AP Practice Exams 3
1) Extracellular Ca2+ enters terminal and binds to sensor protein in the cytoplasm2) Exocytosis of neurotransmitter into synaptic cleft3) Action potential reaches axon terminal4) Ca2+-protein complex stimulates fusion of the docked synaptic vesicle with the plasma membrane5) Voltage-gated Ca2+ channels open
3, 5, 1, 4, 2
Place the following parts of a reflex arc in the correct order beginning with the sensory receptor. (1) motor neuron (2) interneuron (3) effector (4) sensory neuron (5) sensory receptor
5, 4, 2, 1, 3
A patient suffering from nerve damage is having trouble maintaining posture and moving his vertebral column. Which component of the nearby spinal nerves has been damaged?
Dorsal Rami
Identify the statement that best differentiates gray matter and white matter
Gray matter consists of cell bodies and dendrites, whereas white matter consists mostly of myelinated axons.
Cerebral Cortex
Gray matter on the outer surface of the cerebrum
Temporal Lobe Function
Hearing, memory, smell
Subthalamus
Immediately inferior to the thalamus; involved in controlling motor functions
In an adult, the spinal cord extends down the vertebral column to the level of which vertebrae?
L1-L2
Thalamus
Largest part of the diencephalon; the sensory relay center of the brain relays sensory nerve signals to the cerebrum
brainstem parts superior to inferior
Midbrain Pons Medulla Oblongata
Hypothalamus
Most inferior portion of the diencephalon; contains mammillary bodies; controls endocrine system Regulates secretion of pituitary hormones involved in the sensation of sexual pleasure coordinates autonomic nervous system activity
Parietal Lobe Function
Most sensory input other than smell, taste, hearing, and vision
Frontal Lobe Function
Personality, Decision making, Aggression, mood, Voluntary motor function
Identify the correct sequence of structures involved in the passage of information across a chemical synapse.
Presynaptic terminal; synaptic cleft; postsynaptic membrane
__________ summation occurs when multiple action potentials arrive simultaneously at two different presynaptic terminals that synapse with the same postsynaptic neuron cell body.
Spatial
Cerebrospinal fluid from the ____________ passes through the ____________, where it enters the venous circulation.
Subarachnoid space; arachnoid granulations
Epithalamus
Superior and posterior to the thalamus; contains the pineal gland Pineal gland involved in sleep wake cycle and biorhythms
Parts of the Diencephalon
Thalamus, subthalamus, epithalamus, hypothalamus
For each ATP molecule used, the sodium-potassium pump transports
two K+ into the cell and three Na+ out of the cell.
When a doctor gives a patient epidural anesthesia, they are inserting a needle between which two structures?
body of the vertebrae and dura mater
Spinal nerves C5-T1 make up the ____________ plexus.
brachial
motor speech area of the brain
broca
Dermatome maps are important clinically because they
can be used to help locate nerve damage
In the cerebrum, the basal nuclei are the __________ nucleus, which is described as having a tail, and the ________ nucleus, which is described as being lens-shaped.
caudate; lentiform
association fibers
connect areas of the cerebral cortex within the same hemisphere
commissural fibers
connect one cerebral hemisphere to another
projection fibers
connect the cerebrum to other parts of the brain and spinal cord
Homeostatic regulation of receptor levels often forms the basis of addiction. In Ralph's case the increased release of dopamine caused a progressive
decrease in dopamine receptor numbers in dopaminergic postsynaptic membranes.
The ____________ extends laterally from the spinal cord and attaches to the dura mater, helping to limit lateral movement of the spinal cord.
denticulate ligament
Most synapses are thought to employ more than one neurotransmitter, and synapses may be located in close proximity to each other. What receptor property prevents one neurotransmitter (e.g., norepinephrine) from activating a nearby receptor for another neurotransmitter (e.g., acetylcholine)?
differences in receptor structure
A man in a car accident cannot feel his left leg but is able to contract the muscles there. Which component of the relevant spinal nerves or spinal cord region has been damaged?
dorsal root
The spinal cord extends from the level of the __________ to the level of the __________.
foramen magnum; second lumbar vertebra
Groups of related nerve cell bodies located outside of the central nervous system are called __________.
ganglia
Structures called ___________ are involved in electrical synapses.
gap junctions
The deepest of the cerebral lobes, the ______ receives taste sensory input.
insula
Blood is supplied to the brain through the ____________, which ascend to the head along the anterior-lateral side of the neck, as well as the _____________, which ascend along the posterior side of the neck.
internal carotid arteries; vertebral arteries
These arteries include the __________ _______ arteries that enter the cranium via the ________ arteries, and the _______ ________, which enter the cranium by way of the _______ _______
internal carotid; carotid canals; vertebral; foramen magnum
Ventral rami of some spinal nerves join with each other to form a __________.
plexus
Each half of the gray matter is organized into the ____________ horns.
posterior, anterior, lateral
The ventricles arise from __________ during embryonic development.
pouch cavities
Which of the following is not a common feature of the cerebrum and cerebellum?
presence of one or more ventricles
The ____________ of a neuron release(s) neurotransmitters.
presynaptic terminals
connects cerebrum to brainstem forms the internal capsule
projection tract
Major branches of a spinal nerve are called __________.
rami
For a typical neuron, what limits the maximal frequency attainable of action potentials moving down an axon?
refractory period
The blood-brain barrier functions to
regulate the movement of materials from blood to the brain
pons function
relays information between cerebrum and cerebellum
Cerebrospinal fluid fills in the space between the
arachnoid mater and pia mater
Communication within the cerebral cortex in the same hemisphere
association tract
Along myelinated axons of the peripheral nervous system, ion currents must cross the plasma membrane of the neuron
at nodes of Ranvier
A student observes gray tissue in a preserved section of a human brain. Which of the following might he be looking at?
basal nuclei
fourth ventricle
base of the cerebellum
Additionally, the _______ artery lies on the ventral side of the pons.
basilar
The three columns of the white matter are the ___________ columns.
ventral, dorsal, and lateral
What do the cavities of the neural tube become in the adult brain?
ventricles
midbrain function
visual reflex center
if a blockage forms in the cerebral aqueduct, where will CSF back up first?
third ventricle
Identify the only spinal nerve that does not have a specific cutaneous sensory distribution.
C1
The __________ enlargement of the spinal cord is the location where nerves that supply the upper limbs enter and leave the spinal cord, and the __________ enlargement is the location where nerves that supply the lower limbs enter and leave the spinal cord.
Cervical; Lumbosacral
Which of the following would be a likely result of damaging the musculocutaneous nerve?
Difficulty flexing the shoulder
Which of the following would be a likely result of severing the tibial and common fibular nerves?
Difficulty with dorsiflexion and plantar flexion
Cerebral Medulla
White matter of the cerebrum
A dermatome is the area of skin supplied with sensory innervation by
a pair of spinal nerves
Exercise: For the following three sentences, determine if the condition would best be treated with a drug that is a cholinergic agonist or an antagonist.1. In Alzheimer's disease, there is a loss of cholinergic signal transmission in the brain, and patients are given a cholinergic _________.2. In myasthenia gravis, antibodies may reduce the ability of acetylcholine to bind its receptors in skeletal muscle. These patients may benefit from therapy with drugs that are cholinergic_____________.3. A farm worker severely poisoned by an insecticide that prevents acetylcholine function will benefit from receiving a cholinergic _________.
agonist, agonist, agonist
Which of these substances would most freely diffuse across the blood-brain barrier?
alcohol, levodopa, nicotine
third ventricle
center of the diencephalon
The cerebral cortex receives blood from the anterior, middle, and posterior _____ arteries.
cerebral
The basilar artery and internal carotid arteries contribute to the ring-shaped _____ ______ _____
cerebral arterial circle
Imagine a defect in arachnoid granulations, causing CSF to accumulate in the subarachnoid space (external hydrocephalus). Which of the following brain regions or structures will the surrounding CSF press up against?
cerebral cortex
In the ventricles, CSF is produced at ___________, which are composed of specialized ependymal cells surrounded by supportive connective tissue.
choroid plexuses
communication between hemispheres corpus callosum
commissural tract
Rami that carry axons associated with the sympathetic division of the ANS formed from the rami of thoracic and upper lumbar spinal nerves are called __________ rami.
communicating
The larger arteries that supply the brain with blood are located within the _______ space.
subarachnoid
Between the dura mater and the arachnoid mater lies the ____________, and between the arachnoid mater and the pia mater lies the ____________.
subdural space; subarachnoid space
A basal nucleus in the midbrain is the __________, and a basal nucleus in the diencephalon is the ___________.
substantia nigra; subthalamic
Which is not a function of the cerebrospinal fluid?
supply CNS tissues with extra protein
sensory speech area of the brain
wernicke
Lateral ventricles
within each cerebral cavity