Unit 4

Opening of voltage-gated sodium channels in the membrane of a neuron results in

depolarization

Which of the following is the most sensitive body region?

face

Temperature senses use two types of

free nerve endings

The spinal pathway(s) that carries/carry information regulating skeletal muscle tone is/are the

medial and lateral pathways

Which of the following concerning olfaction is true?

Olfactory receptors are highly modified neurons

Which statement regarding sensory reception is correct?

The CNS interprets the nature of sensory information entirely on the basis of the area of the brain stimulated.

Most postganglionic neurons of the sympathetic division are

adrenergic

Ascending pathways

carry sensory information to the brain.

The part of the CNS that adjusts voluntary and involuntary motor activities on the basis of sensory information and stored memory of previous movements is the

cerebellum

A mixed nerve

contains both sensory and motor neurons

Neurons that have two or more dendrites and a single axon extending away from the cell body are called

multipolar

Splanchnic nerves innervate

-smooth muscle in blood vessels. -the abdominopelvic organs. -walls of organs and glands in the abdomen. -the pancreas, liver, and prostate gland.

Sympathetic nerves innervate which of these structures? A)smooth muscle in the esophagus and lungs B)sweat glands in the skin of the head and neckC)smooth muscle in the blood vessels of the head, the salivary glands, and the eyeD)smooth muscle in the wall of the pancreasE)all of these9

-smooth muscle in the esophagus and lungs -sweat glands in the skin of the head and neck -smooth muscle in the blood vessels of the head, the salivary glands, and the eye -smooth muscle in the wall of the pancreas

Your young child has a middle ear infection: otitis media. There is a build-up of fluid, bacteria, and white blood cells, or pus, inside of the middle ear chamber. Why has this affected the child's hearing?

The auditory ossicles cannot vibrate freely

Changing the shape of the lens to keep the focal length constant is a process called

accommodation

Which of the following neurotransmitters usually depolarizes postsynaptic neurons?

acetylcholine

Epinephrine binds to

adrenergic receptors

The all-or-none principle states that

all stimuli great enough to bring the membrane to threshold will produce identical action potentials

Diffusion across which structure(s) returns excess CSF to venous circulation?

arachnoid granulations

During an EEG, alpha waves

are characteristic of normal resting adults

Monosynaptic reflexes

are exemplified by the stretch reflex.

Interneurons

are found only in the central nervous system

You have been diagnosed with the demyelinating disease called multiple sclerosis. The areas of damage seem to be centered within the spinal cord. The demyelinated areas are most probably within the

ascending and/or descending tracts

Regions of the brain that are involved in interpreting data or coordinating motor responses are

association areas

The largest and most numerous of the glial cells in the central nervous system are the

astrocytes

In the ANS, the preganglionic neurons synapse with postganglionic neurons in the

autonomic ganglia

Sensory receptors that respond to changes in blood pressure are called

baroreceptors

Humans are most sensitive to which taste?

bitter

Dual innervation refers to an organ receiving

both sympathetic and parasympathetic nerves

The brain and spinal cord comprise the

central nervous system

The region of the brain that is involved in conscious thought and intellectual function as well as processing somatic sensory and motor information is the

cerebrum

Neurons in the respiratory centers of the brain that respond to pH are examples of

chemoreceptors

Olfactory receptors are examples of

chemoreceptors.

All preganglionic neurons of the sympathetic and parasympathetic divisions are

cholinergic and myelinated

The effect of parasympathetic stimulation on the eye is to __________ the ciliary muscle and to __________ the pupil.

contract, constrict

The branching structures that, together with the cell body, are sensitive to chemical, mechanical, or electrical stimulation are called

dendrites

The ________ acts as a switching and relay center for integration of conscious and unconscious sensory information and motor commands.

diencephalon

Proprioceptors

do not adapt to constant stimulation

When norepinephrine binds to adrenergic receptors, the response is

either excitatory or inhibitory

Which neuroglial cells produce CSF in some regions of the brain?

ependymal cells

When norepinephrine binds to beta-adrenergic receptors on the heart, the response is

excitatory

Adrenergic synapses release the neurotransmitter

norepinephrine

The area of sensory cortex devoted to a body region is relative to the

number of sensory receptors in the region of the body

The only cranial nerve that is attached to the cerebrum is the

olfactory

The myelin sheaths that surround the axons of some of the neurons in the CNS are formed by

oligodendrocytes

Which of these characteristics describe the somatic motor nervous system?

one neuron between CNS and skeletal muscle

Temperature sensations are relayed along the same pathways that carry sensations of

pain

Parasympathetic preganglionic axons whose cell bodies are in the sacral region of the spinal cord travel through _________ nerves that innervate the urinary bladder, lower colon, etc.

pelvic

The conscious awareness of a sensation is called

perception

The movement of the stapes at the oval window establishes pressure waves in the

perilymph of the scala vestibuli

Which nerve innervates the diaphragm?

phrenic

The ________ is the layer of the meninges that is in direct contact with the surface of the brain.

pia mater

The daily day/night cycle known as a circadian rhythm involves the

pineal gland

Which of the following performs such abstract intellectual function as predicting the future consequences of events or actions?

prefrontal cortex

There are three different types of cones, each one sensitive to a different color wavelength of light. These cones are designated

red, blue, and green

The perception of pain coming from parts of the body that are not actually stimulated is called

referred pain

The frequency of a sound is indicated to the nervous system by the

region of the basilar membrane of the spiral organ that is stimulated

Which of these functions is NOT affected by parasympathetic stimulation?

secretion of sweat

Which of the following is a function of the efferent division of the nervous system?

sending signals to muscles

The effector organs for the somatic motor nervous system are

skeletal muscle

Taste receptors are

specialized epithelial cells

Collateral ganglia are associated with which of these nerves?

splanchnic nerves

Which of the following is a primary taste sensation?

sweet

Which of the following fibers usually release norepinephrine (NE)?

sympathetic postganglionic

Lamellated corpuscles (Pacinian corpuscles) are

tactile receptors

Ruffini corpuscles are examples of

tactile receptors

Gustation refers to the special sense of

taste

Which structures are related to Parkinson's disease?

the basal nuclei and the midbrain

Head injuries that damage cerebral blood vessels are serious conditions because

the blood could compress and distort the relatively soft tissues of the brain

Which of the following arrives at the primary sensory cortex?

touch sensations

Sound energy is converted into mechanical movements by the

tympanic membrane

Damage to the ________ nerve, which is vital for the autonomic control of visceral function, could result in death.

vagus

Almost 75 percent of all parasympathetic outflow travels along the

vagus nerve

Approximately 75% of all parasympathetic axons are located in the

vagus nerve (X)

The resting potential of a neuron is

-70mV

Given these characteristics: 1. sometimes called the thoracolumbar division 2. preganglionic cell bodies are located in cranial nerve nuclei or S2-S4 in the spinal cord 3. preganglionic neurons release acetylcholine 4. preganglionic neurons project to chain ganglia 5. postganglionic neurons release acetylcholine or norepinephrine Choose the characteristics that apply to the sympathetic division of the ANS.

1,3,4,5

Which of the following characteristics apply to the ANS? 1. sometimes consciously controlled 2. two neurons between the CNS and effector organs 3. all neurons myelinated 4. neurotransmitters can be acetylcholine or norepinephrine

2,4

The tympanic membrane vibrates to frequencies between

20-20,000 Hz

Identify the correct sequence of steps in the generation of an action potential. 1. Activation of sodium channels and rapid depolarization 2. Inactivation of sodium channels and activation of potassium channels 3. Depolarization to threshold 4. Closing of potassium channels

3, 1, 2, 4

Which of the following is the correct order of events that occur at a cholinergic synapse? 1. Extracellular calcium enters the axon terminal, triggering the exocytosis of acetylcholine. 2. Acetylcholine is removed by acetylcholinesterase. 3. Acetylcholine binds to receptors and depolarizes the postsynaptic membrane. 4. Axon terminal depolarizes.

4, 1, 3, 2

Given these parts of an autonomic reflex: 1. afferent neuron 2. association neuron 3. effector cell 4. efferent neuron 5. sensory receptor Choose the correct order an action potential travels through them from a stimulus to the resulting action.

5,1,2,4,3

Which of the following is abnormal in the adult?

Babinski sign

________ deafness results from conditions in the middle ear that block the normal transfer of vibrations from the tympanic membrane to the oval window.

Conduction

Which statement is true regarding action potential propagation?

In salutatory conduction, the myelin is composed of fat, which insulates the axon membrane against sodium ion flow across the membrane.

Your grandmother who lives in an assisted living facility is always complaining about how bad the food is. You eat there with her often and find the food to be cooked well and interesting, even though the food is not what you would really prefer. What is the most reasonable explanation for this?

She has fewer gustatory cells in her taste bud receptors

Motor innervation of the muscles of facial expression is transmitted through which cranial nerve?

VII

Nociceptors

have large receptive fields.

As a result of a severe concussion from a car accident, you have a terrible problem with both retaining new information and recalling old information. The injury affected the

hippocampus

You notice that your father holds his book farther from his face than he used to. Since you are taking an anatomy and physiology course, you realize that this is due to

his lens being unable to accommodate for close objects

A stimulus that opens gated potassium ion channels, moving the membrane voltage value below the resting potential value, results in which of the following?

hyperpolarization

Which of these effects results from the stimulation of the parasympathetic division?

increased contraction of smooth muscle in the wall of the digestive tract

Saltatory conduction

is faster than conduction on an unmyelinated axon

Another name for the patellar reflex is the

knee-jerk reflex

Cell bodies of the sympathetic preganglionic neurons are located in the

lateral horn of the spinal cord gray matter

The ________ establishes emotional states.

limbic system

A major center concerned with autonomic function, such as heart rate, blood pressure, and respiration is the

medulla oblongata

Small phagocytic glial cells, which are derived from white blood cells, are called

microglia

Receptors in the ________ provide sensations of gravity and linear acceleration.

vestibule

Most neurons lack centrioles. This observation explains

why such neurons cannot divide through mitosis.

Pulling away from a painful stimulus is an example of a(n) ________ reflex.

withdrawal