Week 3 Practice Questions
Sensory neurons ________. are multipolar, and carry impulses toward the CNS are bipolar, and carry impulses away from the CNS are multipolar, and carry impulses away from the CNS are pseudounipolar, and carry impulses toward the CNS
are pseudounipolar, and carry impulses toward the CNS
Depolarization of an axon is a positive feedback mechanism because ________. as more sodium diffuses into the axon, the more voltage-gated sodium channels open as more sodium diffuses into the axon, the more voltage-gated potassium channels open as more sodium channels open, the membrane potential decreases as more potassium channels open, the membrane potential decreases
as more sodium diffuses into the axon, the more voltage-gated sodium channels open
An electroencephalogram obtained from an adult who is thinking would probably display many ________ waves. theta beta alpha delta
beta
In order to prevent a patient from experiencing pain, local anesthetics must ________ in sensory neurons, which would prevent an action potential. bind to potassium channels inhibit the release of acetylcholine bind to calcium channels bind to sodium channels
bind to sodium channels
The ________ is a cerebral lobe that is involved in memory and integration of sensory information (mostly pain) with visceral responses. temporal insula parietal frontal
insula
The function of ________ is to link sensory stimuli with the appropriate motor responses. interneurons pseudounipolar neurons motor neurons bipolar neurons
interneurons
Damage to the ________ will cause a lack of motivation and sexual desire as well as deficient cognitive functions. medial temporal lobe hypothalamus amygdaloid body lateral prefrontal area
lateral prefrontal area
The membrane of resting nerve cells is more permeable to ________ ions than ________ ions. potassium; sodium sodium; potassium chloride; potassium calcium; potassium
potassium; sodium
Riding a bicycle with ease after years of not riding is an example of ________ memory. working episodic procedural semantic
procedural
What type of neurons are found in the precentral gyrus? Lower motor neurons Second-order sensory neurons Upper motor neurons Third-order sensory neurons
Upper motor neurons
A "word salad" speaking pattern occurs when ________. the angular gyrus is damaged spinal nerves are damaged the motor speech area is damaged Wernicke's area is damaged
Wernicke's area is damaged
Action potentials would be conducted most rapidly by ________. a 10 mm diameter unmyelinated axon a 40 mm diameter unmyelinated axon a 40 mm diameter myelinated axon a 10 mm diameter myelinated axon
a 40 mm diameter myelinated axon
Check all that apply as characteristics of oligodendrocytes. They are a type of neuroglia found in the PNS.T They would be affected by a demyelinating disease of the PNS. They can surround multiple axons in the CNS at the same time. They myelinate the cell bodies of neurons in the CNS. They contribute to the "white matter" of the brain.
They contribute to the "white matter" of the brain. They can surround multiple axons in the CNS at the same time.
Check all that apply. If you could modify an axon so that it transmits impulses faster than before, which of the following modifications should you make? - Decrease the diameter of the axon - Increase the diameter of the axon - Increase the myelination of the axon - Decrease the temperature in the body - Increase the temperature in the body - Increase the amount of voltage gated channels within the Schwann cells
- Increase the diameter of the axon - Increase the myelination of the axon - Increase the temperature in the body
Check all that apply as characteristics of myelinated axons. - Myelinated axons transmit nerve impulses via continuous conduction. - Myelinated axons transmit nerve impulses in the same manner as unmyelinated axons. - Myelinated axons utilize fewer voltage-gated channels than unmyelinated axons of the same length and diameter. - Myelinated axons are more energy efficient than unmyelinated axons. - Myelinated axons would be unaffected by diseases that attack the CNS.
- Myelinated axons utilize fewer voltage-gated channels than unmyelinated axons of the same length and diameter. - Myelinated axons are more energy efficient than unmyelinated axons.
There are ________ pairs of cranial nerves and ________ pairs of spinal nerves. 31; 12 12; 31 12; 25 15; 31
12; 31
The total percentage of blood flow to the body per minute that goes to the brain is ________. 30 15 20 25
15
The hypothalamus and the limbic system are involved in ________. aggression fear sex goal-directed behavior All of the choices are correct.
All of the choices are correct.
Which of the following are natural analgesics? Endorphins Enkephalins Dynorphins All of the choices are correct.
All of the choices are correct.
What structure connects Wernicke's area to the motor speech area? Corpus callosum Corpus striatum Arcuate fasciculus Angular gyrus
Arcuate fasciculus
Which division of the nervous system innervates involuntary effectors? Central nervous system Autonomic nervous system Somatic nervous system
Autonomic nervous system
Hyperpolarization in the postsynaptic cell is caused by ________. Both inhibitory postsynaptic potentials and movement of K+ out of the cell are correct. inhibitory postsynaptic potentials excitatory postsynaptic potentials movement of K+ out of the cell
Both inhibitory postsynaptic potentials and movement of K+ out of the cell are correct.
Cerebrospinal fluid is found ________. Both within the central canal and within the ventricles. within the central canal of the spinal cord within the olfactory bulbs within the ventricles of the brain
Both within the central canal and within the ventricles.
Which type of EEG pattern in an awake adult is indicative of brain damage? Alpha waves Beta waves Theta waves Delta waves
Delta waves
How do neurons code for a greater response? Greater amplitude of stimuli More active Na+/K+ pump Greater Na+ concentration gradient Increased frequency of stimuli
Increased frequency of stimuli
During an action potential ________. Na+ efflux causes depolarization K+ influx causes repolarization K+ influx causes after-hyperpolarization Na+ influx causes depolarization
Na+ influx causes depolarization
A drug that blocked ligand-gated ________ channels would prevent neuron ________. K+; depolarization Na+; depolarization Na+; hyperpolarization Ca2+; repolarization
Na+; depolarization
Clinical Investigation: Parkinson's Disease Read the overview and complete the interactivities that follow. A physician examined Henry, a 66-year-old man, because he displayed symptoms of Parkinson's disease: resting tremor, muscle rigidity, and bradykinesia (slowness in the initiation and continuation of movement). This made it difficult for Henry to perform daily tasks such as getting dressed, bathing, and many other activities. Further physical examination and a thorough history, together with an MRI to rule out alternative possibilities, confirmed the diagnosis. The physician placed Henry on a dopamine agonist that can cross the blood-brain barrier, and said that this could be supplemented later by levodopa, an MAO inhibitor, anticholinergics, and other medications. A drug must be able to cross the blood-brain barrier to be effective in treating brain disorders such as Parkinson's disease. Dopamine agonist drugs enter the brain and stimulate dopamine receptors on postsynaptic neurons. This helps to stimulate those neurons of the basal nuclei (basal ganglia) that are normally activated by dopaminergic neurons of the nigrostriatal dopamine system. Dopamine is derived from L-dopa (le
Neural tracts that release dopamine and are involved in motor control Tyrosine Monoamine oxidase Basal nuclei
Using the numbers provided, match the technique names for visualizing brain function with the description of the technique. SPECT MEG fMRI CT EEG PET
SPECT - Increased neuronal activity increases cerebral blood flow and is measured using emitters of single photons. MEG - Neuronal magnetic activity is measured using magnetic coils and mathematical plots. fMRI - Increased neuronal activity increases cerebral blood flow and oxygen consumption in local areas. CT - A number of x-ray beams are sent through the brain or body region and are sensed by numerous detectors; a computer uses information to produces images. EEG - Neuronal activity is measured as maps with scalp electrode. PET - Increased neuronal activity increases cerebral blood flow and metabolite consumption in local areas.
REM sleep is unique from other stages in that ________. it causes ideal rest, without emotional activation learning from activities during the day occurs breathing and heart rate mimic the patterns during waking hours memory consolidation can occur
breathing and heart rate mimic the patterns during waking hours
The famous patient "H.M." could not remember events that occurred after his memory was damaged after he had brain surgery to treat his epilepsy. He retained his perceptual and motor skills but lost his memory of new facts and events. Thus, H.M.'s deficit was in ________. declarative or explicit memory nondeclarative or explicit memory nondeclarative or implicit memory declarative or implicit memory
declarative or explicit memory
Damage to the temporal lobe of the cerebrum would have the greatest impact on ________. hearing distinguishin between different somatic sensations vision voluntary skeletal muscle contraction
hearing
Ablation of the ________ in the midbrain would impair the ability to respond to sounds. red nucleus substantia nigra medial colliculi inferior colliculi
inferior colliculi
Being able to recognize the face of a schoolmate at your 30-year reunion would be a function of the ________. occipital lobe inferior temporal lobes anterior frontal lobes medial temporal lobes
inferior temporal lobes
The majority of the fibers of the pyramidal tracts decussate in the ________. medulla oblongata spinal cord basal nuclei midbrain
medulla oblongata
A dysfunction of ________ neurons would limit the ability to learn from and mimic the dance steps of an instructor. mirror neurons interneurons sensory neurons motor neurons
mirror neurons
Alzheimer disease is ________. not associated with or mediated by any lifestyle changes associated with excessive accumulation of cortical neurons, preventing proper synaptic transmission in the brain a genetic disease with a clinical course similar to Parkinson's disease multifactorial, involving potential changes in enzyme, protein and lipid activity in the brain.
multifactorial, involving potential changes in enzyme, protein and lipid activity in the brain.
The gap of exposed axon in the myelin sheath is the ________. white matter neurilemma sheath of Schwann node of Ranvier
node of Ranvier
The myelin sheaths of CNS neurons are produced by ________. leukocytes ependymal cells Schwann cells oligodendrocytes
oligodendrocytes
Unlike chemical synapses, electrical synapses ________. allow communication between cells with larger distances between the membranes are not dependent on the movement of ions across a plasma membrane are the method of connection between adjacent neurons provide adjacent cells with the ability to act in a coordinated fashion
provide adjacent cells with the ability to act in a coordinated fashion
Muscarinic ACh receptors are found in all of the following locations EXCEPT ________. smooth muscle skeletal muscle cardiac muscle glands
skeletal muscle
The minimum depolarization needed to open Na+ gates is called the ________. repolarization refractory period all-or-none law threshold
threshold
Ion channels that open in response to depolarization are called ________. potential-gated channels stimulation-gated channels ion-gated channels voltage-gated channels
voltage-gated channels
The average resting membrane potential of an axon is ________. −70mV −85mV 0 mV +30mV
−70mV