Chapter 13

Question 1

blood vessels contract

Answer 1

, keeping the sweat glands closed (conserving heat),

Question 2

the endocrine system

Answer 2

delivers chemical messages to your body and determines the rate of reactions. The endocrine system coordinates with the nervous system to ensure that processes are happening at a homeostatic speed.

Question 3

Parathyroid Hormone (PTH)

Answer 3

A hormone secreted by the parathyroid that helps raise blood calcium concentrations.

Question 4

Calcitriol

Answer 4

A hormone that is a form of vitamin D that aids in calcium absorption.

Question 5

Calcitonin

Answer 5

A hormone secreted by the thyroid gland that helps lower blood calcium concentrations.

Question 6

Aldosterone

Answer 6

A hormone that facilitates sodium reabsorption and potassium and hydrogen excretion.

Question 7

Hypercalcemia

Answer 7

An excess of calcium in the blood. Heightened nervous and muscle excitability

Question 8

Hypocalcemia

Answer 8

A deficiency of calcium in the blood. Nerves and muscle are less responsive to messages.

Question 9

Perception

Answer 9

is the conscious awareness of stimuli received by sensory receptors.

Question 10

Sensation

Answer 10

requires a stimulus, a sensory receptor, and conduction of an action potential to the CNS.

Question 11

The somatic senses

Answer 11

include touch, pressure, temperature, proprioception, and pain.

Question 12

The visceral senses

Answer 12

are primarily pain and pressure.

Question 13

The special senses

Answer 13

are smell, taste, vision, hearing, and balance.

Question 14

Primary receptors

Answer 14

have axons that transmit action potentials toward the CNS.

Question 15

Secondary receptors

Answer 15

have no axons but release neurotransmitters.

Question 16

Adaptation .

Answer 16

is decreased sensitivity to a continued stimulus.

Question 17

Tonic receptors

Answer 17

adapt slowly;

Question 18

phasic receptors

Answer 18

adapt rapidly

Question 19

The spinothalamic tract - anterolateral

Answer 19

carries pain, temperature, light touch, pressure, tickle, and itch sensations.

Question 20

The two major ascending systems

Answer 20

are the anterolateral and the dorsal-column/medial-lemniscal systems.

Question 21

The ascending neurons of the spinoreticular tract - anterolateral

Answer 21

ascend both contralaterally and ipsilaterally, project to the reticular formation, and influence the level of consciousness.

Question 22

The ascending neurons of the spinomesencephalic tract - anterolateral

Answer 22

carry action potentials from cutaneous pain receptors. The spinomesencephalic tract also contributes to eye reflexes.

Question 23

The dorsal-column/medial-lemniscal system

Answer 23

carries the sensations of two-point discrimination, proprioception, pressure, and vibration.

Question 24

The trigeminothalamic tract

Answer 24

carries sensory information from the face, nose, and mouth.

Question 25

The spinocerebellar tracts

Answer 25

carry unconscious proprioception to the cerebellum from the same side of the body.

Question 26

The direct motor pathways

Answer 26

maintain muscle tone and control fine, skilled movements in the face and distal limbs.

Question 27

The indirect motor pathways

Answer 27

control conscious and unconscious muscle movements in the trunk and proximal limbs.

Question 28

The speech area

Answer 28

is in the left cerebral cortex in most people.

Question 29

The Wernicke area

Answer 29

comprehends and formulates speech.

Question 30

The Broca area

Answer 30

receives input from the Wernicke area and sends impulses to the premotor and motor areas, which cause the muscle movements required for speech.

Question 31

The right and left hemispheres

Answer 31

are connected by commissures. The largest commissure is the corpus callosum, which allows the sharing of information between hemispheres.

Question 32

Short-term memory

Answer 32

requires long-term potentiation. The two types of memory are declarative and procedural.

Question 33

Long-term memory

Answer 33

is converted from short-term by consolidation. The two types of memory are declarative and procedural.

Question 34

The limbic system

Answer 34

is involved with emotions, motivation, mood, visceral functions, and memory. Olfactory stimulation is a major influence.

Question 35

Free nerve endings

Answer 35

detect light touch, pain, itch, tickle, and temperature.

Question 36

Merkel disks

Answer 36

respond to light touch and superficial pressure.

Question 37

Hair follicle receptors

Answer 37

wrap around the hair follicle and are involved in the sensation of light touch when the hair is bent.

Question 38

Pacinian corpuscles

Answer 38

, located in the subcutaneous tissue, detect pressure. In joints, they serve a proprioceptive function.

Question 39

Meissner corpuscles

Answer 39

, located in the dermis, are responsible for two-point discriminative touch.

Question 40

Golgi tendon organs

Answer 40

embedded in tendons, respond to changes in tension.

Question 41

Ruffini end organs

Answer 41

are involved in continuous touch or pressure.

Question 42

Muscle spindles

Answer 42

, located in skeletal muscle, are proprioceptors.