency
voltage; frequency
frequency; voltage
voltage; duration
voltage; frequency
Which of the following is most important in allowing muscle tone to be maintained for long periods of time (such as in holding the head erect)?
options:
the latent period
asynchronous firing of motor units
multiple motor unit summation
wave summation
asynchronous firing of motor units
Read the the following two statements and detemine the most appropriate assessment.
A. The number of skeletal muscle fibers contracting in a motor unit when its motor neuron receives a supra-maximal stimulus.
B. The number of skeletal muscle fibers contracting in a motor unit when its motor neuron receives a threshold stimulus.
options:
A is greater than B
A is approximately equal to B
B is greater than A
A is approximately equal to B
the Enteric Nervous System
the Sympathetic Nervous System
the Somatic Nervous System
the Parasympathetic Nervous System
the Parasympathetic Nervous System
The neurotransmitter released from pre-synaptic neurons in the sympathetic ganglia is ________, while the neurotransmitter released from sympathetic post-ganglionic neurons is ________.
options:
norepinephrine; epinephrine
acetylcholine; epinephrine
acetylcholine; acetylcholine
acetylcholine; norepinephrine
acetylcholine; norepinephrine
Adding ______, a cholinergic antagonist, to an isolated section of visceral smooth muscle results in ______ force of contraction.
options:
pilocarpine, an increased
pilocarpine, no change in the
atropine, no change in the
atropine, a decreased
atropine, no change in the
Knowing that epinephrine is released during exercise, you would expect the intestinal smooth muscle to:
options:
increase inherent rhythmicity.
have no effect on the smooth muscle, but increase the absorption of nutrients.
decrease activity to redistribute blood flow to exercising muscles.
increase activity to supply needed energy to the exercising muscles.
decrease activity to redistribute blood flow to exercising muscles.
Single unit smooth muscle will contract in response to:
options:
action potentials passed from adjacent smooth muscle cells through gap junctions.
action potentials from neurons innervating the muscle.
all of the above
stretch of the muscle fibers.
all of the above
Read the the following two statements and detemine the most appropriate assessment.
A. The force of contraction of an intestinal smooth muscle segment when atropine is added to the surrounding bath.
B. The force of contraction of an intestinal smooth muscle segment when epinephrine is added to the surrounding bath.
options:
A is approximately equal to B
B is greater than A
A is greater than B
A is greater than B
