Mastering A &P Chapter 13

Which of the receptor types shown here functions exclusively as a proprioceptor?

(B) Proprioceptors are sensitive to stimuli associated with body movements. The muscle spindle shown in B is responsive to muscle stretch.

Which of the receptor types might function as a nociceptor?

(a) Nociceptors respond to potentially damaging stimuli like noxious chemicals and extremes of temperature or pH. Nociceptors are generally associated with free nerve endings of specialized neurons.

You are removing a hot pan of cookies from the oven, using a pot holder. Suddenly, you feel a surge of heat through the pot holder. Why don't you react by dropping the baking pan and spilling cookies all over the floor?

Cortical integration centers override the spinal reflex.

What is a benefit of a nerve plexus?

Damage to one single branch of a plexus does not necessarily disrupt all motor information sent to a region. Because individual spinal nerves fuse and mix their flow through branches in the plexus, no one damaged area blocks nervous flow completely.

Reciprocal inhibition means that while one sensory nerve is stimulated, another sensory neuron for synergistic muscles in the same area is inhibited and cannot respond.

False

Which of the following is NOT correct concerning nerves? Nerves are analogous to tracts in the CNS. Nerves are collection of axons of either sensory or motor neurons but not both. Nerves are covered by an outer sheath called the epineurium. Nerves do not contain cell bodies.

Nerves are collection of axons of either sensory or motor neurons but not both.

A patient is suffering from the inability to distinguish various types of odors. This patient may have damage to which of the following?

Olfactory Nerve (I)

In order for you to realize there has been a sensory change, it has to reach the __________ level of processing.

Perceptual The perceptual level is the third (final) level of neural integration in the somatosensory system. This is when you become aware of a stimulus.

All processing at the circuit level going up to the perceptual level must synapse in the ________.

Thalamus

Which cranial nerve innervates most of the visceral organs?

Vagus

If the ventral root of a spinal nerve were cut, what would be the result in the tissue or region that nerve supplies?

a complete loss of voluntary movement

Which of the following cranial nerves carries only motor information?

abducens The abducens carries efferent (motor) signals to the extrinsic eye muscle that abducts the eye (turns it laterally).

Nerves that carry impulses toward the CNS only are ________.

afferent nerves

Which reflex is triggered when a stranger suddenly grasps your arm?

crossed-extensor reflex The grasped arm is withdrawn (via the flexor reflex) as the opposite arm pushes you away from the attacker (via crossed-extensor reflex). As in this scenario, the crossed-extensor reflex often accompanies the flexor reflex.

Which connective tissue layer directly surrounds individual axons in a nerve?

endoneurium

Which of the following is NOT required for a reflex arc? interneurons receptors motor neurons sensory neurons

interneurons are the integration point for reflexes, but they are not necessary

Which type of sensory receptor allows us to feel an insect landing on our skin?

mechanoreceptors

If someone spills very hot coffee (200°F) on their skin, they will likely perceive much pain. Which of the following receptor types is causing this sensation?

nociceptors

The letter E would represent which of the following muscles during the knee-jerk reflex?

rectus femoris The rectus femoris is one of the quadriceps. Stimulation of muscle spindles by tapping of the patellar ligament results in the reflex contraction of these muscles and the extension of the knee.

The knee-jerk reflex is an example of a __________.

stretch reflex

A reflex that causes muscle relaxation and lengthening in response to muscle tension is called a ________.

tendon reflex

What reaction would occur if the muscle labeled E were suddenly pulled longer?

the contraction of muscle E A sudden stretch in a muscle leads to the contraction of the stretched muscle (E) and the relaxation of the antagonistic muscle (G).

A patient has an injury of the spine and is now suffering from a loss of motor function in his right arm. However, he still has normal sensory function in the arm. Based on this information it is likely that the patient has nervous tissue damage located at ________.

the ventral root located at one or more of the cervical vertebra

Striking the "funny bone" is actually stimulation of (or injury to) the ________.

ulnar nerve