exam 5

Drug Y inhibits the activity of parasympathetic information. Which cranial nerve would possibly be affected?

All the answer choices are correct

Tabitha's symptoms indicate a problem with her nervous system. If the myelin on Tabitha's neurons is damaged, which of the following would happen?

An action potential may not make it to the axon terminal.

Which structure is not correctly paired with its structure & function?

Basal nuclei: regulates movements and found in the posterior (dorsal) root that extends from the spinal cord

When a pathologist performs an autopsy on a person who died of brain injury, why would he/she find large numbers of microglia?

Brain injury leads to extensive debris in the area. Microglia mitotically divided into large numbers right before death and aggregated to clean up the damaged area.

How do painkillers relieve pain?

By blocking the transmission and perception of the pain stimuli in the brainstem

Damage to what region of the spinal cord could have the patient potentially unable to breathe unassisted?

C3

Which of these ions triggers exocytosis of synaptic vesicles

Ca2+

Ms. Karabekian suffers a vertebral fracture that damages many ganglia, then loses feeling in much of her leg. What is likely to occur?

Chance of recovery of the damaged neurons is minimal.

Which of these does not directly describe the autonomic nervous system?

Composed of sensory neurons

All cranial nerves are considered mixed nerves.

False

The posterior (dorsal) root of a spinal nerve and the posterior ramus are considered mixed nerves since they both carry sensory and motor information.

False

The simple stretch reflex employs mechanoreceptors known as Golgi tendon organs to detect the degree of stretch experienced by a muscle.

False

The trigeminal nerve (V) has three nerve branches: optic nerve, maxillary nerve, and oculomotor nerve.

False

Which of the following is mismatched when the nerve is damaged?

Femoral nerve-knee pain

The primary somatosensory cortex interprets incoming somatic sensory information such as touch or temperature. Different areas of the body have a higher density of sensory receptors and in turn a higher proportion of the primary somatosensory cortex dedicated to it. Which body region would you expect to have the highest density of sensory receptors?

Fingertips

The basal nuclei are a collection of cell bodies that modify the activity of upper motor neurons to produce voluntary movements. Damage to any factor of this system results in a movement disorder. Damage to any of the following will cause difficulty in initiating movement except the:

Globus pallidus

Drug X stimulates parasympathetic nervous system that often leads to adverse effects of excessive drooling. Which nerve is affected?

Glossopharyngeal nerve

Tabitha has ingested a large quantity of lead, which has interfered with the normal functions of the neurotransmitters in her brain. Which of the following neurotransmitters is incorrectly matched with its predominant function?

Glutamate is the most important inhibitory neurotransmitter in the central nervous system

Which of the following characteristics regarding peripheral nerves is false?

If there is damage to a nerve, there is a higher probability of sensory information being impaired.

During an action potential, hyperpolarization is caused by:

K+ efflux

Uncle Mel suffers from depression and is having trouble sleeping. Some medications can increase the amount of neurotransmitter in the synapse by preventing its re-uptake into the presynaptic neuron or its degradation. This increases the level of the neurotransmitter in the synapse and prolongs its effects. Select which neurotransmitters you think might be a good target for anti-depressant drugs.

Norepinephrine,DopamineSerotonin

The burning sensation in Tabitha's feet is carried into the CNS by small, unmyelinated axons. Which of the following is NOT occurring in those axons?

Only the voltage-gated sodium ion channels found in the gaps or nodes of Ranvier are activated.

Which of the following types of cells are responsible for sensing touch, stretch, joint position, pain, and temperature?

Pseudounipolar neurons

A physician's assistant named Jose begins to examine Tabitha by testing her reflexes. Which statement best describes the path of information as it travels through the nervous system?

Sensory information is collected by sensory receptors in the PNS. Input travels to the CNS, where it is integrated and a response is put into action by effectors, usually muscles or glands.

Predict the effects of damage to the lower motor neuron.

Skeletal muscle atrophy may occur.

Damage to which division of the peripheral nervous system (PNS) would be life-threatening?

Somatosensory division

Injuries may damage the nerves of any motor or sensory division of the PNS. In which PNS subdivision would a nerve injury be the most threatening to survival?

Sympathetic nervous system

A patient involved in a car accident was transported to the hospital for a severe head injury. Upon her arrival, the doctor has given her a poor chance of survival due to the injuries she sustained. Based on his diagnosis, which part of the brain was damaged?

The brainstem

Why do individuals who suffer from brainstem injuries have difficulty with their autonomic functions?

The brainstem contains the autonomic centers and the cell bodies of many parasympathetic neurons that regulate autonomic responses.

Why is a patient in a vegetative state, expressing no cortical activity, able to survive for a period of time?

The brainstem controls basic life functions.

Where is a postganglionic cell located?

The cell body is located in the ganglion; the axon comes after the ganglion.

Mr. Pratchett has damage to his facial nerve, but not his trigeminal nerve. What would happen to his corneal blink reflex?

The cornea will send somatosensory information via the trigeminal nerve to the pons, but due to facial nerve damage, it will not be able to induce the orbicularis oculi muscle to contract.

Tetrodotoxin is a toxin that blocks voltage-gated sodium ion channels. What effect would this have on the function of neurons?

The neuron would be unable to generate action potentials.

Heavy metals can block calcium channels in neurons. Predict what would happen to Tabitha's neurons.

The pre-synaptic neurons would be unable to release neurotransmitter.

Cocaine blocks the reuptake of dopamine, causing a high level of dopamine that stimulates the postsynaptic receptors for an extended period. Why would people who abuse cocaine eventually need more of the drug to reach an equivalent "high"?

The receptors will be downregulated (decreased). This will lead to desensitization of dopamine response

Action potentials (nerve impulses) are changes in the membrane potential that, once started, will affect the entire excitable membrane. The first action potential is usually generated at the initial segment of the neuron's axon. This activity will test your understanding of the sequence of events that occur at the membrane of the initial segment of the axon during generation of an action potential.

Threshold stimulus Na+ channels open Na+ influx Depolarization Na+ channels close K+ channels open K+ efflux Repolarization Hyperpolarization K+ channels close

The nerve roots that fuse to form the spinal nerves serving the upper and lower limbs are attached to the spinal cord at the cervical and lumbar enlargements of the spinal cord.

True

The reticular formation can exercise control over autonomic centers if its connection with the hypothalamus is severed.

True

Which of the following is not a result of the activation of the sympathetic nervous system?

Vasodilation to the digestive organs

What type of motor neuron stimulates skeletal muscle fibers to contract by the excitation-contraction mechanism?

What type of motor neuron stimulates skeletal muscle fibers to contract by the excitation-contraction mechanism?

Which of the following neurotransmitters is responsible for stimulation of skeletal muscle and in the ANS?

acetylcholine

Chronic alcohol abuse will not only cause an individual to develop liver damage, but may also lead to cerebellar damage. Damage to the cerebellum will cause the individual to:

appear clumsy and uncoordinated

Nicotine is a drug that stimulates nicotinic receptors. It will have an effect __________.

at all autonomic ganglia

During an action potential, when does sodium ion permeability begin to significantly decline?

at the peak of depolarization

A patient expresses feeling dizzy when standing, nauseated when eating, and having difficulty with emptying their bladder. You want to run some tests to determine if they are suffering from:

autonomic neuropathy.

Unlike autonomic motor neurons, somatic motor neurons __________.

can only stimulate their target cells and not inhibit them

As you sit down to take your final anatomy and physiology exam you begin to feel your heart rate and breathing increase. You realize that the parts of the brain causing these affects are the:

cerebral cortex, hypothalamus, and reticular formation

A young boy, who is normally gentle and kind, is showing signs of aggression and anger after falling off the monkey bars on the playground and hitting his head hard on the ground. After examination, the doctor determines he has damaged part of his:

cerebrum

Action potential propagation in unmyelinated axons happens via:

continuous conduction

Depolarization to threshold during action potential propagation in axons is due to:

diffusion of Na ions down to the next segment of the axon

Your doctor is discussing the side effects of an upcoming surgery to remove your left and right amygdala. He says that the effects can vary, but you should expect:

emotional abnormalities

The preganglionic and postganglionic fibers of the parasympathetic divisions secrete the neurotransmitter ACh. Drugs that stimulate ACh release will:

enhance the effects of the parasympathetic division, such as excessive drooling, diarrhea, and poor distance vision.

Which of the following cells secretes CSF into the ventricles of the brain?

ependymal cells

Which of the following is a function of astrocytes?

facilitate the formation of the blood-brain barrier

A typical somatic sensory neuron is classified as a:

first-order neuron.

Which of the following structures house the axons of sympathetic postganglionic neurons?

gray rami communicantes

The relative refractory period is caused by:

hyperpolarization

A series of measurements with a voltmeter show a neuron's membrane potential becoming more negative, from -70 mV to -85 mV. This neuron is experiencing a:

hyperpolarization phase.

Batrachotoxin produced by certain species of frogs is a toxin that permanently opens voltage-gated Na ion channels. The results of exposure to batrachotoxin will be:

inability to generate action potentials

Nicotine is addictive because it causes dopamine-releasing neurons to fire more action potentials. Nicotine will therefore cause:

increased levels of dopamine in the synaptic cleft

If a medication were able to selectively block nicotinic receptors on sympathetic postganglionic neurons, it would:

inhibit stimulation of sympathetic postganglionic receptors.

Conduction speed will be fastest in a __________.

large myelinated axon

Preganglionic neurons of the sympathetic nervous system originate in the:

lateral horns of the spinal cord.

A patient enters the ER with loss of muscle function on the right side of her body. The initial exam indicates she may have suffered a stroke in her:

left cerebral hemisphere

Where is the motor response initiated?

motor areas of the brain

The major neurotransmitter at sympathetic target organs is __________.

norepinephrine

Compared to chemical synapses, electrical synapses:

offer faster cell-cell communication

Which of the following neurotransmitters is important for arousal from sleep?

orexin

A resting neuron is an unstimulated neuron that is not presently generating an action potential. The resting membrane potential is the separation of the relative positive and negative charges across the membrane of a cell at rest.

out side (+) Inside (-)

Which of the following innervates target cells or organs of the autonomic nervous system (ANS)?

postganglionic neuron

Which muscle or muscle group is served by the femoral nerve?

quadriceps femoris group

Sensory receptors that adapt to stimuli after a certain period of time are:

rapidly adapting receptors.

A neurological condition, lissencephaly, results in a lack of gyri and sulci, leaving the brain surface almost completely smooth. The effect of this on the cortex leads to:

reduced surface area and fewer neurons.

Autonomic centers are located in the __________.

reticular formation

You've looked for your keys for the past ten minutes in several different places. The ability to keep track of the places you've already looked is stored in:

short-term (working) memory.

The axons of parasympathetic postganglionic neurons are:

short.

Upon entering your house, you noticed the smell of cake baking in the oven. What division of the peripheral nervous system is responsible?

somatic sensory division

Sensory information from proprioceptors about joint and muscle positions are carried to the brain by the:

spinocerebellar tracts.

Gene's parachute did not open when he jumped out of the airplane. He injured his back in the thoracic and lumbar regions, damaging the autonomic ganglia found close to his spinal cord. What neurons did he likely damage?

sympathetic preganglionic neurons

An accident destroyed the sympathetic ganglion housing the neurons that innervate David's heart. However, during exercise, his heart rate and blood pressure increase normally. This occurs because:

the adrenal medulla remains undamaged and can secrete epinephrine and norepinephrine into the bloodstream to stimulate the heart

If a drug inhibits neurotransmitter receptors on the postsynaptic cells:

the neurotransmitter will have no effect in the postsynaptic cell

During an action potential, the rapid decrease in sodium ion permeability and the simultaneous and rapid increase in potassium ion permeability is responsible for __________.

the repolarization phase

Which of the following is an essential characteristic of the blood brain barrier?

tight junctions between endothelial capillary cells

The channels that open when the axolemma reaches threshold depolarization are the:

voltage-gated Na ion channels

The generation of an action potential in a neuron requires the presence what type of membrane channels?

voltage-gated channels