Ther Ex 5

Question 1

the body’s means of perceiving and responding to events in the internal and external environments. Receptors capable of sensing touch, pain, temperature, and chemical stimuli send information to the CNS concerning changes in our environment. The CNS responds by either voluntary movement or a change in the rate of release of specific hormones from the endocrine system, depending on which response is appropriate.

Answer 1

Nervous system

Question 2

Nervous system is divided into 2 divisions

Answer 2

Central nervous system and peripheral nervous system

Question 3

PNS is divided into

Answer 3

Afferent (go towards) and efferent (go away)

Question 4

Nerve cells are divided into

Answer 4

Cell body, axon, and dendrites

Question 5

Axons are covered by

Answer 5

Schwann cells

Question 6

At rest, neurons are negatively charged in the interior with respect to the electrical charge outside the cell. This difference in electrical charge is

Answer 6

Resting potential

Question 7

When the depolarization reaches threshold, an

Answer 7

action potential or nerve impulse is initiated

Question 8

Neurons communicate with other neurons at junctions called

Answer 8

Synapses

Question 9

Neurotransmitters can be

Answer 9

Excitatory or inhibitory

Question 10

increases neuronal permeability to sodium and results

Answer 10

excitatory transmitter i

Question 11

cause the neuron to become more negative (hyperpolarized). This hyperpolarization of the membrane

Answer 11

Inhibitory neurotransmitters

Question 12

position receptors located in joint capsules, ligaments, and muscles.

Answer 12

Proprioceptors

Question 13

The three most abundant joint and ligament receptors are

Answer 13

nerve endings, Golgi­type receptors, and Pacinian corpuscles

Question 14

The muscle spindle functions as a

Answer 14

Length detector

Question 15

continuously monitor the tension developed during muscular contraction.

Answer 15

Golgi tendon organs

Question 16

In essence, Golgi tendon organs serve as safety devices that help prevent

Answer 16

Excessive force during muscle contractions

Question 17

proprioceptors provide important information to the CNS about

Answer 17

body position and speed of limb movement, which is essential for the successful performance of complex sports skills.

Question 18

are sensitive to chemical changes around muscle fibers.

Answer 18

Muscle chemoreceptors

Question 19

When stimulated, muscle chemoreceptors send information back to the CNS about the

Answer 19

metabolic rate of muscular activity, and these messages play a role in the regulation of both the cardiovascular and pulmonary response to exercise

Question 20

The somatic motor portion of the peripheral nervous system is responsible for

Answer 20

carrying neural messages from the spinal cord to skeletal muscle fibers.

Question 21

A motor neuron and all the muscle fibers that it innervates are known as

Answer 21

Motor unit

Question 22

The number of muscle fibers innervated by a single motor neuron is called the

Answer 22

Innervation ratio

Question 23

the progressive recruitment of motor units, beginning with the smallest motor neurons and progressing to larger and larger motor neurons.

Answer 23

The size principle

Question 24

Recruiting smaller motor neurons that innervate slow (highly oxidative) muscle fibers first helps to

Answer 24

delay muscle fatigue when high force production is not required to perform the exercise.

Question 25

The vestibular apparatus is responsible for maintaining

Answer 25

general equilibrium and is located in the inner ear. Specifically, these receptors provide information about linear and angular acceleration.

Question 26

The brain can be subdivided into three parts:

Answer 26

Cerebrum, cerebellum, and brain stem

Question 27

The motor cortex controls motor activity with the aid of

Answer 27

input from subcortical areas.

Question 28

Sports with a high risk of traumatic brain injury (i.e., concussions) include

Answer 28

American football, gymnastics, ice hockey, and boxing

Question 29

Repeated sports­related brain injuries are associated with

Answer 29

h a higher risk of neurodegenerative diseases (e.g., dementia

Question 30

The disease process responsible for traumatic brain injury–induced dementia is called

Answer 30

chronic traumatic encephalopathy (CTE).

Question 31

Evidence exists that the spinal cord plays an important role in

Answer 31

voluntary movement, with groups of neurons controlling certain aspects of motor activity.

Question 32

The spinal mechanism by which a voluntary movement is translated into appropriate muscle action is

Answer 32

Spinal tunning

Question 33

Reflexes provide the body with a rapid, unconscious means of reacting to a

Answer 33

Painful stimuli

Question 34

Control of voluntary movement is complex and requires the

Answer 34

cooperation of many areas of the brain as well as several subcortical areas

Question 35

The first step in performing a voluntary movement occurs in

Answer 35

subcortical and cortical motivational areas, which send signals to the association cortex, which forms a “rough draft” of the planned movement.

Question 36

The movement plan is then sent to both the

Answer 36

Cerebellum and basal nuclei

Question 37

Cerebellum responsible for making

Answer 37

FAST movements

Question 38

Basal nuclei responsible for

Answer 38

slow or deliberate movements

Question 39

the precise program is sent through the thalamus to the motor cortex, which forwards the message down to spinal neurons for “spinal tuning” and finally to skeletal muscle.

Question 40

Feedback to the CNS from muscle receptors and proprioceptors allows for the

Answer 40

modification of motor programs

Question 41

Motor unit aging becomes prominent in most individuals after the age

Answer 41

of 60, and accelerates after 75 to 80 years.

Question 42

Motor unit aging translates to declines in

Answer 42

reflex response times, peak power, and peak force generation. Lifelong exercise training is a potent preventative measure for limiting age­related declines in neuromuscular function

Question 43

The autonomic nervous system is responsible for maintaining the constancy

Answer 43

the body’s internal environment.

Question 44

the autonomic nervous system can be divided into two divisions

Answer 44

(1) the sympathetic division and (2) the parasympathetic division.

Question 45

the sympathetic portion

Answer 45

(releasing norepinephrine) tends to excite an organ

Question 46

The parasympathetic portion (releasing acetylcholine) tends to

Answer 46

Inhibit same organ

Question 47

The human body contains more than 600 voluntary skeletal muscles, which constitute 40% to 50% of the total body weight. Skeletal muscle performs three major functions:

Answer 47

(1) force production for locomotion and breathing, (2) force production for postural support, and (3) heat production during cold stress.

Question 48

Individual muscle fibers are composed of hundreds of threadlike protein filaments called

Answer 48

myofibrils

Question 49

The region of sarcoplasm surrounding an individual nucleus is termed the

Answer 49

Myonuclear domain

Question 50

Motor neurons extend outward from the spinal cord and innervate

Answer 50

Individual muscle fibers

Question 51

Muscle fatigue is defined as a

Answer 51

reduction in muscle power output that results from decreased muscle force generation and/or decreased shortening velocity.

Question 52

Muscle cramps are

Answer 52

spasmodic and involuntary muscle contractions.

Question 53

Although the exact cause of muscle cramps remains unsettled, it appears that motor neuron hyperexcitability is likely the general underlying cause of many exercise­induced muscle cramps suggesting that muscle cramps originate from the

Answer 53

central nervous system.

Question 54

Successful power athletes (e.g., sprinters) generally possess a large percentage of

Answer 54

Fast muscle fibers and therefore a low percentage of slow, type I fibers.

Question 55

The amount of force generated during muscular contraction is dependent on the following factors:

Answer 55

(1) types and number of motor units recruited, (2) the initial muscle length, (3) the nature of the motor units’ neural stimulation, and (4) prior contractile activity of the mu

Question 56

The addition of muscle twitches is termed

Answer 56

Summation

Question 57

When the frequency of neural stimulation to a motor unit is increased, individual contractions are fused in a sustained contraction called

Answer 57

Tetanus

Question 58

The peak force generated by muscle decreases as the speed of movement

Answer 58

Increases

Question 59

release hormones directly into the blood to alter the activity of tissues possessing hormone­specific receptors

Answer 59

Endocrine glands

Question 60

The free plasma hormone concentration determines the

Answer 60

magnitude of the effect at the tissue level.

Question 61

The free hormone concentration can be changed by altering the rate of

Answer 61

secretion or inactivation of the hormone, the quantity of transport protein, and the plasma volume.

Question 62

The hormone—receptor interaction triggers events at the

Answer 62

Cell

Question 63

Changes in the concentration of the hormone, the number of receptors on or in the cell, and hormone—receptor affinity all influence

Answer 63

magnitude of the effect

Question 64

Thyroid hormones T3 and T4 are important for maintaining the

Answer 64

metabolic rate and allowing other hormones

Question 65

The adrenal medulla secretes the

Answer 65

catecholamines epinephrine (E) and norepinephrine (NE)

Question 66

secreted from the adrenergic neurons of the sympathetic nervous system.

Answer 66

norepinephrine (NE).

Question 67

The adrenal cortex secretes

Answer 67

s aldosterone (mineralocorticoid), cortisol (glucocorticoid), and estrogens and androgens

Question 68

regulates Na+ and K+ balance

Answer 68

Aldosterone

Question 69

increases with strenuous exercise

Answer 69

Aldosterone secretion

Question 70

is secreted by the β cells of the islets of Langerhans in the pancreas and promotes the storage of glucose

Answer 70

Insulin

Question 71

The hypothalamus controls the activity of both the

Answer 71

Anterior pituitary and posterior pituitary

Question 72

GH is released from the anterior pituitary gland and is essential for

Answer 72

Normal growth

Question 73

GH increases during exercise to

Answer 73

mobilize fatty acids from adipose tissue and to aid in the maintenance of blood glucose

Question 74

Chronic exercise (training) can decrease

Answer 74

testosterone levels in males and estrogen levels in females. The latter adaptation has potentially negative consequences related to osteoporosis.

Question 75

The latter mechanism is enhanced during exercise due to the increase

Answer 75

In calcium

Question 76

act in a permissive manner to support the actions of other hormones during exercise

Answer 76

hormones thyroxine, cortisol, and growth hormone

Question 77

Growth hormone and cortisol also provide a

Answer 77

“slow­acting” effect on carbohydrate and fat metabolism during exercise

Question 78

Plasma glucose is maintained during exercise by increasing

Answer 78

liver glucose mobilization, using more plasma FFA, increasing gluconeogenesis, and decreasing glucose uptake by tissues. The decrease in plasma insulin and the increase in plasma E, NE, GH, glucagon, and cortisol during exercise control these mechanisms to maintain the glucose concentration

Question 79

Glucose is taken up 7 to 20 times faster during

Answer 79

exercise than at rest—even with the decrease in plasma insulin. The increases in intracellular Ca++ and other factors are associated with an increase in the number of glucose transporters that increase the membrane transport

Question 80

Training causes a reduction in circulating levels of

Answer 80

E, NE, glucagon, and insulin responses to exercise.

Question 81

The plasma FFA concentration decreases during

Answer 81

heavy exercise even though the adipose cell is stimulated by a variety of hormones to increase triglyceride breakdown to FFA and glycerol

Question 82

A healthy immune system requires the teamwork of two layers of immune protection:

Answer 82

(1) innate immune system and (2) acquired immune system.

Question 83

protects against foreign invaders and is composed of three major components: (1) physical barriers such as the skin and the mucous membranes that line our respiratory, digestive, and genitourinary tracts; (2) specialized cells (e.g., phagocytes and natural killer cells) designed to destroy invaders; and (3) a group of proteins called the complement system, which are located throughout the body to protect against invaders.

Answer 83

Innate

Question 84

adapts to protect against almost any type of invading pathogen. The primary purpose of the acquired immune system is to provide protection against viruses that the innate immune system cannot combat directly. B­ and T­cells are the major cells involved in the acquired immune system. B­cells produce antibodies, whereas T­cells specialize in recognizing and removing antigens in the body.

Answer 84

Acquired immune system

Question 85

The relationship between the intensity/amount of exercise and the risk of developing a URTI is described as a

Answer 85

J shaped curve

Question 86

This J­shaped curve illustrates that moderate­intensity aerobic exercise decreases

Answer 86

Risk of infection

Question 87

heavy­intensity/prolonged exercise increases the risk of

Answer 87

infection

Question 88

Following heavy­intensity exercise, lower cell counts and activity of natural killer cells, T­cells, and B­cells appear to be directly related to the increased risk of

Answer 88

infection following heavy­intensity/long­duration bouts of exercise.

Question 89

Heavy­intensity/long­duration exercise has a temporary depressive effect on the

Answer 89

Immune system

Question 90

exercise in a hot environment does not pose a greater threat to immune function compared to exercise in a

Answer 90

Cool environment

Question 91

Prolonged high­altitude exposure (i.e., living in the mountains) combined with exercise can

Answer 91

increase the risk of URTI.

Question 92

It is not wise to exercise if cold symptoms are below the

Answer 92

Neck