WSU Biology 251 Exam 1 (50 Questions with Verified
Answers) Latest Update.
Which of the following statements about homeostasis is FALSE?
a.) Homeostasis is the maintenance of the internal environment
b.) The organ systems work together to maintain homeostasis
c.) Illness can result if homeostasis is disrupted
d.) The primary mechanism to maintain homeostasis is positive feedback
e.) The extracellular fluid is maintained in a state compatible for life - ANS d.) The
primary mechanism to maintain homeostasis is positive feedback
What type of cell produces myelin sheaths around axons of neurons in the central
nervous system? - ANS oligodendrocyte
In a neuron, where are voltage-gated calcium channels located? - ANS axon terminal
The body fluid compartment with a high potassium and protein concentration is
_________. - ANS intracellular fluid
In most homeostasis mechanisms, a ________ detects a change in a regulated
variable and sends that information to a (n) _________ which relays signals to a (n)
_________. - ANS sensor; integrating; center; effector
The function of a second messenger system is to - ANS amplify the response of the
first messenger
Parasympathetic preganglionic neurons release the neurotransmitter _______;
sympathetic preganglionic neurons release the neurotransmitter ______. - ANS
acetylcholine; acetylcholine
The electrochemical gradient for sodium across the membrane is such that the net
flux for sodium movement is directed ________, thereby causing the cell's membrane
potential to become more _______. - ANS inward; positive
Which of the following cells would have a greater electrical attraction for sodium ions
to enter the cell?
a.) cell with membrane potential =-70mV
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, b.) cell with membrane potential = 0mV
c.) cell with membrane potential =-90mV
d.) cell with membrane potential =+20mV
e.) cell with membrane potential =-50mV - ANS c.) Cell with membrane potential =-
90mV
As the number of receptors on the cell membrane decreases, the response of the
target cell will ________. - ANS decrease
Which of the following transport mechanisms requires energy? - ANS both primary
and secondary active transport
True or False. Synaptic communication to a skeletal muscle cell via a somatic motor
neuron can be excitatory or inhibitory - ANS False
Based solely upon its negative electrical charge, the inside of a typical cell will tend to
attract extracellular _____ to move inward - ANS captions
Parasympathetic postganglionic neurons release the neurotransmitter ________;
sympathetic postganglionic neurons release the neurotransmitter ________. - ANS
acetylcholine; norepinephrine
Much evidence suggests that clinical depression is associated with deficiencies in the
biogenic amines serotonin and norepinephrine. If this is true and the body has
reduced concentrations of these amines, one might predict the body would _____ in
order to adapt to these lowered levels. - ANS up-regulate receptors for these
messengers
What is a molecule that is similar in structure to a messenger and binds with that
messenger's receptor to stimulate a similar response from the target cell? - ANS
agonist
Which of the following best describes the function of myelin? - ANS increase action
potential conduction velocity
When molecules are passively transported across a membrane, the direction of their
movement is dictated by the molecule's tendency to move ________. - ANS from
higher concentration to lower concentration
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Answers) Latest Update.
Which of the following statements about homeostasis is FALSE?
a.) Homeostasis is the maintenance of the internal environment
b.) The organ systems work together to maintain homeostasis
c.) Illness can result if homeostasis is disrupted
d.) The primary mechanism to maintain homeostasis is positive feedback
e.) The extracellular fluid is maintained in a state compatible for life - ANS d.) The
primary mechanism to maintain homeostasis is positive feedback
What type of cell produces myelin sheaths around axons of neurons in the central
nervous system? - ANS oligodendrocyte
In a neuron, where are voltage-gated calcium channels located? - ANS axon terminal
The body fluid compartment with a high potassium and protein concentration is
_________. - ANS intracellular fluid
In most homeostasis mechanisms, a ________ detects a change in a regulated
variable and sends that information to a (n) _________ which relays signals to a (n)
_________. - ANS sensor; integrating; center; effector
The function of a second messenger system is to - ANS amplify the response of the
first messenger
Parasympathetic preganglionic neurons release the neurotransmitter _______;
sympathetic preganglionic neurons release the neurotransmitter ______. - ANS
acetylcholine; acetylcholine
The electrochemical gradient for sodium across the membrane is such that the net
flux for sodium movement is directed ________, thereby causing the cell's membrane
potential to become more _______. - ANS inward; positive
Which of the following cells would have a greater electrical attraction for sodium ions
to enter the cell?
a.) cell with membrane potential =-70mV
Page 1 of 6
, b.) cell with membrane potential = 0mV
c.) cell with membrane potential =-90mV
d.) cell with membrane potential =+20mV
e.) cell with membrane potential =-50mV - ANS c.) Cell with membrane potential =-
90mV
As the number of receptors on the cell membrane decreases, the response of the
target cell will ________. - ANS decrease
Which of the following transport mechanisms requires energy? - ANS both primary
and secondary active transport
True or False. Synaptic communication to a skeletal muscle cell via a somatic motor
neuron can be excitatory or inhibitory - ANS False
Based solely upon its negative electrical charge, the inside of a typical cell will tend to
attract extracellular _____ to move inward - ANS captions
Parasympathetic postganglionic neurons release the neurotransmitter ________;
sympathetic postganglionic neurons release the neurotransmitter ________. - ANS
acetylcholine; norepinephrine
Much evidence suggests that clinical depression is associated with deficiencies in the
biogenic amines serotonin and norepinephrine. If this is true and the body has
reduced concentrations of these amines, one might predict the body would _____ in
order to adapt to these lowered levels. - ANS up-regulate receptors for these
messengers
What is a molecule that is similar in structure to a messenger and binds with that
messenger's receptor to stimulate a similar response from the target cell? - ANS
agonist
Which of the following best describes the function of myelin? - ANS increase action
potential conduction velocity
When molecules are passively transported across a membrane, the direction of their
movement is dictated by the molecule's tendency to move ________. - ANS from
higher concentration to lower concentration
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