Exam 1

Question 1

the study of how the body structure and function are altered by exposure to acute and chronic bouts of exercise

Answer 1

Exercise physiology

Question 2

the application of the concepts of exercise physiology to training athletes and enhancing sport performance

Answer 2

Sport physiology

Question 3

the study of the effects of the environment on the function of the body

Answer 3

Environmental physiology

Question 4

a single bout of exercise

Answer 4

Acute exercise

Question 5

a physiological change that occurs when the body is exposed to repeated exercise bouts over weeks or months. these changes generally improve the body’s efficiency at rest and during exercise

Answer 5

Chronic adaption

Question 6

tests the same subjects and compares results over time

Answer 6

Longitudinal research

Question 7

collects data from a diverse population and compares groups in that population

Answer 7

Cross-sectional research

Question 8

single alpha-motor neuron + all fibers it innervates

more operating motor units = more contractile force

Answer 8

Motor unit

Question 9

site of communication between neuron and muscle

consists of synapse between alpha-motor neuron and muscle fiber

Answer 9

Neuromuscular junction

Question 10

outer connective tissue covering

surrounds the entire muscle and functions to hold it together and give it shape

Answer 10

Epimysium

Question 11

a small bundle of muscle fibers wrapped in a connective tissue sheath within a muscle

Answer 11

fascicle

Question 12

the connective tissue sheath surrounding each muscle fascicle

Answer 12

Perimysium

Question 13

Muscle fiber contraction

Answer 13

1. Action potential (AP) starts in the brain
2. AP arrives at axon terminal release ACh
3. ACh crosses synapse, binds to ACh receptors on plasmalemma
4. AP travels down plasmalemma, T-tubules
5. Triggers Ca2+ release from sarcoplasmic reticulum
6. Ca2+ enables actin-myosin contraction
7. Myosin head attaches to binding site on actin
8. Energy from release of ADP + Pi causes the power stroke
9. ATP attaches to myosin head , and causes the disconnect
10. ATP is hydrolyzed to ADP and Pi and energy is restored
11. Cessation of action potential = return on Ca to TC via SR, and binding sites are covered

Question 14

a sheath of connective tissue that covers each muscle fiber

Answer 14

endomysium

Question 15

No actin-myosin interaction at binding site

myofilaments overlap a little

Answer 15

Relaxed State

Question 16

Myosin head pulls actin toward sarcomere center (power stroke)

filaments slide past each other

sarcomeres, myofibrils, muscle fibers all shorten

Answer 16

Contracted state

Question 17

an individual muscle fiber is surrounded by a plasma membrane

Answer 17

plasmalemma

Question 18

a muscle fiber’s cell membrane

Answer 18

sarcolemma

Question 19

gelatin-like substance that fills the spaces within the myofibrils

Answer 19

sarcoplasm

Question 20

extensions of the plasmalemma that pass laterally through the muscle fiber

Answer 20

T-tubules

Question 21

longitudinal network of tubules

Answer 21

Sarcoplasmic reticulum

Question 22

the basic functional until of a myofibril and the basic contractile unit of muscles

Answer 22

sarcomere

Question 23

order of recruitment of motor units directly related to size of alpha-motor neuron

Answer 23

Size principle

Question 24

optimal sarcomere length = optimal overlap

too short or too stretched = little or no force develops

Answer 24

Length-tension relationship

Question 25

maximal force development decreases at higher speeds

Answer 25

Concentric

Question 26

maximal force development increases at higher speeds

Answer 26

Eccentric

Question 27

the protruding part of a myosin filament. It includes the myosin head, which binds to an active site on an actin filament to produce a power stroke that causes the filaments to slide across each other

Answer 27

Myosin cross-bridge

Question 28

the tilting of the myosin head, caused by a strong intermolecular attraction between the myosin cross-bridge and the myosin head, that causes the actin and myosin filaments to slide across each other

Answer 28

Power stroke

Question 29

explaining muscle action: a myosin cross-bridge attaches to an actin filament, and then the power stroke drags the two filaments past one another

Answer 29

Sliding filament theory

Question 30

conscious control of skeletal muscle movement

Answer 30

Primary motor cortex (frontal lobe)

Question 31

clusters of cell bodies deep in cerebral cortex help initiate sustained or repetitive movements walking, running, posture, muscle tone

Answer 31

Basal ganglia (cerebral white matter)

Question 32

Maintains homeostasis, regulates internal environment Neuroendocrine control, appetite, food intake, thirst/fluid balance, sleep, BP, HR, breathing, body temp

Answer 32

Hypothalamus

Question 33

Controls rapid, complex movements coordinates timing, sequence of movements, compares actual to intended movements and initiates correction accounts for body position and muscle status receives input from the primary motor cortex, helps execute and refine movements

Answer 33

Cerebellum

Question 34

regulates visceral activity

Answer 34

Autonomic

Question 35

stimulates skeletal muscle activity

Answer 35

Somatic

Question 36

Fight or Flight Increases: HR, BP, blood flow to muscles, bronchodilation, metabolic rate, glucose levels, FFA levels, mental activity

Answer 36

Sympathetic Nervous System

Question 37

Rest and digest Increases digestion and urination conservation of energy decreases HR and diameter of vessels and airways

Answer 37

Parasympathetic Nervous System

Question 38

localized changes in the membrane potential, either depolarization or hyperpolarization triggered by a change in the neuron's environment

Answer 38

Graded potentials

Question 39

site of action potential transmission from the axon terminals of one neuron to the dendrites or soma of another

Answer 39

Synapse

Question 40

primary neurotransmitter for the motor neurons that innervate skeletal muscle as well as for most parasympathetic autonomic neruons

Answer 40

Acetylcholine

Question 41

Instant, preprogrammed response to a given stimulus response to stimulus identical each time occurs before conscious awareness

Answer 41

Motor reflex

Question 42

the process by which protein or fat is converted into glucose

Answer 42

Gluconeogensis

Question 43

the process of converting protein into fatty acids

Answer 43

Lipogenesis

Question 44

an enzyme found early in a metabolic pathway that determines the rate of the pathway

Answer 44

Rate-limiting enzyme

Question 45

the enzyme that facilitates the breakdown of PCr to creatine and Pi

Answer 45

Creatine kinase

Question 46

an energy-rich compound that plays a critical role in providing energy for muscle action by maintaining ATP concentration

Answer 46

Phosphocreatine (PCr)

Question 47

VCO2/VO2

Answer 47

Respiratory Exchange Ratio (RER)

Question 48

difference between oxygen required for a given exercise intensity and the actual oxygen consumption

Answer 48

Oxygen deficit

Question 49

the volume of oxygen consumed during minutes immediately after exercise ceases that is above that normally consumed at rest

Answer 49

Excess Postexercise Oxygen Consumption (EPOC)

Question 50

the point at which blood lactate begins to substantially accumulate above resting concentrations during exercise of increasing intensity (point where blood lactate first increases above resting)

Answer 50

Lactate threshold

Question 51

anchoring points of contact for contractile proteins

Answer 51

Sarcomere Z-disks