QUIZ 3
Correct answers marked in bold.
Monday, Nov. 18th 8:00-9:00 AM
1. Which of the following statements is true?
A) Thermoregulation is a characteristic of endotherms but not ectotherms.
B) Thermoregulation is a characteristic of homeotherms but not endotherms.
C) Thermoregulation is a characteristic of ectotherms but not endotherms.
D) Thermoregulation is a characteristic of ectotherms but not homeotherms.
2. In a mammal, which of the following does not aid in the retention of body heat?
A) raising fur
B) sweating
C) vasoconstriction of cutaneous blood vessels
D) subcutaneous fat layer
3. What is the appropriate name for a neuron that only exchanges information with other neurons?
A) Schwann cell
B) sensory neuron
C) motor neuron
D) interneuron
4. In the neuronal circuit responsible for the knee-jerk reflex, where do the sensory neurons and motor neurons synapse with one another?
A) spinal cord
B) nerve connecting spinal cord to muscles
C) quariceps muscle
D) flexor muscle
5. The transport of ions through an ion channel is affected by all of the following except
A) open state of the ion pore
B) intracellular supply of ATP
C) electrical membrane potential
D) concentration of that ion species inside and outside the cell
Friday, Nov. 22nd 8:00-9:00 AM
1. Which of the following statements is not generally true for both endotherms and ectotherms?
A) Digestion and metabolism give rise to body heat
B) If wet skin is exposed to air, evaporation will have a cooling effect.
C) In cold environments, body heat is lost from the body surface .
D) Rate of heat production can be increased to raise body temperature.
2. Which of the following is the most accurate description of the resting potential in an animal cell?
A) more positive than the Na+ equilibrium potential
B) slightly negative to the Na+ equilibrium potential
C) slightly positive to the K+ equilibrium potential
D) more negative than the K+ equilibrium potential
3. What is the appropriate name for a neuron that synapses with a muscle cell?
A) Schwann cell
B) sensory neuron
C) motor neuron
D) interneuron
4. In the neuronal circuit responsible for the knee-jerk reflex, where are the dendrites of the motor neuron located?
A) spinal cord
B) nerve connecting spinal cord to muscles
C) quadriceps muscle
D) flexor muscle
5. Which of the following is primarily responsible for the initial or 'rising' phase of an action potential?
A) K+ ions flow into the cytoplasm
B) K+ ions flow out of the cytoplasm
C) Na+ ions flow into the cytoplasm
D) Na+ ions flow out of the cytoplasm
Friday, Nov. 22nd 9:00-10:00 AM
1. How does sweating reduce body temperature?
A) conduction
B) convection
C) evaporation
D) radiation
2. What is the appropriate name for a neuron that transduces an external stimulus into an electrical signal?
A) Schwann cell
B) sensory neuron
C) motor neuron
D) interneuron
3. Electrical signals are transmitted by how many synapses between the beginning and end (starting with the 'tap' and ending with the contraction of the quadriceps muscle) of the knee-jerk reflex? [Note: do not include the inhibition of the flexor muscle in your answer.]
A) none
B) one
C) two
D) three
4. In an animal cell at resting potential, the net flow of Na+ ions through the Na-channels of the cell membrane would be
A) zero
B) from cytoplasm into extracellular fluid
C) from extracellular fluid into cytoplasm
D) equal and opposite to Na+ equilibrium potential
5. Which part of a neuron contains the nucleus?
A) axon
B) dendrite
C) synapse
D) cell body
Friday, Nov. 22nd 10:00-11:00 AM
1. In a mammal, which of the following would not aid in the loss of excess body heat?
A) bathing in cool water
B) sweating
C) vasodilation of cutaneous blood vessels
D) raising the fur
2. Which part of a neuron carries signals to other neurons?
A) cell body
B) axon
C) dendrite
D) myelin
3. In animal cells, the Na/K pump is responsible for transporting ions in which direction(s)?
A) Na+ into cell; K+ into cell
B) Na+ into cell; K+ out of cell
C) Na+ out of cell; K+ into cell
D) Na+ out of cell; K+ out of cell
4. In the neuronal circuit responsible for the knee-jerk reflex, where does the sensory neuron transduce the stimulus (stretch) into an electrical signal?
A) spinal cord
B) nerve connecting spinal cord to muscles
C) quadriceps muscle
D) flexor muscle
5. If a cell membrane is at the K+ equilibrium potential, the net flow of K+ ions through the K-channels of that membrane would be
A) zero
B) from cytoplasm into extracellular fluid
C) from extracellular into fluid cytoplasm
D) variable, depending upon supply of ATP
Friday, Nov. 22nd 11:00-12:00 Noon
1. Which of the following structures does not provide thermal insulation of the body surface?
A) subcutaneous fat
B) sweat glands
C) fur
D) feathers
2. Which of the following statements is generally true for both endotherms and ectotherms?
A) Digestion and metabolism give rise to body heat.
B) Rate of heat production can be increased to raise body temperature.
C) Body has adaptations to retard heat loss to the environment.
D) Body temperature is always close to the temperature of the environment.
3. What is the appropriate name for a neuron that synapses with a gland cell?
A) Schwann cell
B) sensory neuron
C) motor neuron
D) interneuron
4. Why does the opening of Na-channels cause the cell membrane to depolarize during an action potential?
A) sodium ions enter the cell and make the cytoplasm more positive
B) sodium ions enter the cell and make the cytoplasm more negative
C) sodium ions leave the cell and make the cytoplasm more positive
D) sodium ions leave the cell and make the cytoplasm more negative
5. Which of the following is essential for the transport of ions by the Na/K pump?
A) concentration of sodium ions higher inside the cell than outside
D) concentration of potassium ions higher outside the cell than inside
B) supply of ATP in the cytoplasm
C) negative electrical membrane potential
NOTE: this is how the question was written on the quiz sheet. The correct answer 'B' is in the position normally occupied by the answer 'C'. As a consequence, credit will be given for EITHER of these two answers (but not 'A' or 'D'). Credit for answering 'C' can not be added to the quiz scores until next week, when the original bubblesheets are returned to us. My apologies for the confusion.