Human Anatomy and Physiology II
Exam 1, Version 3 - Feb. 24, 1995
Dr. Chabot
Multiple Choice (@2 points): Circle the letter of the one best answer. GOOD LUCK!
Answer only 30 out of 33! The first 30 answered will be graded.
1. Assume that an axon is artificially stimulated about halfway along its length. Which of the following will occur?
A. Negative organic (A-) ions move out of the cytoplasm to the outside of the axon.
B. The impulse may travel in both directions.
C. Sodium ions cross the membrane out of the cytoplasm; potassium ions move across the membrane into the cytoplasm of the axon.
D. Negative feedback loop will occur causing Na+ channels to close.
2. Which of the following glial cells is not found in the CNS?
A. oligodendrocytes
B. schwann cells
C. astrocytes
D. ependymal cells
3. Postsynaptic potentials:
I. can be summed.
II. are graded.
III. are conducted decrementally (decrease in amplitude with distance).
IV. usually last much longer than action potentials.
A. I and III only
B. II and IV only
C. I, II, and III only
D. I, II, III, and IV
4. Which of the following is not true about an action potential in a nerve cell?
A. It is normally caused by a sudden increase in sodium-potassium pump activity.
B. It is associated with a sudden increase in sodium permeability (gates open) and a somewhat slower increase in potassium permeability (gates open).
C. It can occur in a neuron because of the unequal distribution of ions across the membrane.
D. It does not vary in amplitude with the strength of the stimulus used to trigger it.
5. When an inhibitory neurotransmitter combines with a receptor site on a postsynaptic membrane, the first event that is triggered is an:
A. influx (inward flow) of potassium ions.
B. influx of sodium ions.
C. influx of chloride ions.
D. efflux (outward flow) of potassium ions.
6. If a series of post synaptic potentials is not great enough to surpass the threshold level at the axon hillock, the strength of the action potential generated will be:
A. zero.
B. proportional to the strength of the post synaptic potentials.
C. inversely proportional to the strength of the post synaptic potentials.
D. the same, no matter what the strength of the post synaptic potentials
7. Approximately 1 msec after an axon is strongly depolarized:
A. the K+ channels close.
B. the Na+ channels open.
C. the Na+ channels are inactivated.
D. the K+ channels are inactivated.
8. Neurotransmitters are produced and packaged in the soma (cell body) and "get" to the terminals via:
A. simple diffusion
B. axonal transport
C. channels opening and closing
D. all of the above
9. Which of the following structures are involved in processing visual information?
A. The superior colliculus, the lateral geniculate and part of the temporal cortex
B. The superior colliculus, the medial geniculate and part of the occipital cortex.
C. The superior colliculus, the lateral geniculate and part of the occipital cortex.
D. The superior colliculus, the lateral geniculate and part of the frontal cortex.
10. Hyperpolarization of the neuronal membrane may be produced by any factor that:
A. increases the membrane's permeability to sodium ions.
B. decreases the membrane's permeability to sodium ions.
C. stimulates the sodium-potassium pump.
D. increases the membrane's permeability to potassium ions.
11. Ion pumps are important for which of the following?
A. long term maintenance of the resting potential
B. short term maintenance of the resting potential
C. long term maintenance of the action potential
D. short term maintenance of the action potential
12. Where would you look in the spinal cord for the cell bodies of sensory neurons?
A. ventral gray horn
B. lateral gray horn
C. white matter
D. dorsal root ganglion
13. The ventral root of each spinal nerve:
I. carries sensory information from peripheral receptors.
II. contains the processes (axons/dendrites) of nerve cells located in ganglia.
III. contains motor neuron cell bodies.
A. I only
B. II only
C. III only
D. none of the above
14. In the crossed extensor reflex initiated on the right side, the motor neurons of the left triceps will:
A. not be affected
B. be stimulated by excitatory interneurons
C. be inhibited by inhibitory interneurons
D. be inhibited by neurons of the thalamus
15. Which of the following tissue(s) are involved in producing CSF?
A. dura mater and pia mater
B. dura mater and arachnoid
C. pia mater
D. pia mater and arachnoid
16. Which of the following brain parts is correctly matched with a function it helps control?
A. frontal lobes of cerebrum-vision
B. occipital lobes of cerebrum -motor movements
C. temporal lobes of cerebrum -audition (hearing)
D. "strip" of cerebrum adjacent to central sulcus- "higher" thinking, calculus, etc.
17. The basal ganglia are involved in:
A. interpreting sensory information
B. relaying sensory information
C. relaying motor information
D. emotions and anxiety
18. Glial cells:
A. are found in higher numbers in the central nervous system than even neurons
B. function only to insulate axons
C. are found only in the gray matter of spinal cords
D. are also known as "ghost" cells
19. Which of the following would be a safe place in a adult to give a spinal tap?
A. T6
B. T10
C. T12
D. L1
E. L4
20. TEA, a neurotoxin, blocks:
A. the active transport pump which maintains ion gradients
B. K+ channels
C. Na+ channels
D. Cl- channels
21. Sodium and potassium ion channel selectivity appears to be based on:
A. different charges on the ions
B. channel recognition factor
C. the fact that one is a salt
D. size differences between ions
22. Action potentials travel faster in myelinated axons because:
A. myelin acts as a super conductor and speeds up the conduction
B. the action potentials jumps (travels very fast) between the nodes of Ranvier
C. the myelin greatly increases the resistance of the axonal cytoplasm
D. myelin acts as an enzyme which speeds up (catalyzes) the reaction
23. Sensory information from receptors in the body travels up the spinal cord to the brain along the:
A. spinocerebellar tract
B. rubrospinal tract
C. corticospinal tract
D. none of the above
24. Inhibitory post synaptic potentials (EPSPs) occur in neuronal post synaptic membranes when:
A. Na+ flows into the post synaptic cell
B. K+ flows into the post synaptic cell
C. Ca++ flows into the post synaptic cell
D. Cl - is freely distributed across the membrane
25. Two neurons X and Y have excitatory input onto neuron Z. The terminal of neuron X is located 1.5 mm from the axon hillock of neuron Z, while the terminal of neuron Y is located 3.0 mm from the hillock. If, at different times, both X and Y stimulate neuron Z at the same rate and cause the same amount of post-synaptic depolarization at the terminals:
A. Neuron X will have a lesser chance of causing neuron Z to fire
B. Neuron Y will have a lesser chance of causing neuron Z to fire
C. They will both cause neuron Z to fire since action potentials are all-or-none
D. They both have an equal chance to cause neuron Z to fire.
26. The effects that a neurotransmitter will have on the postsynaptic membrane is determined primarily by:
A. the chemical structure of the transmitter
B. the type of pre-synaptic cell
C. the types of enzymes located in the synapse
D. the structure of the post-synaptic receptor
27. Cerebrospinal fluid performs all of the following functions except:
A. helps to absorb impacts
B. helps to remove metabolic wastes
C. helps to buoy and support the brain
D. helps the brain to maintain its resting potential
28. Which of the following is not a branch of the brachial plexus?
A. median
B. radial
C. ulnar
D. axillary
E. humeral
29. At rest, what percent of our oxygen intake is consumed by the brain?
A. 10%
B. 20%
C. 30%
D. 50%
30. The medulla oblongata serves all the following functions except:
A. regulates respiratory functions
B. regulates heart rate
C. regulates liver functions
D. regulates the diameter of arterioles
31. The cerebrum does not appear to function to:
A. serve as a site for memory storage
B. serve as a site for "higher thought" and analysis
C. interpret sensory information
D. regulate rate of heart beat
32. Parkinson's disease is a disease of:
A. the medulla oblongata
B. the thalamus
C. the hypothalamus
D. the basal ganglia
33. The hypothalamus does not help to regulate:
A. motor movements
B. body temperature
C. balance of ions in the blood
D. balance of water in the blood
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Complete the following sentences with the most appropriate (one) word (@ 2 points).
Choose 10 out of 12 only.
1. The _____________ nerve innervates the skin of the hands and the muscles of the hands and forearm .
2. The disease that preferentially attacks and kills lower motor neurons is _________________.
3. There are approximately _______ pairs of spinal nerves.
4. The fluid filled center of the spinal cord is the _________________.
5. A __________________ is a predictable involuntary response to a stimulus.
6. Descending motor information descends in the spinal cord in the _______________tract.
7. The part of the brain that is involved in keeping the cerebrum "aware" and awake is the ____________.
8. Proteins which allow ions to pass through membranes only after they are stimulated by chemical messengers are called ________________.
9. The (specific) chemical messenger at the neuromuscular junction is known as a __________________.
10. The ionic basis for the resting and action potentials was first worked out in the _________ giant axon.
11. The additive effects of EPSPs caused by the same synapse is known as _________________ summation.
12. ______________ EEG waves are usually seen in an awake adult at rest.
Essay/Short Answer (@ 10 pts). Answer only 2 of the following 3. The first 2 answered will be graded.
1) Draw and label one or two graphs showing the principles of temporal and spatial summation. Hint: You should probably also include a drawing that indicates where the inputs are located on the post-synaptic cell.
2) Draw and label a diagram which shows the important structures/cells which mediate (underlie) the patellar tendon reflex.
3) List structures/areas in the brainstem and the cerebrum and their primary functions.