A&P Exam 1 - izzy

What is detected by the hair cells in the semicircular canals?

Direction of motion

When the flexor muscles of one arm contract in a withdrawal reflex, the extensor muscles of the other arm contract. What is this response called?

Crossed extensor reflex

What condition is due to an abnormality in the curvature of the lens or cornea, resulting in some areas of blurry vision?

Astigmatism

Where are axons of somatic motor neurons located?

Anterior root

Olfactory receptors are examples of what class of sensory receptors?

Chemoreceptors

If a resting potential becomes negative, the membrane is said to be _______.

Hyperpolarized

What is the cauda equina?

A bundle of nervous tissue that extends beyond the tip of the spinal cord

With a subdural hematoma resulting from a blow to the head, where has the blood accumulated?

Between the dura mater and the arachnoid mater

The following are the main steps in the generation of an action potential

a. Sodium channels are inactivated

b. Voltage-gated potassium channels open and potassium moves out of the cell, initiating repolarization

c. Sodium channels regain their normal properties

d. A graded depolarization brings an area of an excitable membrane to the threshold

e. A temporary hyperpolarization occurs

f. Sodium channel activation occurs

g. Sodium ions enter the cell and depolarization occurs

The proper sequence of these events is:

D, F, G, A, B, C, E

Which cells produce myelin in the brain and spinal cord?

Oligodendrocytes

A patient awakes in the morning unable to move their right arm and has trouble speaking. The paramedics believe the patient is having a stroke. What lobes of the cerebrum are most likely affected by the stroke?

Left frontal lobe

What gives rise to the color of the white matter in the brain?

Myelinated axon

Cerebrospinal fluid reenters the blood via ______.

Arachnoid granulations

The resting cell membrane is more permeable to which ion?

Potassium

What neurotransmitter is not secreted in sufficient quantity by neurons in the basal nuclei, leading to the development of Parkinson's disease?

Dopamine

What comprises the central nervous system (CNS)?

Brain and spinal cord

What is connected to the hypothalamus via the infundibulum?

Pituitary gland

What might result from injury to the reticular formation?

Unconsciousness or coma

During exercise, what part of the nervous system inhibits digestion and increases heart rate?

Sympathetic Nervous System

Which of these fiber types are typically adrenergic?

Sympathetic postganglionic fibers

Following a brain injury, a soldier is now unable to speak. What area of the brain was most likely damaged?

Broca's area

Which lobe of your brain are you using when you answer this question?

Frontal lobe

After taking a bite of pizza, sensory receptors are stimulated in your mouth. What is the order of information flow that results?

Stimulation of sensory receptors → impulse sent to CNS → sensation → perception

Which neurotransmitters are modified amino acids?

Dopamine, Serotonin, and Epinephrine

If a neuron is stimulated causing changes in the membrane potential to the point where voltage-gated Na+ channels open and begin depolarizing the cell, the neuron is said to have reached ______.

Threshold

An accident involving blunt-force trauma to the head may result in loss of vision. For this symptom to occur, what area of the brain might be damaged?

Occipital lobe

What disorder involves an immune response that affects the myelin coating on axons throughout the spinal cord and brain, triggering inflammation and leaving scars?

Multiple sclerosis

What condition can be treated with a cochlear implant?

Sensorineural deafness

A physiologist testing signal transduction rates in two different nerve fibers notices that one fiber conducts signals much faster than the other. What is the most likely difference between the two?

The faster nerve fiber is myelinated and the slower one is not

What change results in farsightedness after the age of forty-five?

Loss of lens elasticity

In Guillain-Barre syndrome, the immune system attacks and degrades the myelin sheath of PNS axons. Predict the effect this will have on nerve impulses and motor function.

Lost insulation from myelin will cause neurons of the PNS to lose saltatory conduction, resulting in poor muscle function

What cranial nerves are comprised of only sensory fibers?

Olfactory nerves (CN I), optic nerves (CN II), and vestibulocochlear nerves (CN VIII)

What is the correct order for the components of a reflex arc?

Receptor, sensory neuron, interneuron, motor neuron, effector

What is the term given to pain that feels like it is coming from an area of the body other than the area being stimulated?

Referred pain

Impulses conducted along the corticospinal tracts are _______ in nature and control ______.

motor; voluntary muscle movements

When does the refraction of light occur?

When light passes at an angle from one medium to another with a different density

Synaptic knobs are at the ends of ______.

Axons

What is contained in the dorsal root ganglia?

Cell bodies of sensory neurons

What region of the retina provides the sharpest vision?

Fovea centralis

Hair cells of the spiral organ are located on the ______ and depolarize in response to sound.

Basilar membrane

What is the function of sensory receptors?

To detect changes in and outside the body

Which cranial nerves are primarily motor nerves innervating the muscles that move the eyes?

Oculomotor nerves (CN III), trochlear nerves (CN IV), and abducens nerves (VI)

What functional area is located in the postcentral gyrus?

Somatosensory cortex

What is the function of the basal nuclei?

Facilitate and help coordinate voluntary movement

Organize the following list of functions and actions according to the branch of the nervous system that controls each one.

Heart rate

Walking

Looking to the left

Digestion

Vasoconstriction

Picking up a glass

Somatic: walking, looking to the left, picking up a glass

Autonomic: heart rate, digestion, vasoconstriction

Muscle spindles and Golgi tendon organs are receptors for _____.

Proprioception

Where is the primary motor area of the brain located?

The precentral gyrus of the frontal lobe

What is the destination of fibers of the spinothalamic tract transmitting pain and temperature information?

Thalamus

Where did the sensory fibers originate that cross in the optic chiasma?

The medial (nasal) side of each retina

Description of a receptor potential.

Local graded potential that reflects the strength of the stimulus

What part of the nervous system prepares the body for stressful or emergency situations?

Sympathetic nervous system

What type of structures are temperature receptors?

Free nerve endings

The auditory tube runs between the throat and the _______.

Middle ear

What is a dermatome?

Region of skin innervated by a single spinal nerve

What occurs during reuptake?

A neurotransmitter that has already been released into the synaptic cleft is taken back into the presynaptic neuron