Exercise Physiology Chapters 1-5
cardiac muscle
A type of muscle tissue: Involuntary, heart -myocardium
skeletal muscle
A type of muscle tissue: Voluntary, skeleton -biceps
Smooth muscle
A type of muscle tissue: involuntary, hollow organs -small intestine
The H-zone is in the middle of the __- band and narrows during ____.
A, contraction
Which of these does not help increase plasma glucose concentrations during exercise?
ADH
The posterior pituitary gland contributes to fluid regulation via secretion of ____.
ADH (antidiuretic hormone)
14. The most important high energy phosphate compound in muscle cells is a. NAD b. FAD c. ATP d. STP
ATP
30. The energy required for muscle contraction is supplied by a. inorganic phosphate (Pi) b. ADP c. ATP d. ATPase
ATP
24. The two high-energy compounds critical for all physical activity are a. ATP and PCr b. AMP and PCr c. AMP and ADP d. ATP and ADP
ATP and PCr
23. What is the trigger mechanism to initiate contraction in skeletal muscle? a. calcium binding to troponin b. calcium binding to tropomysium c. calcium binding to myosin d. ATP binding to the myosin cross-bridge
ATP binding to the myosin cross-bridge
19. What hormone(s) play a major role in monitoring fluid levels along with regulating electrolyte balance?
Antidiuretic hormone (ADH). ADH promotes water conservation by increasing water permeability to kidneys. . Aldosterone & possibly renin.
The hypothalamus assists in the regulations of 8 physiological systems, including:
BP, respiration, digestion, body temp, thirst/fluid balance, neuroendocrine control, appetite/food intake, sleep-wake cycle
3. A sarcomere:
Basic functional unit of a myofibril & basic contractile unit of muscle. Composed of numerous sarcomeres joined end to end at the Z-disks. P. 29
75. Which of the following serve as buffers for the body?
Bicarbonate, inorganic phosphates, proteins, and maybe hemoglobin
decreases
Hormonal Regulation of Fluid and Electrolytes During Exercise: -at onset of exercise, water shifts from the plasma volume to the interstitial and intracellular spaces. -all the effects result in a __ of plasma volume. -reduced plasma volume can decrease blood pressure and increase the strain on the heart to pump blood to the working muscles, which can impede performance.
anterior pituitary gland; thyroid gland; adrenal gland; pancreas
Hormonal Regulation of Metabolism During Exercise: -the major glands involved are: --__ --__ --__ --__
Anterior Pituitary Gland
Hormonal Regulation of Metabolism During Exercise: __ -also called adenohypophysis -the hormones released are controlled by hormones secreted from the hypothalamus -secretes 6 hormones in repose to hormones from hypothalamus -hormones sent here are either releasing or inhibiting factors -exercise increases the release of most of their hormones bc exercise is a strong stimulus to the hypothalamus
adrenal medulla; catecholamines; both
Hormonal Regulation of Metabolism During Exercise: adrenal glands -composed of inner adrenal medulla and outer adrenal cortex -the __ produces and releases epinephrine (adrenaline) and norepinephrine, which are collectively called __. -plasma norepinephrine concentrations increase markedly at intensities above 50% of VO2max, but epinephrine concentrations do not increase significantly until the exercise intensity exceeds 60-70% of VO2max. -during long duration steady state exercise at a moderate intensity, blood concentrations of __ increase.
adrenal cortex; cortisol
Hormonal Regulation of Metabolism During Exercise: adrenal glands -composed of inner adrenal medulla and outer adrenal cortex -the __ secretes more than 30 different steroid hormones, referred to as corticosteroids -3 major types of corticosteroids: --mineralocorticoids, glucocorticoids, and gonadocorticoids -__, also called hydrocortisone, is the major corticosteroid.
insulin; glucagon; insulin; glucagon
Hormonal Regulation of Metabolism During Exercise: pancreas -two major hormones are __ and __. -the balance of these two opposing hormones provides the major control of plasma glucose concentration. -during exercise lasting 30 mins or longer, __ concentrations tend to decline, and plasma __ shows a gradual increase throughout exercise.
triiodothyronine (T3); thyroxine (T4); calcitonin
Hormonal Regulation of Metabolism During Exercise: thyroid gland -secretes __, __, and __.
different; endurance; power/sprinters; soleus
Distribution of fiber types: -each person has __ ratios -arm and leg ratios are similar in one person: --__ athlete: type I predominates --__ athlete: type II predominates -__: type I in everyone
74. Respiration
Does not generally limit performance in healthy individuals.
excess postexercise oxygen consumption (EPOC)
Elevated oxygen consumption above resting levels after exercise; at one time referred to as oxygen debt
posterior pituitary; adrenal cortex; kidneys
Endocrine Glands Involved in Fluid and Electrolyte Homeostasis: -what are the endocrine glands involved in this?
mineralocorticoids; aldosterone
Endocrine Glands Involved in Fluid and Electrolyte Homeostasis: Adrenal Cortex -a group of hormones called __, maintain electrolyte balance, especially that of Na+ and K+ in the extracellular fluids. -__ is the major mineralocorticoid, responsible for at least 95% of all mineralocorticoid activity.
antidiuretic hormone (ADH, vasopressin, or arginine vasopressin); oxytocin
Endocrine Glands Involved in Fluid and Electrolyte Homeostasis: Posterior Pituitary -"neurohypophysis": bc is an outgrowth of neural tissue from the hypothalamus. -secretes two hormones: __ and __. -both hormones produced in hypothalamus and then stored in vesicles within nerve endings in the posterior pituitary.
myosin; ADP; Pi
Energy for Muscle Contraction: -ATP binds to myosin head --ATPase on __ head breaks down ATP --ATP-> __ + __ +energy for head tilt -necessary for muscle contraction -thin filament past thick filament
epimysium; bundles
Entire muscle: -surrounded by connective tissue called __. gives muscle shape and holds it together. -consists of many __ (fasciculi)
12. Beta oxidation is the name for
Enzymatic catabolism of fat by the mitochondria, FFA's enter muscle fiber
y-axis
In a graph the __ is the D pendant variable that will change depending on how the independent variable is manipulated
X - axis
In a graph the __ is the independent variable or factor that is controlled by the study design
66. At very high heart rates during cardiorespiratory endurance exercise, stroke volume may decrease because of
Inadequate ventricular filling resulting from a shortening diastole.
63. Of the following factors, which is considered the most important contributor to the improvement in stroke volume with endurance training?
Increased blood volume
(Ch 7) 61. Which of the following would cause a decrease in stroke volume?
Increased hematocrit, increase after-load decreased pre-load,
transition
Interaction of the Energy Systems: -all 3 systems interact for all activities --no one system contributes 100%, but --one system often dominates for a given task -more cooperation during __ periods
Which of these is not a second messenger?
K+ ions
VO2 max is measured in_____ for non-weight bearing activities
L/min
13. Which of the following measurements is necessary when assessing the rate of protein metabolism by the body?
- Amount of nitrogen eliminated from body must be determined (can be found in urine)
graded potentials
-triggered by localized changes in the membrane potential such as changes in chemical concentrations, temperature, or pressure. -either depolarization or hyperpolarization occurs -does not spread very far along the neuron
PCr
-used for short-term high-intensity effort, to rebuild ATP as it is used and thus to maintain ATP stores within the muscle. -controlling the rate of effort through pacing can help to ensure that these stores and ATP stores do not run out too quickly at the beginning
calorie (cal)
1 __ = heat energy required to raise 1g of water from 14.5 celsius to 15.5 celsius
lactic acid; O2; oxidative
Glycolytic System: -Cons: --low ATP yield, inefficient use of substrate --lack of O2 converts pyruvic acid to lactic acid --__ acid impairs glycolysis and muscle contraction -Pros: --allows muscles to contract when __ limited --permits shorter-term, higher-intensity exercise than __ metabolism can sustain
(Ch 3) 21. A localized change in a neuron's membrane potential, which may or may not spread over the entire cell membrane, is called
Graded potential
oxidative phosphorylation
ATP producing reaction that is aided by oxygen
ATPase breaks down ___ which releases ____, which is used in the formation and breaking down of ____-_____ bridges
ATP, energy, action-myosin
16. The simplest and most rapid method to generate ATP is through a. glycolysis b. ATP/PCr system c. glycogenolysis d. aerobic metabolism
ATP/PCr system
35. The velocity of nerve impulse transmission in large myelinated fibers can approach a. 25 miles per hour b. 50 miles per hour c. 100 meters per second d. 250 meters per second
100 metres per second
Type I has the contraction speed of __ ms, ___ force production, ___ fatigue resistance, smaller fiber size, and ___ reliance on aerobic metabolism.
110, low, high, high
18. The net ATP production from anaerobic glycolysis if you start with glucose is a. 2 ATP, which occurs in the cytoplasm b. 3 ATP, which occurs in the mitochodria c. 2 ATP, which occurs in the mitochondria d. 3 ATP, which occurs in the cytoplasm
2 ATP, which occurs in the mitochondria
29. Muscle contraction requires energy. Which of the following is (are) correct? a. ATP provides this energy to activate the myosin cross-bridges before binding with actin. b. ATP provides the energy leading to relaxation between the myosin heads and the binding sites. c. The energy provided by the breakdown of ATP requires ATPase. d. All of these are correct.
All of these are correct
33. Steroid hormones a. include hormones such as estrogen and testosterone b. are soluble in lipids c. diffuse easily across cell membranes d. All of these are correct.
All of these are correct
43. What factors influence force production? a. number and type of motor units activated b. size of the muscle c. muscles' initial length when activated d. angle of the joint e. All of these are correct.
All of these are correct
5. Energy is needed for a. growth and repair of tissues b. active transport of substances across cell membranes c. muscle contraction and force production d. All of these are correct.
All of these are correct
9. Sarcoplasm a. is the fluid part of the muscle fiber b. contains dissolved protein, minerals, glycogen, fat, and organelles c. contains myoglobin d. All of these are correct.
All of these are correct
What happens to metabolic rate as exercise intensity inc.
MR inc. and therefore O2 uptake increases quicker and is larger
What else is needed if there is more carbon atoms in a molecule
More O2
1. The multiple functions of the muscular system are performed by ____ type(s) of muscle. a. 2 b. 3 c. 4 d. 1
3
renin; erythropoietin
Although the kidneys are not typically considered major endocrine organs, they do release what two important hormones?
Haldane transformation
An equation allowing one to calculate the inspired air volume from expired air volume or expired air volume from inspired air volume
8. What factors influence force production?
Optimal sarcomere length for overlap, type II generates more force because of more muscle fibers, summation to tetanus to peak face
glycolysis; krebs cycle; electron transport chain
Oxidation of Carbohydrate: 1) __ 2) __ 3) __
glycolysis; same; Krebs
Oxidation of Carbohydrate: glycolysis revisited -__ can occur with or without O2 --ATP yield __ as anaerobic glycolysis --same general steps as anaerobic glycolysis, but int he presence of oxygen, pyruvic acid -> acetyl-CoA, enters __ cycle
triglycerides; concentration; slower
Oxidation of Fat: -__: major fat energy source --broken down to 1 glycerol + 3 FFAs --lipolysis, carried out by lipases -rate of FFa entry into muscle depends on __ gradient -yields 3 to 4 times more ATP than glucose -__ than glucose oxidation
gluconeogenesis; acetyl-CoA
Oxidation of Protein: -rarely used as a substrate --starvation --can be converted to glucose (__) --can be converted to __ -energy yield not easy to determine --nitrogen presence unique --nitrogen excretion requires ATP expenditure --generally minimal, estimates therefore ignore protein metabolism
What is the relationship between O2 consumption and energy production?
O2 is required to breakdown substrates for energy; increased 02 consumption means being able to break down more substrate and being able to break down substrates quicker .:. being able to provide more energy for exercise and burning more calories
What causes fatigue (4)
PcR/glycogen depletion-inadequate ability to make ATP, accumulation of metabolic by-products (lactate and H+), failure of the mm fiber's contractile mechanism, altered neural control
39. Fatigue due to failure to deliver adequate energy, accumulation of metabolic by-products, or failure of the muscle fiber's contractile mechanism is best termed
Peripheral fatigue
what is a potential cause of PcR depletion
Pi accumulation
Metabolic by-products that are implicated in fatigue
Pi, heat, lactic acid, H+ Lactic acid
respiratory exchange ratio (RER)
Ratio of carbon dioxide expired to oxygen consumed at the level of the lungs -may not accurately estimate the type of fuel being used by the muscles
alpha motor neurons; motor unit
Motor units: -__: nerve cells that connect with and innervate muscle fibers -one __ is a single motor neuron and all the fibers it innervates -more operating motor units = more contractile force.
type I; type IIa; type IIx
Recruit minimum number of motor units needed: -smallest (__) motor units recruited first -midsized (__) motor units recruited next -largest (__) motor units recruited last recruited in same order each time
potassium ions; sodium ions
Resting Membrane Potential (RMP): -neuron at rest = -70mV -polarized bc charges differ -high concentration of __ on inside -high concentration of __ on outside
42. The AV node intrinsically regulates heart rate at 40 to 60 bpm, often necessitating the insertion of an artificial pacemaker. SA node about 100 bpm, higher in Heart higher bpm p. 127
SA node make the sinus rhythm. The AV node delays the impulse from the SA node What is the question here?
25. Which of the following is incorrect? a. The A-band contains both thick and thin filaments and the thick filaments run the entire length of the A-band. b. The tilting of the myosin head dragging actin toward the center of the sarcomere is called the power stroke. c. Troponin covers the myosin binding sites on actin, preventing the binding of myosin. d. Any time depolarization reaches or exceeds the threshold, an action potential will result.
Troponin covers the myosin binding sites on actin, preventing the binding of myosin
73. (T/F) Lactate threshold can be estimated with reasonable accuracy by identifying that point at which the ventilatory equivalent of oxygen starts to increase while the ventilatory equivalent of carbon dioxide continues to decline.
True
T/F: Steroid hormones can diffuse through the cell membranes and attach to receptors located somewhere inside the cell.
True
T/F: The anterior pituitary, thyroid gland, adrenal glands, and pancreas are the major endocrine glands responsible for regulating metabolism.
True
T/F: The renin-angiotensin-aldosterone system helps restore blood volume and blood pressure by a combination of systemic vasoconstriction and Na+ (followed by water) retention by the kidneys.
True
T/F: The thyroid hormones T3 and T4 share many similar metabolic functions, including enhancing glycolysis and lipid mobilization.
True
T/F: When solutes (such as Na+) move from one fluid compartment to another, water usually follows due to osmosis.
True
9. During a progressive increase in exercise intensity, motor units with small motor neurons are recruited first.
True, as intensity increases the number of fibers recruited increases in the following order, in an addidative manner: type I--> type IIa -->type IIx p. 40
10. Rate coding is the term used to describe the process by which the tension of a given motor unit can vary from that of a twitch to that of tetanus by increasing the frequency of stimulation of that motor unit.
True, p. 43
22. Action potentials cannot be generated even if a threshold is not met.
True.
inside; hormone-receptor complex; direct gene activation; nucleus; protein synthesis
Steroid Hormones: 1) the steroid hormone binds to receptor __ the cell, either the cytoplasm or nucleus 2) the __ activates the cell's DNA via __. 3) this causes mRNA to be synthesized within in the __. 4) mRNA then enters the cytoplasm and promotes __.
glycogen depletion; hypoglycemia (low blood sugar)
__ and __ limit performance in activities lasting longer than 60 to 90 minutes
triiodothyronine (T3); thyroxine (T4); thyroxine; triiodothyronine
__ and __: -can increase the metabolic rate of almost all tissues and can increase the body's basal metabolic rate by as much as 60-100% -release is controlled by thyrotropin (TSH) from anterior pituitary -during prolonged submaximal exercise, __ concentration increases sharply and then remains relatively constant while __ concentrations tend to decrease over time
inorganic phosphate
__ increases and accumulates during intense short-term exercise. -may be the largest contributor to fatigue for intense short-term exercise
lactate; mitochondria; MCP; recirculate
__ is an important fuel during exercise. Muscles can utilize lactate in 3 ways: -lactate produced in cytoplasm can be taken up by the __ of the same muscle fiber and oxidized. -lactate can be transported via __ transporters to another cell and oxidized there (lactate shuttle) -lactate can __ back to the liver, reconverted to pyruvate and then to glucose through gluconeogenesis.
negative feedback; isocitrate dehydrogenase
__ regulates Kreb's cycle. __: rate-limiting enzyme -similar to PFK for glycolysis -regulates ETC -inhibited by ATP, activated by ADP
prostoglandins; autocrines
__: -hormone that act as local hormones or __, exerting their effects in the immediate are where they're produced. -can be triggered by hormones or local injury -important mediators for the inflammatory response and pain -sensitize the nerve endings of pain fibers
beta oxidation; carbons
__: The first step in fatty acid oxidation in which fatty acids are broken into separate two carbon units of acetic acid each of which is then converted to acetyl CoA -requires up-front expenditure of 2 ATP -number of steps depends on number of __ on FFA --16 carbon FFA yields 8 acetyl-CoA --compare: 1 glucose yields 2 acetyl-CoA --fat oxidation requires more O2 now, yields far more ATP later Acetyl CoA is the common intermediate through which all substrates enter the Krebs cycle for oxidative metabolism
Sliding Filament Theory; active site; original; attaches; Z-disk; SR
__: How muscles create movement -after power stroke ends: --myosin detaches from __. --myosin head rotates back to __ position --myosin __ to another active site farther down -process continues until: --__ reaches myosin filaments or --AP stops, Ca2+ gets pumped back into __.
15. Viewed under a microscope, striations can be observed in a. cardiac muscle b. smooth muscle c. skeletal muscle d. a and c
a and c
19. Which of the following are true concerning the thick filaments? a. They are composed of globular heads forming cross-bridges for muscle action. b. They are composed of troponin and tropomyosin. c. Thick filaments are known as myosin filaments. d. a, b, and c e. a and c
a and c
51. Which statement is true about the pancreatic hormones and exercise? a. Physical training decreases a person's sensitivity to insulin. b. Physical training lowers the insulin requirement. c. Exercise requires a larger insulin output to clear excess glucose compared to rest. d. Physical training causes insulin and glucagon in the blood to be higher than resting values. e. a and c
a and c
56. What hormone(s) play a major role in monitoring fluid levels along with regulating electrolyte balance? a. antidiuretic hormone b. cortisol c. aldosterone d. a and c
a and c
calorimeter
a device for measuring the heat produced by the body (or by a specific chemical reaction)
muscle spindle
a group of specialized muscle fibers found between regular skeletal muscle fibers (extrafusal fibers). -consists of 4-20 intrafusal fibers and the nerve endings, sensory and motor, associated with these fibers
phosphofructokinase (PFK)
a key rate-limiting enzyme of the anaerobic glycolytic energy system -low ATP, higher PFK activity -high ATP, lower PFK activity -also regulated by products of Krebs cycle
direct calorimetry
a method that gauges the body's rate and quantity of energy production by direct measurement of the body's heat production. -pros: can provide accurate measure of total body energy expenditure over time. useful for measuring resting metabolism and energy expended during prolonged, steady state aerobic exercise -disadvantages: cannot follow rapid changes in energy time expenditure. therefore, energy metabolism during more typical exercise situations cannot be adequately studied with these
27. When an excitatory neural impulse from one neuron is transmitted to a second neuron, it is called
a nerve impulse.
32. Fast-twitch fibers contain a. a relatively large number of mitochondria and low ATPase activity b. a relatively small number of mitochondria and low ATPase activity c. a relatively small number of mitochondria and high ATPase activity d. None of these is correct.
a relatively small number of mitochondria and high ATPase activity
47. Tachycardia is generally defined as
a resting rate greater than 100 beats/min
electron transport chain
a series of chemical reactions that convert the hydrogen ion generated by glycolysis and the Krebs cycle into water and produce energy for oxidative phosphorylation
krebs cycle
a series of chemical reactions that involve the complete oxidation of acetyl CoA and produce 2 mol of ATP along with hydrogen and carbon, which combine with oxygen to form water and CO2
cytochrome
a series of iron-containing proteins that facilitate the transport of electrons within the electron transport chain
VO2 drift
a slow increase in VO2 during prolonged submaximal exercise at a constant power output -unlike the slow component, this is observed at power outputs well below lactate threshold, and the increase in VO2 drift is more gradual.
Vo2 drift
a slow increase in VO2 during prolonged, submaximal, constant power output activity; observed well below lactate threshold, magnitude of increase of VO2 drift is much less than VO2max
48. A muscle action in which the muscle generates force but does not change in length is called a. a static action b. a concentric action c. an eccentric action d. a passive action
a static action
glucocorticoids
a steroid hormone that is released from the adrenal cortex. essential to the ability to adapt to exercise and other forms of exercise p.106
calorie
a unit of measure of energy in biological systems, where 1.0 calorie is equal to the amount of heat energy needed to raise the temperature of 1g of water 1 degree, from 15 to 16 degrees Celsius. -basic unit of heat
16. A sarcomere a. is the smallest functional unit of skeletal muscle b. is found between two Z-discs c. contains actin and myosin d. a, b, and c e. a and c
a, b, and c
36. Cyclic AMP a. acts as a second messenger in non-steroidal hormone receptor responses b. acts as a second messenger in steroidal hormone receptor responses c. exerts its action by stimulating messenger RNA d. blocks the effect of a released hormone
acts as a second messenger in non-steroidal hormone receptor responses
Aldosterone release from the _____ leads to _____ in the kidneys.
adrenal cortex, Na+ retention
Although the fight-or-flight response is often associated with the sympathetic nervous system, it is also associated with the effects of hormones secreted from the ____.
adrenal gland (adrenal medulla)
Which of these glands is not associated with steroid hormone production?
adrenal medulla
Type I is related to ____ metabolism (i.e waiting
aerobic
32. Nerve fibers that carry impulses toward the central nervous system are called a. efferent fibers b. dendrites c. afferent fibers d. None of these is correct.
afferent fibers
after how long of training does VO2 max plateau
after 8-12 weeks of training, however- performance continues to improve
When are type I fibers depleted
after moderate endurance exercise
An increase in plasma osmolality is the stimulus for release of ___.
aldosterone
Two major steroid hormones secreted by the adrenal cortex are ____ and ____.
aldosterone, cortisol
What are the adrenal hormones?
aldosterone, cortisol, norepinephrine
37. Which of the following factors influences your basal metabolic rate? a. heat stress b. emotional stress c. body size d. all of these
all of these
28. The specialized collection of neurons in the brain stem, known as the reticular formation, functions to a. coordinate skeletal muscle function b. maintain muscle tone c. control cardiovascular and respiratory functions d. determine our state of consciousness (both arousal and sleep) e. All of these are correct.
all of these are correct
31. The sensory division of the peripheral nervous system a. carries sensory information toward the central nervous system b. functions using afferent nerves c. receives information from chemoreceptors d. receives information from mechanoreceptors e. All of these are correct.
all of these are correct
46. Triiodothyronine and thyroxine a. increase metabolic rate of almost all tissues b. increase protein synthesis c. increase the size and number of mitochondria in most cells d. All of these are correct.
all of these are correct
47. A concentric muscle contraction is one in which a. the muscle shortens as a contractile force is generated b. there is joint movement as tension is developed c. during a biceps curl the bar is raised in contrast to lowering the bar d. all of these are correct
all of these are correct
47. Catecholamines a. prepare the body for the flight or fight response b. include epinephrine and norepinephrine c. function to increase heart rate and force of contraction d. increase metabolic rate e. All of these are correct.
all of these are correct
metabolism
all the chemical reactions in the body collectively called this
thyroxine; triiodothyronine; epinephrine; norepinephrine
amino acid derived hormones: -__ and __ from thyroid gland -__ and __ from adrenal medulla
Nonsteroid hormones are characteristically ____.
amino acid/protein based
45. A muscle that provides most of the force required for a given movement is referred to as a. a synergist b. an antagonist c. a fixator d. an agonist
an agonist
nebulin
an anchoring protein for actin, coextends with actin and appears to play a regulatory role in mediating actin and myosin interactions
phosphocreatine (PCr)
an energy-rich compound that plays a critical role in providing energy for muscle action by maintaining ATP concentration -cannot be used for cellular work but is used to reassemble ATP -regenerates ATP to maintain a relatively constant supply under resting conditions -recycles ATP during exercise until used up (3 to 15s max exercise)
Haldene transformation
an equation allowing one to calculate the inspired air volume from expired air volume or expired air volume from inspired air volume * volume of nitrogen inspired is equal to volume of nitrogen expired*
59. A decrease in plasma volume and an increase in osmolality of plasma during exercise results in what change in antidiuretic hormone? a. an increase b. a decrease c. no change
an increase
55. To increase the rate of lipolysis, which of the following must occur? a. an increase in insulin b. a decrease in cortisol c. an increase in epinephrine d. a decrease in growth hormone e. All of these changes lead to increased lipolysis.
an increase in epinephrine
What is lactate a by-product of
anaerobic respiration
Type II can be either _____metabolism (i.e. starting a sprint), or ____metabolism (i.e. long distance running)
anaerobic, aerobic
The ____ gland is sensitive to hypothalamic releasing and inhibiting factors.
anterior pituitary
nerve impulse
arises when a stimulus is strong enough to change the normal electrical charge of the neuron
58. The carotid bodies are chemoreceptors that are sensitive primarily to changes in
arterial PO2 but also respond to changes in H+ concentration and PCO2
economical
as people become more skilled at performing an exercise, the energy demands during exercise at a given pace are reduced. in a sense, people become more __. ex: two people have the same VO2max values, but the one that needs the least amount of oxygen the complete the task is more economical.
The temporal lobe is responsible for _____ input and interpretation.
auditory
How is RER used to determine oxidation of fats and carbohydrates
The amount of O2 used during metabolism depends on the type of fuel being oxidized; in general the amount of O2 needed to oxidize a molecule of CHO or Fat is proportional to the amount of carbon in that fuel. By finding how much CO2 molecules is released compared to amount of O2 released we can calculate RER Carb: 1.0 Fat: 0.7 Protein: 0.82
27. The lower part of the brain that is made up of bundles and tracts of nerves traveling down to the spinal cord and composed of the midbrain, the pons, and the medulla oblongata is called the a. cerebrum b. cerebellum c. brainstem d. diencephalon
brainstem
Epinephrine and glucagon often activate ____, a second messenger molecule, to bring about changes in enzyme activity, membrane permeability, protein synthesis, or cellular metabolism.
cAMP (cyclic adenosine monophosphate)
7. Which of the following is considered to be the major source of energy for running a 440-yard race? a. carbohydrate b. fat c. protein d. B-vitamins
carbohydrate
6. The higher the intensity of the exercise, the more the body relies on a. fat as an energy source b. carbohydrate as an energy source c. protein as an energy source d. Fat and carbohydrate are used equally
carbohydrate as an energy source
2. The food sources from which we derive energy are composed mainly of a. carbon, calcium, nitrogen, and sodium b. carbon, hydrogen, oxygen, and phosphorus c. calcium, hydrogen, nitrogen, and sodium d. carbon, hydrogen, nitrogen, and oxygen
carbon, hydrogen, nitrogen, oxygen
What is the primary substrate used to provide energy during high intensity exercise?
carbs
Epinephrine and norepinephrine are collectively known as ____.
catecholamines
Which group of hormones exerts metabolic and cardiovascular effects during exercise?
catecholamines
4. Neurons can be divided into 3 basic parts: a. cell body, soma, and axon b. soma, dendrites, and Schwann cells c. cell body, dendrites, and axon d. afferent, efferent, and dendrites
cell body, dendrites, and axon
downregulation
cells sensitivity to a hormone decreases because the cell membrane contains less receptors.
upregulation
cells sensitivity to a hormone increases because the cell membrane contains more receptors.
As the rate of lipolysis increase, _____.
cellular FFA uptake increases
mitochondria
cellular organelles that generate ATP through oxidative phosphorylation
30. The posterior outpocketing of the brain that is primarily concerned with coordination of movement and balance is called the a. cerebrum b. brain stem c. cerebellum d. diencephalon
cerebellum
44. Which of the following areas within the central nervous system appears to be particularly important in coordinating body movements? a. hypothalamus b. primary motor cortex c. cerebellum d. spinal cord
cerebellum
45. Motor impulses for complex movement patterns (such as throwing a baseball or writing on a chalkboard) typically originate at the level of the a. cerebral cortex b. brain stem c. spinal cord d. thalamus
cerebral cortex
34. The primary motor cortex, the basal ganglia, and the primary sensory cortex are all located in the a. cerebrum b. cerebellum c. diencephalon d. pons
cerebrum
Chemoreceptors respond to ______ stimuli such as foods, odors, changes in blood/tissue concentrations of substances (oxygen, CO2, glucose, electrolytes).
chemical
36. Sensory receptors that respond to changes in blood concentrations of CO2, O2, and glucose are referred to as a. nociceptors b. mechanoreceptors c. kinesthetic receptors d. chemoreceptors
chemoreceptors
28. Sensory receptors that respond to changes in blood concentrations of CO2, O2, and glucose are referred to as
chemoreceptors.
Steroid hormones are derived from _____, which makes them ____ soluble.
cholesterol, lipid (fat)
38. NAD and FAD are a. enzymes that catalyze chemical reactions in glycolysis b. enzymes that catalyze chemical reactions of the Krebs cycle c. coenzymes that transfer hydrogens to the electron transport chain d. two important end products of oxidative phosphorylation
coenzymes that transfer hydrogens to the electron transport chain
The neuromuscular junction is the site of ________ between ____ neurons and muscle _____.
communication, motor, fibers
Fatigue
The inability to perform at max level due to the alteration of multiple physiological processes
activation energy
The initial energy required to start a chemical reaction or chain of reactions
maximal oxygen uptake (VO2max)
The maximum capacity for oxygen consumption by the body during maximal exertion. It is also known as aerobic power, maximal oxygen intake, maximal oxygen consumption, and cardiorespiratory endurance capacity
72. Ventilatory threshold is
The point at which ventilation begins to increase disproportionately to the increase in oxygen consumption.
lactate threshold
The point during exercise of increasing in intensity at which blood lactate begins to accumulate above resting levels were lactate clearance is no longer able to keep up with lactate production. -many investigators consider this a good indicator of an athlete's potential for endurance exercise -when the rate of lactate production exceeds the rate of lactate clearance -major determinant of the fastest pace that can be tolerated during a long term endurance event. person with highest lactate threshold usually exhibits the best endurance performance
38. Which of the following physiological changes is elicited by parasympathetic stimulation? a. increased heart rate b. increased sweating c. dilation of coronary blood vessels d. constriction of bronchial airways
constriction of bronchial airways
what happens if lactate is not cleared immediately
converted to H+, which causes an accumulation and also acidosis
52. What hormone works with glucagon to enhance gluconeogensis to provide more fuel during prolonged exercise? a. cortisol b. insulin c. antidiuretic hormone d. growth hormone
cortisol
67. The actual shortening of muscle during muscle contraction is due to the action of____ ______, which enable the thin filaments to slide past the thick filaments.
cross-bridges
Possible causes of altered neural transmission
dec. ACh synthesis and release, altered ACh breakdown in synapse, inc in mm fiber stimulus threshold (must depolarize for mm action), altered mm resting membrane potential
41. Prostaglandins a. primarily exert their effect in the immediate area in which they are produced b. decrease vascular permeability c. cause vasoconstriction d. decrease pain and inflammation
decrease vascular permeability
60. Based on what you have learned about the respiratory system, voluntary hyperventilation would
decrease ventilator drive and result in a decrease in alveolar and arterial carbon dioxide
58. Aldosterone secretion may be stimulated by a. decreased plasma sodium b. increased blood volume c. increased blood pressure d. decreased plasma potassium concentration
decreased plasma sodium
During prolonged exercise, T3 ____ while T4 ____.
decreases, plateaus
6. Which of the following is usually the first part of the neuron to receive an impulse from an adjacent neuron? a. soma, or cell body b. dendrites c. axon d. synapse
dendrites
List the components of a motor unit (6)
dendrites, alpha motor neuron, axon hillock, axon terminal, myofibrils, motor end plate
Radiating out from the cell body are the 2 cell processes: _____ and the ______.
dendrites, axon
9. Anytime the charge difference between the inside and outside of the cell drops below 70 mV or moves closer to zero, it is called a. hyperpolarization b. irritability c. depolarization d. conductivity
depolarization
23. The membrane voltage at which a graded potential becomes an action potential is called the
depolarization threshold.
55. When a decrease in muscle or blood pH causes increased unloading of O2 from hemoglobin, this is an example of
desaturation of O2 from hemoglobin for delivery into metabolically active tissue
A steroid hormone-receptor complex binding to DNA and activating certain genes is called _____.
direct gene activation
42. When an increased amount of hormone causes a decreased number of cell receptors available to the hormone, the cell becomes less sensitive and this is called a. negative feedback b. positive feedback c. down regulation d. pp regulation
down regulation
Cells will often under go receptor ____, where they decrease the umber of receptors for a particular hormone, making the cell less sensitive to that hormone.
downregulation
when does lactic acid accumulate
during brief, high-intensity exercise
hemodilution
during the early phases of plasma volume expansion due to increased exercise, hemoglobin concentration decreases because the retention of fluids.
50. Isotonic muscle contraction is a. dynamic b. static
dynamic
66. Lowering a heavy weight from the fully flexed to the fully extended position in the two-arm curl is an example of a(n) ___ muscle contraction.
eccentric
68. A muscle is capable of producing its greatest force during a(n) ______ contraction
eccentric
Photoreceptors respond to ________ radiation, like light, to vision.
electromagnetic
The insula lobe is responsible for diverse functions usually linked to _____ and ____-_____.
emotion, self-perception
(Ch 5) 41. The heart receives its nervous control from
The vagus nerve (sympathetic and parasympathetic nervous system aka autonomic nervous system)
The endocrine gland is apart of the ____ system that secretes ____ directly into the ____ rather than through a duct.
endocrine, hormones, blood
6. The connective tissue sheath that surrounds an individual skeletal muscle fiber is called the a. perimysium b. sarcomysium c. epimysium d. endomysium
endomysium
The _____ surrounds muscle fibers
endomysium
indirect calorimetry
energy expenditure measured by measuring exchange of respiratory gases produced via oxidative metabolism (rates of O2/CO2 exchanged in lungs equals rate of their usage and release by body tissue)
PCr role is to provide ___ (ATP) without the use of ____ (anaerobic)
energy, oxygen
terminal cisternae
enlarged areas of the sarcoplasmic reticulum surrounding the transverse tubules.
succinate; citrate
enzyme activity: -not all muscles exhibit optimal activity of oxidative enzymes -enzyme activity predicts oxidative potential -representative enzymes --__ dehydrogenase --__ synthase -endurance trained vs untrained
5. The layer of connective tissue surrounding the outside of the muscle is called a. perimysium b. endomysium c. sarcomysium d. epimysium
epimysium
The principal neurotransmitter of the sympathetic nervous system is ________ and _______.
epinephrine, norepinephrine
Which of the following is not an adrenal hormone?
erythropoietin
Kidneys are responsible for secreting _____, which stimulates red blood cell production, and the enzyme ____.
erythropoietin, renin
No activity is 100% aerobic or anaerobic, anaerobic estimates involve..
excess postexcercise O2 consumption, lactate threshold
What does mm fiber recruitment depend on: I, IIa, IIx
exercise intensity
A key characteristic of prostaglandins is that they ___.
exert their effects locally
O2 and CO2 measurement volumes
expired O2 concentration is less than the inspired CO2 concentrations are higher in expired air than in inspired
24. It is----- that only when the sum of all individual action potentials meets or exceeds threshold can a graded potential occur.
false
46. The cell membrane of a neuron at rest has a negative electrical potential of about 700 mV. a. true b. false
false
50. Only when the sum of all individual action potentials meets or exceeds threshold can a graded potential occur. a. true b. false
false
54. The individual muscle fibers within a skeletal muscle typically extend the entire length of the muscle. a. true b. false
false
55. The main role of the cerebellum is to modulate ascending pain impulses. a. true b. false
false
56. The contractile units of a skeletal muscle are called myofibrils. a. true b. false
false
58. Golgi tendon organs monitor the length of a muscle, whereas muscle spindles are sensitive to tension in the muscle-tendon complex. a. true b. false
false
59. The cerebellum is responsible for initial motor commands, whereas the motor cortex is responsible for smoothing out movements that would otherwise be jerky and uncontrolled. a. true b. false
false
60. The motor nerves that innervate skeletal muscles release norepinephrine. a. true b. false
false
61. Fast-twitch and slow-twitch muscle fibers having the same diameter generate the same amount of power. a. true b. false
false
62. Muscles controlling fine movements, such as those controlling the eyes, have a vast number of muscle fibers per motor neuron, whereas muscles with more general functions have only a small number of fibers per motor neuron. a. true b. false
false
64. Afferent fibers carry neural signals from the brain and upper spinal cord down to end organs such as muscles and glands. a. true b. false
false
65. Amino acids are the primary source of energy during sprint exercise. a. true b. false
false
65. Neurons of larger diameter conduct nerve impulses faster than neurons of smaller diameter because larger neurons present more resistance to local current flow. a. true b. false
false
66. The process of breaking down liver or muscle glycogen into glucose-1-phosphate is referred to as glycogenesis. a. true b. false
false
67. Endurance-trained muscles have oxidative enzyme activities that are somewhat less than those seen in untrained subjects. a. true b. false
false
Type II muscle fibers are ___-oxidative and glycolytic, fatigue easily. Used for explosive, ___- intensity events.
fast, high
32. For each liter of oxygen consumed by the body, which substrate provides the greatest number of kcal of energy? a. protein b. fat c. carbohydrate d. All three provide the same number of kcal.
fat
What is the primary substrate used to provide energy at rest?
fat
8. Which of the following statements is true regarding the relative roles of fat, carbohydrate, and protein as energy sources for cellular metabolism? a. Much more energy is stored in the body in the form of carbohydrate than in the form of fat. b. Protein is the predominant fuel source during exercise c. Fat cannot provide all of the energy required for high-intensity muscular activity because the rate of energy release from fat is too slow. d. Since glycogen reserves in the body are so large, only limited amounts of carbohydrate are needed in the daily diet.
fat cannot provide all of the energy required for high-intensity muscular activity because the rate of energy release from fat is too slow
triglycerides
fat is in the form of __ when it is in its most complex form. contains glycerol and 3 fatty acids. stored in fat cells and between and within skeletal muscle fibers
MM glycogen depletion + hypoglycemia=
fatigue
No cross-bridging may occur from
fatigue that inhibits Calcium release form SR
fine motor control
fewer fibers per motor unit -like muscles in the eye
insulin resistance
fewer insulin receptors on the cell membrane than normal amount so the body has to produce more insulin to maintain a normal plasma glucose level.
not
fiber type __ sole predictor of success: -cardiovascular function -motivation -training habits -muscle size
21. Before fat can be metabolized by the muscle cells, it must first be broken down into a. free fatty acids and glycogen b. free fatty acids and glycerol c. triglycerides and glucose d. amino acids and glycerol
free fatty acids and glycerol
Which source of glucose is used preferentially by exercising muscle?
from muscle glycogenolysis
21. A function of the frontal lobe of the brain is a. auditory input and its interpretation b. general sensory input and its interpretation c. general intellect and motor control d. visual input and its interpretation
general intellect and motor control
fatigue
general sensations of tiredness and accompanying decrement in muscular performance; inability to maintain required power output to continue muscular work at a given intensity
53. What hormone is released from the pancreas at a higher rate during exercise to mobilize liver glucose and adipose tissue fatty acids? a. glucagon b. somatostatin c. insulin d. None of these is correct.
glucagon
during exercise, the four most important hormones for increasing plasma glucose concentrations are _____, _____, _____, and _____.
glucagon, epinephrine, norepinephrine, cortisol
9. The making of new glucose from a noncarbohydrate source is a. glycolysis b. glycogenolysis c. glycogenesis d. gluconeogenesis
gluconeogenesis
48. Which of the following is not a classification of hormone secreted by the adrenal cortex? a. glucocorticoids b. glycocorticoids c. mineralocorticoids d. gonadocorticoids
glycocorticoids
3. Metabolism a. is the creation of energy to build tissues in the body b. is the breakdown of food so that energy is available to do work c. is the sum of all energy transformations (chemical reactions) in the body d. does not follow the first law of thermodynamics, which states that energy is neither created nor destroyed, but only changed in form
glycogen
The fuel source most likely to limit endurance is _____.
glycogen
Why do plasma glucose concentrations start to decline after prolonged endurance exercise?
glycogen stores are depleted
22. The process by which glycogen is synthesized from glucose is called a. gluconeogenesis b. glycogenolysis c. glycolysis d. glycogenesis
glycogenesis
31. The synthesis of glycogen from glucose is called a. glycolysis b. gluconeogenesis c. glycogenolysis d. glycogenesis
glycogenesis
The process of breaking down glycogen into glucose is called ____, while the process of synthesizing new glucose from other substrates is called _____.
glycogenolysis, gluconeogensis
10. A localized change in a neuron's membrane potential, which may or may not spread over the entire cell membrane, is called a. graded potential b. action potential c. threshold potential d. hyperpolarization
grader potential
39. Type I fibers a. have a high anaerobic capacity b. have a low number of mitochondria c. have high aerobic endurance d. are capable of generating more force than type II fibers
have high aerobic endurance
Cardiac muscles are found only in the ____.
heart
Which of these is a consequence of low plasma volume?
heart strain increases
Static (isometric) contractions are unchanged, so lifting an object ____ than than the force generated by the muscle.
heavier
57. When electrolytes become concentrated in the blood plasma due to sweating, this is called a. hemodilution b. hemoconcentration c. hemophilia d. hemolytic
hemoconcentration
What 4 things make a successful endurance athlete
high VO2 max, high LT, many Type I mm fibers, Movement economy
peak oxygen uptake (VO2peak)
highest oxygen uptake achieved
Hormones maintain the balance and ______ of the body.
homeostasis
The hypothalamus is responsible to maintain _____ by regulating almost all processes that affect the body's ____ environment.
homeostasis, internal
insulin
hormone from pancreas that facilitates glucose transport into the cells, especially muscle fibers; promotes glycogenesis (generation of glycogen), and inhibits gluconeogenesis (generation of glucose)
erythropoietin (EPO) -
hormone released by kidneys that regulates red blood cell production by stimulating bone marrow cells. extremely important in our adaptation to training and altitude. most athletes involved in heavy training have an expanded plasma volume.
aldosterone
hormone released from adrenal cortex that works primarily by promoting renal reabsorption of sodium, thus causing the body to retain sodium. when Na+ is retained, so is water, but enhances excretion of K+ -so, like ADH, it results in water retention -also plays role in potassium balance as well -secretion stimulated by many factors: --decreased plasma sodium --decreased blood volume --decreased blood pressure --increased plasma potassium concentration
antidiuretic hormone (ADH)
hormone that promotes water conservation by increasing water reabsorption by the kidneys. as a result, less water secreted in urine, creating an antidiuresis and avoiding severe dehydration. -released when plasma osmolality is increased -released when low plasma volume is sensed by baroreceptors in the cardiovasuclar system.
_____ are chemicals that control and regulate the activity of certain cells or organs.
hormones
adipokines
hormones that are released by, or act on, fat tissue
NAD and FAD transfer ____ electrons to the electron transport chain.
hydrogen
49. Elevated plasma glucose is a. hyperglycemia b. hypoglycemia c. hyperthermia d. hyperglucocordemia
hyperglycemia
When plasma glucose concentrations are low (also called ___), ____ is secreted by the pancreas to promote glycogenolysis.
hypoglycemia, glucagon
The anterior pituitary is controlled by ___.
hypothalamic hormones
the posterior pituitary is controlled by ___.
hypothalamic nerve signals
kilocalories
in humans, energy is expressed in __. where 1 kcal = 1000 cal = 1 Calorie (dietary)
How does heat alter metabolic rate
inc rate of carb utilization, quickly depletes glycogen, high mm temp may impair mm fx, (51 degrees is best, 87 degrees is worst)
During exercise, glucagon concentrations ____, and insulin concentrations ____.
increase, decrease
67. The initial increase in heart rate up to about 100 bpm is mediated by decreases or withdrawal of vagal tone, further increases in heart rate are mediated by
increases in stimulation of sympathetic nervous system.
As the force production/power _____, the type of motor ____ goes from Type __ to Type II.
increases, units, I
T3 and T4 are responsible for ____.
increasing size and number of mitochondria, increasing cellular metabolic rate, and increasing FFA mobilization
Why is VO2 max generally expressed relative to body wt in ml of O2 consumed per kg of body wt per min for weight bearing activity
individual's energy expenditure vary with body size
T3 and T4 are responsible for all of the following except?
inhibiting protein synthesis
calorimeter
insulated, air-tight chamber that contain copper tubing throught which water is circulated. Heat produced by the body radiates to the walls and heats the water
54. Transport of glucose through the cell membrane and into the muscle cell is controlled by a. glucagon b. insulin c. epinephrine d. cortisol
insulin
Glucose mobilization is stimulated by glucagon, and glucose uptake by cells is stimulated by ____. Though these seem like opposite effects, both are essential during exercise.
insulin
Which of the following paris of hormones typically act in opposition?
insulin, glucagon
____ and ____are secreted by the pancreas and play an important role in regulating plasma glucose concentration.
insulin, glucagon
The frontal lobe is responsible for general _____ and _____ control.
intellect, motor
chronic adaptation
is 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. ex: cardiovascular, and skeletomuscular system -cardiovascular system adapts based on amount of activity
acute exercise
is a single bout of exercise
3. Metabolism a. is the creation of energy to build tissues in the body b. is the breakdown of food so that energy is available to do work c. is the sum of all energy transformations (chemical reactions) in the body d. does not follow the first law of thermodynamics, which states that energy is neither created nor destroyed, but only changed in form
is the sum of all energy transformations (chemical reactions) in the body
13. Saltatory conduction a. is when an action potential appears to jump from one node to the next as it traverses a unmyelinated fiber b. is when an action potential appears to jump from one node to the next as it traverses a myelinated fiber c. can occur in both myelinated and unmyelinated fibers d. None of these is correct.
is when an action potential appears to jump from one node to the next as it traverse myelinated fiber
28. Which of the following statements is not an accurate description of anaerobic glycolysis? a. It takes place in the cytoplasm of the cell. b. It generates large amounts of ATP. c. It produces lactic acid. d. It is an important source of energy during high-intensity exercise that is sustained for 1 to 2 minutes.
it generates large amounts of ATP
as mm glycogen dec. what happens to liver glycogenesis
it increases
26. Which of the following is a true statement concerning the region of the brain called the diencephalon? a. It is made up of the midbrain, the pons, and the medulla oblongata b. It regulates what sensory input reaches the conscious brain and thus is very important for motor control. c. It is primarily responsible for conscious thought and voluntary control of movement. d. It is the site of the major autonomic regulatory centers that control the respiratory and cardiovascular systems.
it regulates what sensory input reaches the conscious brain and thus is very important for motor control
Why may lactic acid be beneficial if production=clearance (not fatiguing) (4)
it serves as a source of fuel: directly oxidized by type I fiber mitochondria, shuttled from type II fibers to type I for oxidaton, converted to glucose via gluconeogenesis in the liver
ADH stimulates water retention at its target cells in this organ: ____.
kidney
Renin is released when the ____.
kidneys sense low blood volume and pressure
20. The major metabolic waste product that causes the muscles and blood to have a lower pH during exercise of increasing intensity is a. bicarbonate b. nitrogen c. carbon dioxide d. lactate
lactate
19. Anaerobic glycolysis begins with either glucose or glycogen and ends with a. pyruvate b. lactic acid c. acetyl CoA d. the electron transport chain
lactic acid
titin
large protein that has elastic properties, stabilizes myosin equally spaces out actin. filaments extend from the Z-disk to the M-line
Eccentric contractions are the _____ of a muscle (i.e. lowering biceps of a heavy weight)
lengthening
O2 consumed in early exercise is (greater/less) than O2 demand...This means
less- Therefore, this occurs when anaerobic pathways are used for ATP production. The body incurs an O2 deficit fround by taking the O2 required-the O2 consumed. O2 needs and O2 supply differ.
A key characteristic of steroid hormones is _____.
lipid soluble
39. The process by which triglycerides are broken down into glycerol and free fatty acids is called a. lipogenesis b. lipolysis c. hydrolysis d. beta oxidation
lipolysis
The breakdown of triglycerides into FFAs, a process called ____, is stimulated by the enzyme _____, which is under hormonal control.
lipolysis, lipase
An example of a target cell for glucagon would be ____.
liver cells
64. During exercise, the Frank-Starling mechanism appears to have its greatest influence at ____ exercise intensities and contractility has its greatest effects at ____ exercise intensities.
low, high
The more fats, means what for the RER and energy
lower RER and lower energy
7. Which of the following is incorrect concerning the sarcolemma or plasmalemma? a. helps to maintain acid-base balance b. assists in the transmission of the action potential from the motor neuron to the muscle fiber c. major site of energy production d. transports metabolites from the capillary blood into the muscle fiber
major site of energy production
12. Large amounts of one particular fuel can cause cells to rely more on that source than on alternatives is best called a. catabolism b. lipogenesis c. mass action effect d. bioenergetics
mass action effect
maximal oxygen uptake (VO2max)
maximal limit of one's ability to increase VO2 (aerobic capacity) * Normally active untrained college-aged students = 38-42 ml/kg/min
endomysium
meaning within the muscle, is a wispy layer of areolar connective tissue that ensheaths each individual myocyte (muscle fiber, or muscle cell). It also contains capillaries and nerves. It overlies the muscle fiber's cell membrane
direct calorimetry
measuring body's heat production to gauge the rate and quantity of energy production; uses a calorimeter
Mechanoreceptors respond to _____ forces such as ______, _____, _____, or _____.
mechanical, pressure, touch, vibrations, stretch
49. Intrinsic control of blood flow may be accomplished through
metabolic regulation, endothelial-mediated vasodilation, and myogenic contraction. (see google doc. for more detail...lots more detail)
Norepinephrine concentrations increase at _____ exercise intensities, and epinephrine concentrations increase at ____ exercise intensities.
moderate, high
gross motor control
more fibers per motor unit -like large muscles in the legs
insulin sensitivity
more insulin receptors on the cell membrane than normal so the body has to produce less insulin to maintain a normal plasma glucose level.
10. The human body contains _______________ skeletal muscles. a. approximately 200 b. approximately 400 c. more than 600 d. more than 1,000
more than 600
low muscle pH
most researchers agree that __ is the major limiter of performance and the primary cause of fatigue during maximal, all-out exercise lasting more than 20 to 30 seconds.
The thalamus regulates what sensory input reaches the conscious brain and thus is very important for ____ ____.
motor control
21. A single motor nerve and all of the muscle fibers that it supplies are referred to as a a. synapse b. motor unit c. motor junction d. motor end plate
motor unit
44. During a progressive increase in exercise intensity, which of the following is true concerning motor unit recruitment? a. Fast-twitch motor units are recruited first. b. Motor units with small motor neurons are recruited first. c. Motor units with large motor neurons are recruited first. d. Motor units are recruited in random order.
motor units with small motor neurons are recruited first
A motor unit is composed of a single _____ neuron all of the _____ it innervates
motor, fibers
A motor unit is the single ____ neuron and all the muscle ____ it innervates.
motor, fibers
Resting metabolic rate
much like BMR but does not require stringent standardized conditions
type I; slow; type II; fast
muscle fiber types: -__: --50% of fibers in average muscle --peak tension in 110ms (__ twitch) -__: --type IIa: 25% of fibers in average muscle --type IIx: 25% of fibers in average muscle --peak tension in 50ms (fast twitch)
delayed-onset muscle soreness (DOMS)
muscle soreness that develops a day or two after a heavy bout of exercise and that is associated with actual injury within the muscle -vary from slight muscle stiffness to severe, debilitating pain that restricts movement -almost all current theories acknowledge that eccentric muscle action is the primary initiator of DOMS -pathway for developing this beings with structural damage to muscle fibers and to the surrounding connective tissues -causes reduction in the force-generating capacity of the affected muscles. -failure in excitation-contraction coupling appears to be the most important, in first 5 days.
41. When performing a volleyball spike, the athlete's arm is rapidly stretched just before the spike. Which of the following structures detects and responds to that stretch by reflexively increasing muscle activity? a. muscle spindle b. Golgi tendon *c. extrafusal fibers d. pacinian corpuscle
muscle spindle
Role of genetics in determining proportions of muscle fiber types: The distribution of ____ fiber types in an individual is determined primary by ____ make-up. We are predisposed to having more ____-twitch than ____- twitch. The percentage of our muscle fiber types is not a reliable prediction of our success in a specific sport.
muscle, genetic, fast, slow
14. What structure is attacked with certain neurological diseases such as multiple sclerosis? a. cell body b. dendrites c. myelin sheath d. nodes of Ranvier
myelin sheath
24. The fatty covering found on some axons is referred to as the a. myelin sheath b. neurilemma c. soma d. nodes of Ranvier
myelin sheath
25. The speed of a neural impulse is dependent on a. dendrite accuracy and axon diameter b. myelinization and axon diameter c. myelinization and somatic pressure d. somatic pressure and myelin thickness
myelinization and axon diameter
The sarcoplasmic reticulum surrounds ______ which create an elaborate network of _____ channels anchored at a T- _____
myofibrils, calcium, tubule
57. Myoglobin found in skeletal muscle serves to transport O2 in the muscle to the mitochondria to be used in oxidative metabolism;
myoglobin has a much greater affinity for O2 than hemoglobin
20. The thick filaments of a myofibril are composed mainly of a. sarcoplasm b. tropomyosin c. actin d. myosin
myosin
Sliding filament theory and how muscle fibers shorten: With calcium activation, ____ head binds to actin. ____ head tilts toward the arm of the ____- ____ and drags actin toward center of _____. The pulling of the _____ filament past the myosin filament results in ______ of the sarcomere and generates muscle force/organized muscle contraction.
myosin, myosin, cross-bridge, sarcomere, actin, shortenting
two; actin
myosin: -__ intertwined filaments, so two globular heads -each globular head protrude 360 degrees from thick filament axis, and will interact with __ filaments for contraction -stabilized by titin
The inside of the cell is _____ relative to the outside.
negative
Neuron bundles in the peripheral nervous system are referred to as ______.
nerve
cholinergic
nerves that primarily release acetylcholine
adrenergic
nerves that primarily release norepinephrine
66. Motor neurons communicate with muscles at sites known as _____ junctions.
neuromuscular
18. The site of impulse conduction from a neuron to a muscle fiber is called a a. synapse b. neuromuscular junction c. synaptic junction d. sarcolemma
neuromuscular junction
3. The basic structural element of the nervous system is the a. axon b. dendrite c. cell body d. neuron
neuron
dendrites are the _____ receivers.
neurons
15. Which of the following is incorrect? a. The velocity of nerve impulse transmission is also determined by the neuron's size. b. Neurons of small diameter conduct nerve impulses faster than neurons of larger diameter. c. Neurons communicate with each other across synapses. d. Only when the sum of all individual action potentials meets or exceeds threshold can a graded potential occur.
neurons of small diameter conduct nerve impulses faster than neurons of larger diamter
motor neuron
neurons that project their axons outside the CNS to directly or indirectly control muscles -may determine fiber type
norepinephrine
neurotransmitter for most sympathetic autonomic neurons, and can be either excitatory or inhibitory, depending on the receptors involved.
19. Synaptic knobs house numerous vesicles, or sacs, filled with chemicals known as a. neurotransmitters b. neural substance agents c. synaptotransmitters d. axon terminals
neurotransmitters
How is economy of effort measured and what is its relationship to sport performance?
no way to measure economy; high economy of effort mean using less energy during activity and therefore being able to exercise for longer periods of time
16. Two major neurotransmitters involved in regulating our physiological responses to exercise are a. norepinephrine and acetylcholine b. dopamine and carnitine c. adenosine and serotonin d. histamine and calcitonin
norepinephrine and acetylcholine
The cell body contains the _____.
nucleus
For a given plasma concentration, hormone effectiveness can be altered by the ____.
number of cell receptors
hyperpolarization
occurs any time the charge difference becomes more negative than the RMP of -70mV, moving to a larger negative value -more K+ channels open, K+ leaves the cell -makes more difficult for nerve impulse to reach action potential.
depolarization
occurs any time the charge difference becomes more positive than the RMP of -70mV, moving closer to zero. -typically results from a change in the membrane's Na+ permeability
27. The active binding sites to which myosin cross-bridges attach during muscle contraction are found a. on the myosin filaments b. on the actin filaments c. on the Z-discs d. on the thick filaments
on the actin filaments
degraded; presynaptic terminals; diffuses
once the neurotransmitter binds to the postsynaptic receptor, the nerve impulse has been successfully transmitted. the neurotransmitter then: 1) is __ by enzymes 2) is actively transported back in the the __ for reuse 3) __ away from the synapse
Osmotic flow of water between fluid compartments depends on the ____ pressure in tissues and the ____ pressure in the blood vessels.
osmotic, hydrostatic
What role does oxygen play in the process of aerobic metabolism? Aerobic metabolism relies on ____ to working muscles before in can create ____, therefore, _____ is a direct energy source.
oxygen, ATP, oxygen
Lactic acid is used in the absence of _____. It can _____ the fiber's calcium-binding capacity and may impede muscle ______. The liver can turn it into ____ acid and a hydrogen ion, which can be used as energy.
oxygen, decrease, contraction, pyruvic
What helps defer PCr depletion?lookup
pacing
Nociceptors respond to _____ stimuli.
painful
37. Nociceptors are sensory receptors that respond to a. temperature changes b. pressure and touch c. painful stimuli d. light
painful stimuli
29. Constriction of bronchial airways is elicited by
parasympathetic stimulation.
sarcolemma
part of a myofibril that is composed of the plasmalemma and the basement membrane
LT is usually expressed as
percentage of VO2 max, since ppl have different VO2 max...LT affects the percentage of VO2 max that an athlete can maintain for a prolonged period. Therefore a higher LT=higher sustained exercise intensity
10. The process of converting ADP to ATP by the addition of a phosphate group is called a. hydrolysis b. aerobic metabolism c. phosphorylation d. anaerobic metabolism
phosphorylation
43. The ____ can be thought of as the relay between central nervous system control centers and peripheral endocrine glands. a. thyroid gland b. pituitary gland c. adrenal gland d. pancreas
pituitary gland
cell's sensitivity
plasma insulin concentration tends to decrease during prolonged exercise, despite a slight increase in plasma glucose concentration and glucose uptake by muscle. this is a reminder that a hormone's activity is determined not only by its concentration in the blood but also by a __ to that hormone.
The progressive loss of fluid from plasma during exercise leads to an increase in ____, which stimulates the release of ADH.
plasma osmolality
VO2 max definition
point at which O2 consumption doesn't increase with further increase in intensity...best measure of aerobic fitness but not the best predictor of endurance performance
Lactate threshold definition
point at which blood lactate accumulation is increased dramatically.
When the charges across the membrane differ, the membrane is said to be _____.
polarized
44. The ___ has a major role in fluid and electrolyte balance. a. posterior pituitary gland b. thyroid gland c. anterior pituitary gland d. adrenal gland
posterior pituitary gland
The neuron has a high concentration of _____ ions on the inside of the membrane and a high concentration of _____ ions on the outside.
potassium, sodium
The tilt of the myosin head is known as the ____-____
power-stroke
Acetylcholine
primary neurotransmitter for motor neurons that innervate skeletal muscles as well as for most parasympathetic autonomic neurons. -generally an excitatory neurotransmitter in somatic nervous system but can have inhibitory effects at some parasympathetic nerve endings, such as in the heart
gluconeogenesis
process by which protein or fat is converted into glucose
lipolysis
process of breaking down triglyceride to its basic units to be used for energy
lipogenesis
process of converting protein into fatty acids -for energy storage -for cellular energy substrate
11. Protein can supply about 5 to 10% of the total energy needs during a. sprinting activities b. prolonged exercise c. all types of exercise d. weightlifting
prolonged exercise
50. Which of the following is not a function of insulin? a. facilitates glucose transport into the cells, especially those in muscle b. promotes glycogenesis c. promotes glycogenolysis d. inhibits gluconeogenesis
promotes glycogenesis
45. Growth hormone a. is a potent catabolic agent b. promotes muscle growth and hypertrophy c. facilitates lipogenesis d. stimulates carbohydrate metabolism
promotes muscle growth and hypertrophy
Hormone secretion is ____.
pulsatile
Neurons within the precentral gyrus of the frontal lobe, known as _____ cells, are responsible for the conscious control of skeletal muscle movements.
pyramidal
In myelinated nerve fibers, the action potential appears to jump from one node of ____ to another.
ranvier
49. ___ is the term used to describe the process by which the tension of a given motor unit can vary from that of a twitch to that of tetanus by increasing the frequency of stimulation of that motor unit. a. summation b. rate coding c. size principle d. all-or-none principle
rate coding
basal metabolic rate
rate of energy expenditure for an individual in supine position, measured in a thermoneutral environment immediately after 8 hours of sleep and at least 12 hours of fasting Average range: 1200 - 2400 kcal/day
Basal metabolic rate definition
rate of energy expenditure measured in a supine position in a thermo-neutral environment immediately after 8h of sleep and 12h of fasting
respiratory exchange ratio
ratio between rate of CO2 release (VCO2) and oxygen consumption (VO2) RER= VCO2/VO2; at rest=0.78 -0.8
What is the respiratory exchange ratio
ratio between rates of CO2 production and O2 usage
33. The so-called slow component of oxygen-uptake kinetics observed during exercise at power outputs above the lactate threshold is probably most closely related to
recruitment of a higher percentage of fast-twitch muscle fibers which are less efficient (the require a higher VO2 to achieve the same power output) Page 106
Erythropoietin release is the primary stimulus for ____.
red blood cell production
osmolality
refers to the ionic concentration of dissolved substances in the plasma. -increasing this triggers ADH to be released and retain water to dilute plasma electrolyte concentration back to normal levels
60. The kidneys respond to decreased blood pressure or blood flow by forming an enzyme and hormone called a. antidiuretic hormone b. renin c. aldosterone d. epinephrine
renin
Renin release is the first step in a series of cascading reactions, collectively termed the ______________.
renin-angiotensin-aldosterone mechanism
20. The kidneys respond to decreased blood pressure or blood flow by forming an enzyme and hormone called
renin.
gamma motor neurons
responsible for keeping the ends of intrafusal fibers taught during shortening of the extrafusal fibers -these neurons and alpha motor neurons send their signals at the same time to allow the actions to simultaneously occur
7. The electrical charge difference between the negative charged particles on the inside of the cell with respect to the positive charge on the outside of the cell is called a. resting membrane potential b. conductivity c. action potential d. sensitivity
resting membrane potential
17. The smallest functional unit of a muscle is the a. myofilament b. sarcomere c. Z-disc d. motor unit
sarcomere
64. The _____is the smallest functional unit of a muscle.
sarcomere
Myofibrils are divided into ______, which are the ______ unit of the skeletal muscle
sarcomeres, contractile
striations; A-bands; I-bands; H-zone; M-line; Z-disk
sarcomeres: -distinctive striped appearance (__) --__: dark stripes --__: light stripes --__: middle of an A-band. only visible when myofibril is relaxed. --__: middle of H-zone --common boundary structure: __.
12. Which structure within skeletal muscle stores and releases calcium? a. T-tubules b. sarcoplasmic reticulum c. sarcolemma d. nucleus
sarcoplasmic reticulum
13. Calcium ions, responsible for turning on muscle contraction, are stored in the a. sarcolemma b. T-tubules c. cross-bridges d. sarcoplasmic reticulum
sarcoplasmic reticulum
14. The specialized network of membranous tubules that stores calcium ions in a muscle fiber is the a. sarcolemma b. mitochondria c. sarcoplasmic reticulum d. motor unit
sarcoplasmic reticulum
Nonsteroid hormones use these intracellular chemicals to help bring about their intended effects: _____.
second messengers
glucagon
secreted when the plasma glucose concentration falls below normal concentrations (hypoglycemia). -promotes increased breakdown of liver glycogen to glucose (glycogenolysis) and increased gluconeogenesis (generation of glucose), both of which increase plasma glucose levels
The parietal lobe is responsible for general ____ input and interpretation.
sensory
The thalamus is an important ______ integration center.
sensory
43. Which of the following is the proper sequence of events during sensory-motor integration? a. sensory reception, CNS processing and response selection, motor impulse transmission, motor response, sensory transmission b. motor response, motor impulse transmission, CNS processing and response selection, sensory transmission, sensory reception c. motor impulse transmission, motor response, CNS processing and response selection, sensory reception, sensory transmission d. sensory reception, sensory transmission, CNS processing and response selection, motor impulse transmission, motor response
sensory reception, CNS processing and response selection, motor impulse transmission, motor response, sensory transmission
golgi tendon organs
sensory receptor embedded in tendon -sensitive to tension (strain gauge) -if too much tension, sends message causing inhibition of agonists, excite antagonists. -reduce potential for injury
Concentric contractions are the ____ of a muscle (i.e. raising a weight)
shortening
How many hormones does the anterior pituitary secrete?
six
glucose
six carbon sugar that is the primary form of carbohydrate used for metabolism
3. Which of the following is also referred to as voluntary muscle? a. skeletal muscle b. smooth muscle c. visceral muscle d. cardiac muscle
skeletal muscle
39. Which of the following is not directly regulated by the autonomic nervous system? a. skeletal muscle contraction b. heart rate c. respiration d. blood pressure
skeletal muscle contraction
Type I muscle fibers are ____-twitch fibers, oxidative, recruited during __- intensity endurance events. They produce ATP from oxidation of ____ and fats. Used during high anaerobic/aerobic endurance. (pick which one is correct)
slow, low, carbs, aerobic
While both the nervous and endocrine systems are critical for communication and coordination among body systems, the endocrine system responds more ____.
slowly but has longer-lasting effects.
The thalamus detects all sensory input, except ____, which enters the thalamus and is relayed to the appropriate area o the _____.
smell, cortex
2. Muscles that constrict or dilate to control blood flow are called a. skeletal muscle b. voluntary muscle c. smooth muscle d. cardiac muscle e. visceral muscles
smooth muscle
4. The type of muscle that is found in the walls of most internal organs is a. skeletal muscle b. smooth muscle c. voluntary muscle d. cardiac muscle
smooth muscle
acute muscle soreness
soreness or pain felt during and immediately after an exercise bout -classified as a muscle strain and is perceived as muscle stiffness, aching, or tenderness -can result from accumulation of the end products of exercise, such as H+ and from tissue edema -usually disappear within a few minutes to several hours after the exercise
51. Isometric muscle contraction is a. dynamic b. static
static
16. The process of direct gene activation occurs with a
steroid hormone. The hormone binds to its specific receptor. The receptor-hormone complex enters the nucleus and binds to the cell's DNA, thus activating genes.
35. The process of direct gene activation occurs with a. steroid hormones b. nonsteroid hormones c. protein-based hormones d. None of these is correct.
steroid hormones
Conscious aspects of fiber recruitment
stress of exhaustive exercise may be too much, subconscious or conscious unwillingness to endure more pn, warning signs from discomfort of fatigue, elite athletes learn how to properly pace to tolerate fatigue
sarcoplasmic reticulum (SR)
structure of muscle fibers: -Ca2+ storage -parallel the myofibrils and loop around them
sarcomeres
structure of muscle fibers: -basic contractile element of skeletal muscle -end to end for full myofibril length -joined at the Z-disks
transverse tubules (T-tubules)
structure of muscle fibers: -extensions of plasmaloemma in the sarcoplasm that passes through the muscle fiber -carry AP deep into muscle fiber -enables pathways from outside fiber to its interior, enabling substances to enter the cell and waste to leave the fibers
sarcoplasm
structure of muscle fibers: -located between the plasmalemma and the basement membrane -cytoplasm of muscle cell -unique features (from normal cytoplasm): glycogen storage, myoglobin
myofibrils
structure of muscle fibers: -muscle-> fasciculi -> muscle fiber -> __. -hundreds to thousands per muscle fiber -made up of sarcomeres
satellite cells
structure of muscle fibers: -skeletal muscle growth, development -adaptation response to injury, immobilization, training
plasmalemma (cell membrane)
structure of muscle fibers: -fuses with tendon -conducts action potential from motor neuron to muscle fiber -maintains pH, transports nutrients from capillary blood to muscle fiber -appears as a series of shallow folds along surface of fiber when fiber contracted, but folds disappear when the fiber is stretched.
40. The two enzymes most commonly measured in order to assess the oxidative capacity of muscle tissue are a. succinate dehydrogenase and citrate synthase b. phosphofructokinase and lactate dehydrogenase c. nicotinamide adenine dinucleotide and flavin adenine dinucleotide d. ATPase and creatine kinase
succinate dehydrogenase and citrate synthase
muscle fiber
surrounded by endomysium consists of myofibrils divided into sarcomeres
fasciculi
surrounded by perimysium consists of individual muscle cells (muscle fibers)
44. An increase in heart rate that occurs before competition is due to (which nervous sys)
sympathetic
33. The autonomic nervous system can be divided into two functional and anatomical divisions called a. sympathetic and unsympathetic b. sympathetic and parasympathetic c. afferent and efferent d. CNS and peripheral
sympathetic and parasympathetic
40. Which division of the autonomic nervous system is important for an athlete preparing for competition? a. parasympathetic because it slows heart rate to prevent nervousness b. sympathetic because it increases heart rate and strength of heart contraction c. parasympathetic because it causes bronchoconstriction d. sympathetic because metabolic rate decreases to conserve calories needed for exercise
sympathetic because metabolic rate decreases to conserve calories needed for exercise
42. The division of the nervous system that is often referred to as the fight-or-flight system is the a. peripheral nervous system b. sympathetic nervous system c. somatic nervous system d. autonomic nervous system e. parasympathetic nervous system
sympathetic nervous system
5. The site of impulse conduction from one neuron to another is called a(n) a. dendrite b. axon c. neuromuscular junction d. synapse
synapse
A nerve impulse traveling from a motor neuron to a specific muscle fiber must cross the _____.
synapse
A(n) ____ is the site of impulse transmission from one neuron to another.
synapse
At a neuromuscular junction, the space between the axon terminal and the motor endplate is called the ______ cleft.
synaptic
Cells that express a receptor for a given hormone and can therefore be affected by that hormone are referred to as _____.
target cells
15. While hormones circulate to all tissues, some affect only a few tissues. This is due to
target cells, specific hormone receptors, lock and key.
Thermoreceptors respond to changes in _____.
temperature
25. All-out maximal exercise of 6 seconds in duration would stress a. the ATP-PCr system b. the glycolytic system c. the oxidative system d. all three systems equally
the ATP-PCr system
synaptic knobs
the __ at the tips of the end branches are filled with vesicles containing neurotransmitters
26. The primary mechanism responsible for maintaining the resting membrane potential of a neuron is
the active pumping of sodium and potassium ions across the neuronal membrane by the sodium-potassium pump.
phosphorylation
the addition of a phosphate group (PO4) to a molecule
38. When a muscle fiber is stimulated by a motor nerve, the muscle fiber either will contract maximally or it will not contract at all. This is referred to as a. the sliding filament theory of contraction b. the all-or-none principle c. muscle fiber recruitment order d. the size principle
the all-or-none principle
33. Which of the following is not true of fast-twitch fibers? a. Generally there are 3 types of FT fibers (IIa, IIx, IIc). b. FT fibers have a more highly developed sarcoplasmic reticulum. c. The alpha-motor neuron in a FT fiber has a smaller cell body and typically innervates a cluster of < 300 muscle fibers. d. FT fibers are fast to contract and fast to fatigue.
the alpha-motor neuron in a FT fiber has a smaller cell body and typically innervate cluster of <300 fibers
sport physiology
the application of the concepts of exercise physiology to train ing athletes and enhancing sport performance
8. The striated appearance of skeletal muscle fiber is mainly due to a. variations in the thickness of the sarcolemma b. the arrangement of the actin and myosin myofilaments c. the T-tubules d. the intracellular myoglobin
the arrangement of the actin and myosin myofilaments
metabolic flexibility
the body's ability to adapt substrate oxidation to changing fuel availability and energy demands
resting metabolic rate
the bodys metabolic rate early in the morning following 8 hours of sleep average total RMR of an individual engaged in normal daily activity = 1800-3000
2. The central nervous system is composed of a. the brain and spinal cord b. an afferent division c. an efferent division d. the autonomic nervous system and the somatic nervous system
the brain and spinal cord
glycolysis
the breakdown of glucose to pyruvic acid
1. The two main components of the nervous system are a. the autonomic nervous system and the somatic nervous system b. the brain and the spinal cord c. the central nervous system and the peripheral nervous system d. the efferent and afferent divisions of the nervous system
the central nervous system and the peripheral nervous system
acetyl coenzyme A (acetyl CoA)
the compound that forms the common entry point into the krebs cycle for the oxidation of carbohydrate and fat
perimysium
the connective tissue sheath surrounding each fascicle.
50. The distribution of blood to various tissue areas is controlled mainly by
the constriction and dilation of vessels
glycogenolysis
the conversion of glycogen to glucose
20. The portion of the brain that allows the two hemispheres of the cerebrum to communicate with each other is called a. the brain stem b. the corpus callosum c. the cerebral cortex d. arachnoid
the corpus callosum
12. The membrane voltage at which a graded potential becomes an action potential is called a. the depolarization threshold b. the repolarization threshold c. the refractory threshold d. the propagation threshold
the depolarization threshold
creatine kinase
the enzyme that facilitates the breakdown of PCr to creatine and Pi in the ATP-PCr System -controls rate of ATP production --negative feedback system --when ATP levels drop (ADP levels rise), CK activity increases --when ATP levels increase, CK activity decreases
glycogen
the form of carbohydrate stored in the body, found predominantly in the muscles and liver
pyruvic acid
the glycolytic system starts with glucose-6-phosphate, and ends with __: -10 to 12 enzymatic reactions total for breakdown of glycogen to pyruvic acid, which is then converted to lactic acid -all steps occur in cytoplasm -ATP yield: 2 ATP for glucose, 3 ATP for glycogen
22. When an excitatory neural impulse from one neuron is transmitted to a second neuron, a. an IPSP is generated on the membrane of the second neuron b. the impulse causes a hyperpolarization of the second neuron c. the impulse causes depolarization of the second neuron d. the impulse can cause either hyperpolarization or depolarization of the second neuron
the impulse causes depolarization of the second neuron
40. Which of the following is not a true statement? a. The leg muscles of an elite sprinter would be expected to have a higher percentage of fast-twitch muscle fibers than the leg muscles of the average person. b. The leg muscles of an elite distance runner would be expected to have a higher percentage of slow-twitch fibers than the leg muscles of an average person. c. Muscle fiber distribution in the body is determined primarily by genetics. d. The likelihood of a person's future athletic success in a particular sport can be reliably predicted by analysis of the person's fiber type distribution.
the likelihood of a person's future athletic success in a particular sport can be reliably predicted by analysis of the person's fiber type distribution
basal metabolic rate (BMR)
the lowest rate of body metabolism (energy use) that can sustain life, measured after an overnight sleep in a lab under optimal conditions of quiet, rest, and relaxation and after a 12 hour fast
homeostasis
the maintenance of constant internal environment. ex: low glucose, atpa muscle contcentration, blood pressure, body temperature, blood flow -all need to be maintained under normal physiological conditions for organs to function properly
29. The brain stem is composed of a. the cerebellum, the thalamus, and the corpus callosum b. the midbrain, the thalamus, and the corpus callosum c. the pons, the medulla oblongata, and the cerebellum d. the midbrain, the pons, and the medulla oblongata
the midbrain, the pons, and the medulla oblongata
excess postexercise oxygen consumption (EPOC); lactate threshold
the most common methods for estimating anaerobic contribution to sustained exercise involve examination of either the __ or the __.
46. An eccentric muscle contraction is one in which a. the muscle lengthens as contractile force is generated b. the muscle shortens as contractile force is generated c. the muscle produces contractile tension but joint angle does not change d. the muscle shortens but no contractile tension is generated
the muscle lengthens as contractile force is generated
42. Which of the following is not true? a. Training may alter the metabolic capabilities of muscle fibers (between IIa and IIx). b. Order of recruitment of motor units is directly related to their motor neuron size. c. Motor units with smaller motor neurons will be recruited first. d. The nervous system tends to recruit those muscle fibers best adapted to the activity; therefore, type IIa and IIx fibers are primarily recruited during a marathon.
the nervous system tends to recruit those muscle fibers best adapted to the activity, therefore, type IIa and IIx fibers are primarily recruited during a marathon
28. Acetylcholine (ACh) is a. one of the major waste products generated by muscle contraction b. the neurotransmitter that is released by motor nerves c. the chemical energy source for muscle contraction d. the enzyme that catalyzes the splitting of ATP in a muscle fiber
the neurotransmitter that is released by motor nerves
Why are the ATP-PCr and glycolytic energy systems considered anaerobic?
the occur without the use of oxygen
size principle
the order of recruitment of motor units directly related to size of alpha motor neuron
enzyme; fiber; availability
the oxidative capacity of muscle: -not all muscles exhibit maximal oxidative capabilities -factors that determine oxidative capacity: --__ activity --__ type composition, endurance training --O2 __ vs O2 need
23. The primary energy source during a marathon is a. the glycolytic system b. the ATP-PCr system c. the oxidative system d. glycolysis
the oxidative system
lactate threshold
the point at which blood lactate begins to substantially accumulate above resting concentrations during exercise of increasing intensity Normal levels 0.8-2.5 mmol/L
27. Beta oxidation is the name for a. the series of reactions by which glucose is converted to pyruvic acid in cell cytoplasm b. the series of reactions making up the electron transport chain c. the process by which free fatty acids are broken down to yield multiple molecules of acetyl CoA d. the process by which proteins are metabolized aerobically in the mitochondria
the process by which free fatty acids are broken down to yield multiple molecules of acetyl-CoA
Metabolic rate definition
the rate at which the body uses energy
29. Which of the following is incorrect? a. Fat provides more kcals of energy per gram than carbohydrate. b. Fat oxidation requires more oxygen than carbohydrate oxidation. c. A unique component of protein is nitrogen. d. The rate of lipolysis is controlled by ATPase.
the rate of lipolysis is controlled by ATPase
8. Which of the following statements is true concerning the cell membrane of a resting neuron? a. The membrane is more permeable to Na+ than to K+. b. The outside of the membrane is more negative than the inside c. The resting membrane potential of a typical neuron is about 70 mV. d. The sodium-potassium pump helps maintain the neuron's resting membrane potential by pumping K+ out of the cell and Na+ into the cell.
the sodium-potassium pump helps maintain the neuron's resting membrane potential by pumping K out of the cell and Na into the cell
exercise physiology
the study of how body structure and function are altered by exposure to acute and chronic bouts of exercise. studies different mechanisms on how body maintains homeostasis.
physiology
the study of how organisms function. study of the function of organisms
environmental physiology
the study of the effects of the environment on the function of the body. -changes in humidity, temperature, etc.
catabolism
the tearing down of body tissue; the destructive phase of metabolism
muscle spindle; golgi tendon organs
the two specific reflexes that help control muscle function
34. While hormones circulate to all tissues, some affect only a few tissues. This is due to a. the differences between hormones b. the fitness level of the individual c. the type of receptor at the tissue d. the concentration of the hormone
the type of receptor at the tissue
central governor theory
theory proposing that processes occur in the brain that regulate power output by the muscles to prevent unsafe levels of exertion. -brain regulates power output by the muscles to maintain homeostasis and prevent unsafe levels of exertion that may damage tissues or cause catastrophic events -limits exercise by decreasing the recruitment of muscle fibers, which in turn causes fatigue
The A-band is the dark zone containing ____ filaments, it stays constant during _____ and is made up of both ____ and ____.
thick, contraction, myosin, actin
Myosin and titin are the ______ filaments, where as actin, tropomyosin, troponin are the ______ filaments
thick, thin
The I-band is the light zone containing ____ filaments, it narrows during _____, and is only made up of ____.
thin, contraction, actin
muscle fiber (muscle cell)
this type of cell contains multiple nuclei that regulate protein synthesis and other processes within the cell.
Any depolarization that does not attain the ______ will not result in an ____ _____.
threshold, action potential
Any time depolarization reaches or exceeds the ____, an _____ _____ will result.
threshold, action potential
Anterior pituitary stimulation of the ___ gland via ___ leads to secretion of T3 and T4 (both potent hormones for increasing metabolic rate).
thyroid, TSH (thyrotropin)
15. Phosphocreatine is a high-energy phosphate compound that is used in the cell a. to resynthesize ATP b. to transport ATP to the mitochondria c. as a direct source of energy for the cell d. as a rate-limiting enzyme in the metabolism of fat and carbohydrate
to resynthesize ATP
56. Approximately 60-70% of the carbon dioxide transported in the blood is
transported as bicarbonate ion.
The ____ _____ are located in between 2 terminal cisternae, which provide a pathway for an action potential to signal the ____ _____ to release _____
transverse-tubules, sarcoplasmic reticulum, Ca 2+
24. Calcium ions, when released from the sarcoplasmic reticulum, interact with ________________ on the actin filaments. a. the sarcolemma b. cross-bridges c. troponin d. tropomyosin
troponin
6. Calcium ions, when released from the sarcoplasmic reticulum, interact with __ on the actin filaments.
troponin
47. The velocity of nerve impulse transmission in large myelinated fibers can be 5 to 50 times faster than in unmyelinated fibers of the same size a. true b. false
true
48. The sum of all changes in the membrane potential must equal or exceed the threshold. This summing of the individual impulses' effects is called summation. a. true b. false
true
49. Efferent impulses travel to the skeletal muscles. a. true b. false
true
51. Action potentials are not generated if threshold is not met. a. true b. false
true
52. An impulse received by one neuron from another neuron may be either excitatory or inhibitory. a. true b. false
true
52. Skeletal muscle is also referred to as voluntary muscle. a. true b. false
true
53. Muscle fibers in a specific motor unit are homogeneous with respect to fiber type. a. true b. false
true
53. Skeletal muscles are attached to bones via ligaments. a. true b. false
true
54. Axons conduct impulses away form the cell body. a. true b. false
true
55. Muscle cells are also referred to as muscle fibers. a. true b. false
true
56. The peripheral nervous system is composed primarily of cranial nerves and spinal nerves. a. true b. false
true
57. The autonomic nervous system controls the body's involuntary internal functions. a. true b. false
true
58. In the contraction of a muscle fiber, the tilting of the myosin head is referred to as the power stroke. a. true b. false
true
59. Muscle cells require energy for both the action and relaxation phases of contraction. a. true b. false
true
60. The primary motor cortex is responsible for the control of fine and discrete muscle movements. a. true b. false
true
61. Corticospinal tracts get their name from the nerve processes that extend from the cerebral cortex down to the spinal cord. a. true b. false
true
62. As we grow older, our muscles tend to have a higher percentage of slow-twitch motor units because of a loss of fast-twitch motor units. a. true b. false
true
62. Transport of glucose through the cell membranes and into muscle cells is controlled by insulin. a. true b. false
true
63. During cellular metabolism, the rate of energy release from chemical compounds is regulated by special proteins called enzymes. a. true b. false
true
63. When stimulated, Golgi tendon organs inhibit contracting (agonist) muscles and excite antagonist muscles. a. true b. false
true
64. Tropic hormones affect the functioning of other endocrine glands. a. true b. false
true
68. Fast-twitch muscle fibers are best suited for glycolytic energy production. a. true b. false
true
69. During near-maximal exercise, significant amounts of lactic acid are generated by the ATP-PCr energy system. a. true b. false
true
71. Fat provides more kilocalories per gram than carbohydrate, but oxidation requirements for fat are greater than oxidation requirements for carbohydrate. a. true b. false
true
72. The body stores much more energy in the form of fat than in the form of glycogen. a. true b. false
true
34. Slow-twitch (ST) muscle fibers are also sometimes referred to as a. type I fibers b. type IIa fibers c. type IIc fibers d. type IIx fibers
type I fibers
mitochondria; glycolytic
type I fibers: greater oxidative capacity: -more __ -high oxidative enzyme concentrations -type II better for __ energy production Endurance training: -enhances oxidative capacity of type II fibers -develops more (and larger) mitochondria -more oxidative enzymes per mitochondrion
VO2 drift- what it is and what its due to
upward slow drift of VO2 during prolonged submax, constant power output exercise. Even observed at low power outputs well below LT although the magnitude of the drift is much less. The drift is possibly due to increased ventilation and catecholamines
30. Which of the following measurements is necessary when assessing the rate of protein metabolism by the body? a. fecal protein content b. urinary nitrogen excretion c. volume of expired carbon dioxide d. respiratory exchange ratio
urinary nitrogen excretion
46. The QRS complex represents
ventricular depolarization and occurs as the impulse spreads from the AV bundle to the Purkinje fibers and through the ventricles
Axon terminals have the ____ with neurotransmitters.
vesicles
The occipital lobe is responsible for _____ input and interpretation.
visual
excessive post-exercise oxygen consumption
volume of oxygen consumed during the minutes immediately after exercise ceases that is above normally consumed at rest
Skeletal are voluntary or involuntary; striated or unstriated; make up ____-skeletal system.
voluntary, striated, musculo (musculo-skeletal)
Smooth muscles are involuntary and found in the ____ of most internal ____ and ____ vessels. They constrict or ____ to regulate ____ ____.
walls, organs, blood, dilate, blood flow
1. Which of the following is not considered a fuel nutrient? a. carbohydrate b. fat c. water d. protein
water
The primary purpose of ADH is to promote ___.
water retention
blood vessels
way to transmit nutrients during activity
inorganic phosphate, heat, lactate, hydrogen ions
what are the 4 by-products most likely to be connected to fatigue?
growth hormone, thyrotropin (TSH), adrenocorticotropin (ACTH), prolactin, FSH; all except GH and prolactin.
what are the 6 hormones released by the anterior pituitary gland? which 4 are tropic, meaning they affect the functioning of other endocrine glands?
hyperglycemia
when plasma glucose is elevated. -insulin released into the blood as a response to promote generation of glycogen and inhibit generation of more glucose.
hemoconcentration
when sweating causes electrolytes to become concentrated in the blood plasma as more fluid, compared to electrolytes, leaves the plasma, it's called __. -this increases the plasma osmolality
sarcoplasmic reticulum
where calcium ions are stored and eventually released in order to allow muscle contraction to occur
kidneys
while the primary regulator of aldosterone release is plasma electrolyte concentration, a second set of hormones from the __ determine aldosterone concentration and thus helps regulate body fluid balance.
Metabolic rate is based on
whole-body O2 consumption and corresponding caloric equivalent
myofibril
within the muscle fiber, and contains the sarcomeres (contractile units)
mass action effect
-substrate availability affects metabolic rate -more available substrate = higher pathway activity -excess of given substrate = cells rely on that energy substrate more than others. p.54
69. Which of the following is incorrect regarding hemoconcentration?
(1.) Plasma water (volume) decreases (2.) Actual number of RBC stays constant, BUT number of RBC per unit of blood INCREASES! (3.) Increases oxygen carrying capacity
dendrites
-the neuron's receivers -how stimuli enters cell body of neuron
14. Steroid hormones:
- Have a chemical structure similar to cholesterol, since most are derived from cholesterol. For this reason they are soluble in lipids and diffuse rather easily through cell membranes.--Includes hormones secreted by:--Adrenal cortex (cortisol & aldosterone) - The ovaries (estrogen & progesterone) - the testes (testosterone) --The placenta (estrogen and progesterone) p. 60
17. Prostaglandins
- Not a hormone. They mediate the effects of hormones. They also act directly on blood vessels to promote swelling and vasodilatation. They are important mediators of the inflammatory response. They sensitize nerve endings of pain fibers thus promote both pain and swelling.
protein
-substrate -can be used as minor energy source under some circumstances but must be converted into glucose first -circumstances of energy depletion or starvation, protein may be used to generate FFAs for energy -only amino acids can be used to make ATP
axon
-the neuron's transmitter -conducts impulses away from the cell body
18. Catecholamines
- epinephrine and norepinephrine are collectively called catecholamines. Produced by adrenal glands.
ATP-PCr system Glycolytic system Oxidative system
-ATP storage is limited -body must constantly synthesize new ATP -three ATP synthesis pathways --__ --__ --__
70. The movement of fluid out of the capillaries is dictated by the pressures inside the capillaries and the osmotic pressure exerted by the proteins in blood mostly...
Albumin
carbohydrate
-substrate -converted to glucose -when resting, is stored in muscles and liver as glycogen -is the primary energy source for muscles and brain so must rely on dietary carbs to replenish stores. -converted back to glucose when needed to make more ATP
substrate
-fuel sources from which we make energy (ATP) -carbohydrate, fat, protein
sodium-potassium pump
-maintains a constant RMP of -70mV in nerve cell -3 Na+ out of cell per 2 K+ brought in.
nonsteroid hormones
-not lipid soluble -does not easily cross the cell membrane -protein/peptide hormones or amino acid derived hormones
36. Physiological mechanism(s) responsible for the EPOC include
-O2 debt, rebuilding ATP and PCr, removal of lactate. The mechanisms are not clearly defined (page 109 last sentence before Lactate Threshold) But they were thought to be because the O2 requirement at exercise is higher than at rest when one ends exercise they breath more O2 than required at rest. It was thought it was for the rebuilding of ATP and PCr (fast component) and the removal of accumulated lactate from the tissue (slow component)
growth hormone
-potent anabolic agent -promotes muscle growth and hypertrophy by facilitating amino acid transport into the cells. -directly stimulates fat metabolism (lipolysis) by increasing the synthesis of lipolytic enzymes. -concentrations elevated during both aerobic and resistance exercise in proportion to eh exercise intensity and typically remain elevated for some times after exercise.
bioenergetics
-process of converting substrates into energy -performed at cellular level
joint kinesthetic receptors
-sensitive to joint angles, rate of angle change -sense joint position, movement
neuromuscular junction
-site of communication btw neuron and muscle fiber -consists of synapse between alpha motor neuron and muscle fiber -where communication btw the nervous and muscular system occurs.
oxidative system
-aerobic -ATP yield: depends on substrate --32 to 33 ATP/ 1 glucose --100+ ATP/ 1 FFA -duration: steady supply for hours -most complex of 3 bioenergetic systems -occurs in the mitochondria, not cytoplasm
glycolytic system
-anaerobic -ATP yield: 2 to 3 mol ATP/ 1 mol substrate -duration: 15sec to 2 mins -breakdown of glucose via glycolysis
ATP-PCr system
-anaerobic, substrate-level metabolism -ATP yield: 1 molATP/1 mol PCr -duration: 3 to 15 sec -bc ATP stores are very limited, this pathway is used to reassemble ATP -contains phosphocreatine (creatine phosphate)
neurons
-basic structural unit of nervous system -individual nerve fibers (nerve cells) -consists of cell body (soma), dendrites, and axon -referred to as "excitable tissue"
glycogen depletion
-causes fatigue -in events lasting longer than a few seconds, muscle glycogen becomes the primary energy source for ATP synthesis -glycogen stores are limited and deplete quickly -used more rapidly during the first few minutes of exercise than later stages. -sensation of fatigue in long term exercise coincides with a decreased concentration of muscle glycogen but not with its rate of depletion. -marathon runners "hitting a wall" attributed to muscle glycogen depletion
intrafusal fiber
-center region can only stretch because not enough or no actin or myosin filaments to contract. -end regions can contract -when stretched, the central region of the muscle spindle also stretched
steroid hormones
-chemical structure similar to cholesterol -soluble in lipids -diffuse easily through cell membrane -testosterone from testes -estrogen and progesterone from ovaries and placenta -cortisol and aldosterone from adrenal cortex
enzyme
-does not start chemical reactions or set ATP yield -do facilitate breakdown (catabolism) of substrates -speed up reactions by lowering the activation energy for a chemical reaction -end with suffix -ase
rate-limiting enzyme
-each step in a biochemical pathway requires specific enzymes -more enzyme activity = more product -__: --can create bottleneck at an early step --decreasing enzyme activity is influenced by negative feedback --slows overall reaction, prevents runaway reaction
fat
-efficient substrate, efficient storage -provides a large portion of the energy used during prolonged, less intense exercise. more energy derived from breaking down a gram of fat than from the same amount of carbohydrate -less readily available for cellular metabolism bc it must first be broken down into components. body stores of potential energy in the form of fat are substantially larger than the reserves of carbohydrate
Possible causes of fatigue 1) 15-30 sec. and 2) 2-4 hours
1) PCr depletion, ATP decreasing, muscle glycogen depletion, possibly lactic acid accummulation --> increased muscle acidosis (increased H+), Failure of muscle fiber's contractile mechanism 2) glycogen depletion, increased muscle temperature, loss of water (dehydration) and electrolytes (high body T)
Three mechanisms through which lactate can be used as an energy source
1) can be taken up in mitochondria and directly oxidized 2) Lactate shuttle: transported to other cells for oxidization 3) transported by the blood to the liver, where it is reconverted into pyruvic acid
13. Intracellular stores of ATP and PCr are sufficient to support maximum muscular effort for approximately a. 3 to 15 seconds b. 1 to 4 seconds c. 30 seconds to 2 minutes d. 1 to 2 hours
3-15 seconds
Normal body fluid osmolality is approximately ____.
300 mOsm/kg
The effects of ADH and aldosterone persist for up to ____hrs after exercise.
48
37. In untrained people, the lactate threshold typically occurs at around
50% - 60% of their VO2max
Type IIx has the contraction speed of __ ms, ___ force production, ___ fatigue resistance, larger fiber size, and ___ resistance on aerobic metabolism (anaerobic).
50, high, low, low
Type IIa has the contraction speed of __ ms, ___ force production, ____ fatigue resistance, large fiber size, and ____ ___ reliance on aerobic metabolism.
50, high, moderate, moderately high
41. During a maximal voluntary contraction of a muscle, approximately what percentage of the motor units within the muscle are activated? a. 10 to 20% b. 30 to 40% c. 50 to 70% d. 100%
50-70%
The cell membrane of a typical neuron at rest has a negative electrical potential of about _____.
70mV
adenosine diphosphate (ADP)
A high-energy phosphate compound from which ATP is formed
indirect calorimetry
A method of estimating energy expenditure by measuring respiratory gases O2 and CO2. -limited to steady-state aerobic activities lasting a few minutes or longer, which takes into account most daily activities including exercise -the most widely and most accurate estimate of energy expenditure at rest and during aerobic exercise
7. Muscle contraction requires energy. Which of the following is (are) correct?
Break down of ATP, ATP binds to myosin, used to power tilt of myosin head
54. Which of the following is a true statement regarding diffusion of oxygen and carbon dioxide across the respiratory membrane?
CO2 diffuses rapidly across the membrane in spite of a relatively small pressure gradient
32. The respiratory exchange ratio (RER) is defined as the ratio between the
CO2 released to the oxygen consumed RER = VCO2 / VO2
30. Which of the following areas within the central nervous system appears to be particularly important in coordinating body movements?
Cerebellum.
_____ is the primary glucocorticoid, leading to the mobilization of FFAs and breakdown of protein into amino acids. p.106
Cortisol
(Ch 6) 51. Which of the gas laws explains the sum of partial pressures in a mixture of gases?
Dalton's law
71. The ability to hold your breath longer during swimming after a period of hyperventilation is due to
Decreased carbon dioxide in the blood.
concentric contraction; eccentric contraction
Dynamic Contraction Subtypes: -__: --muscle shortens while producing force --most familiar type of contraction --sarcomere shortens, thin filaments slide toward center of sarcomere -__: --muscle lengthens while producing force --cross-bridges form but sarcomere lengthens --ex: lowering heavy weight
48. Stroke volume equals
EDV (end diastolic volume) - ESV (end systolic volume) (in mL) or.... EF (ejection fraction) x EDV or.... Q / HR
35. The difference between the oxygen required during a given rate of steady-state work and the oxygen actually consumed is referred to as the
EPOC
length-tension; speed-force; concentric; eccentric
Generation of Force: -__ relationship: --optimal sarcomere length = optimal overlap --too short or too stretched = little or no force develops -__ relationship: --__: maximal force development decreases at higher speeds --__: maximal force development increases at higher speeds
What increases when glycogen depletes
FFA metabolism, but if this is too slow it may be unable to supply sufficient ATP for a given intensity
T/F: ADH promotes the retention of water by stimulating the retention of Na+.
False
T/F: Epinephrine is secreted by the adrenal cortex and plays a key role in physical recovery after exercise.
False
T/F: Glucagon is a potent glucocorticoid that promotes mobilization of stored fuel substrates and exerts anti-inflammatory effects.
False
T/F: Growth hormone (secreted by the adrenal gland) is a potent catabolic agent, stimulating breakdown of glucose during exercise.
False
T/F: Norepinephrine and cortisol are secreted by the adrenal medulla during exercise, leading to an increase in the fight-or-flight response.
False
T/F: The level of a given hormone's activity is determined solely by its plasma concentration.
False
T/F: Very few hormones in the body are categorized as nonsteroidal.
False
high; slow; FFAs
Fat: -__ net ATP yield but __ ATP production -must be broken down into free fatty acids and glycerol -only __ are used to make ATP
alpha motor neurons; differentiate; fiber; aging
Fiber Type Determinants: -Genetic Factors: --determine which __ innervate fibers --fibers __ based on alpha motor neuron -Training Factors: --endurance vs strength training, detraining --can induce small (10%) change in __ type -__: muscles lose type II motor units
52. Which of the following laws states that the rate of diffusion through a tissue such as the respiratory membrane is proportional to the surface area and the difference in the partial pressure of gas between the two sides of the tissue?
Fick's law
more; less; rate coding
Generation of Force: -motor unit recruitment: --type II motor units = __ force --type I motor units = __ force --fewer small fibers vs more large fibers -Frequency of stimulation (__) --twitch: smallest contractile response of a muscle fiber or a motor unit to a single electrical stimulus --summation: series of three stimuli in rapid sequence before complete relaxation form the first stimulus --tetanus: continued stimulation at higher frequencies can lead to this, resulting in the peak force or tension of the muscle fiber or motor unit
40. Most researchers agree that the primary cause of fatigue during maximal, all-out exercise lasting more than 30 seconds is (I'm really interested in how you answer this)
From the use of PCr which produces Pi which causes fatigue and also the build up of H+ which lowers muscle pH and impairs the cellular processes that produce energy and muscle contraction
cholecystokinin (CCK); GLP-1; peptide YY; insulin; ghrelin
GI tract hormones: -__: distention of stomach caused by a full stomach triggers this hormone to suppress hunger -__ and __ are secreted from the large and small intestines during and after eating. travel through the blood to the brain to suppress hunger. -__ released from pancreas in response to eating also acts as a satiety hormone. -__: secreted from stomach and pancreas when the stomach is empty. after eating, concentrations of this hormone decreases p.115
fatigue
General sensations of tiredness and accompanying decrements in muscular performance. -inability to maintain the required power output to continue muscular work at a given intensity. -reversible by rest -Causes: --decreased rate of energy delivery (ATP-PCr, anaerobic glycolysis, and oxidative metabolism) --accumulation of metabolic by-products, such as lactate and H+ --failure of the muscle fiber's contractile mechanism --alterations in neural control of muscle contraction
O2 consumed is (greater/less) than O2 demand in early recovery- this replenishes (2)..converts, clears
Greater (this is EPOC)...This replenishes ATP/PcR stores, converts lactate to glycogen, replenishes hemo/myoglibin, and clears CO2...Why pulse and breathing are still elevated for awhile after exercise. Respiration is high to clear CO2 that has accumulated in the tissues as a by-product of metabolism
_____ release is proportional to exercise intensity and notably contributes to growth of tissues, organs, and muscle.
Growth hormone
The M-line is in the middle of the __- zone
H
(Ch 2) 11. The major metabolic waste product that causes the muscles and blood to have a lower pH during exercise of increasing intensity is
H+
36. Type ________ muscle fibers constitute approximately 50% of the total muscle fibers in most muscles of the body in the normal, nonathletic population. a. I b. IIa c. IIx d. IIc
I
38. A person with a high VO2max (subject A) and a person with a low VO2max (subject B) perform at an 8 min pace. It is incorrect that Subject B can perform the 8 min pace with less effort (lower submax VO2) assuming similar economy. V\od\O2max?
If Subject A has a higher VO2max then his percentage of his VO2max will be lower than subject B's percentage of VO2max at this given pace. If they have similar economies then they will be taking up similar O2 per running speed. But since Subject B has a lower VO2max then his submax VO2 will be higher he will be using more energy. V/od/O2max ???
The central nervous system includes both the _____ and _____ _____.
brain, spinal cord
What is the role of calcium in muscle contraction?
It binds to troponin on the actin filament and the troponin pulls tropomyosin off of the active sites allowing myosin to attach to actin
3 characteristics of LT
Lactate prod rate is greater than lactate clearance rate, is an interaction of aerobic and anaerobic systems, good indicator of endurance
SR; stored; resting
Muscle Relaxation: -AP ends, electrical stimulation of __ stops -Ca2+ pumped back into SR --__ until next AP arrives --requires ATP -Without Ca2+, troponin and tropomyosin return to __ conformation --covers myosin-binding site --prevents actin-myosin cross-bridging
gamma motor neurons; alpha motor neurons
Muscle Spindles: -intrafusal fibers are controlled by specialized motor neurons called __. -extrafusal fibers are controlled by __.
4. The thick filaments of a myofibril are composed mainly of
Myosin p. 29
a certain rate of mm glycogenolysis is required to maintain
NADH production in Krebs Cycle, e- transport chain activity (no glycogen=inhibited substrate oxidation)
Aldosterone release leads to ___.
Na+ retention followed by water retention
____, where a hormone-mediated change int he body in turn inhibits further hormone secretion, often regulates hormone secretion.
Negative feedback
31. Why is the following statement incorrect? To calculate oxygen consumption using the Haldane transformation, it uses the assumption that the volume of nitrogen inspired is greater than the volume of nitrogen expired.
Nitrogen concentration stays the same. You can calculate the Volume of air inspired from the Haldane transformation not the oxygen consumption.
cell surface; second messenger; cAMP
Nonsteroid Hormones: 1) the nonsteroid hormone binds to receptor on __. 2) this triggers a series of reactions that lead to formation of an intracellular __ that can relay signals and intensify strength of signal. one important one is __. 3) can result in many different outcomes
intensity; limited
Oxygen needs of muscle: -as __ increases, so does ATP demand In response: -rate of oxidative ATP production increases -O2 intake at lungs increases -O2 delivery by heart, vessels increases O2 storage __: use it or lose it O2 levels entering and leaving the lungs accurate estimate of O2 use in muscle
59. Ventilatory regulation appears to be most sensitive to which of the following chemical stimuli?
PCO2 (see google doc for more info)
exercise-associated muscle cramps (EAMCs)
Painful prolonged contractions of muscles that a company or result from muscle contractions -spasmodic, involuntary contractions of skeletal muscles that occur during or after exercise -theory proposes that EAMCs occur when neuromuscular control becomes altered -stretching is most effective way to get rid of them because it increases tension in the golgi tendon organ that inhibits the alpha motor neuron -another type of cramp is heat cramp (p. 145)
_____ are "local hormones" that exert their effects (often associated with inflammation and pain) in the immediate area where they are produced.
Prostaglandins
5. Calcium binding to troponin is the trigger mechanism to initiate contraction in skeletal muscle.
Pulling tropomyosin off the active site
At rest RER, VO2, and metabolic rate values
RER~0.80 (when carbs and fats are equal), VO2~0.3 L/min, metabolic rate~2,000 kcal/day
decreased insulin; epinephrine; norepinephrine; cortisol; growth hormone
Regulation of Fat Metabolism During Exercise: -FFAs primary source of energy at rest and during prolonged endurance exercise. -rate of triglyceride breakdown may determine, in part, the rate at which muscles use fat as a fuel source during exercise. -rate of lipolysis is controlled by at least which 5 hormones?
glucagon; epinephrine; norepinephrine; cortisol
Regulation of Plasma Glucose Concentration: -the concentration depends of a balance btw glucose uptake y exercising muscles and its release by the liver. what are the 4 hormones that work to increase the circulating plasma glucose?
renin; Angiotensin-converting enzyme (ACE)
Renin-angiotensin-aldosterone mechanism: -in response to a fall in blood pressure or plasma volume, blood flow to the kidneys decreases. stimulated by activation of the sympathetic nervous system, the kidneys release __. -an enzyme that is released into the circulation where it converts a molecule called angiotensinogen to angiotensin I. -angiotensin I--> ___ in the lungs--> Angiotensin II-->stimulates aldosterone release from adrenal cortex for sodium and water resorption at the kidneys
ergometers; treadmills; cycle
Research Tools: -__ are used to measure physical work in standardized conditions -__ and __ ergometers are most commonly used
muscle contraction; actin; myosin
Sarcomere: protein filaments -used for __. -__: -- Thin filaments --show up lighter under microscope --I-band contains only these filaments -__: --thick filaments --show up darker under microscope --A-band contains both types of filaments --H-zone contains only these filaments
2. The specialized network of membranous tubules that stores calcium ions in a muscle fiber is the
Sarcoplasmic reticulum p. 28
1. The type of muscle that is found in the walls of most internal organs is
Smooth muscle p. 26
68. The ----- nervous system causes a shunting of blood from the circulation ------ to facilitate exercise demands.
Sympathetic; splachnic
11. Which structure within skeletal muscle spreads the nerve impulses rapidly throughout individual myofibrils? a. T-tubules b. sarcoplasmic reticulum c. mitochondria d. nucleus
T-tubules
65. During a graded exercise test, you would expect to see systolic blood pressure rise linearly while diastolic blood pressure changes very little.
TRUE
43. What vagus nerve is under control and functions to heart rate.
The Extrinsic (parasympathetic/sympathetic) decrease if parasympathetic or increase if sympathetic
62. The fact that an increase in end-diastolic volume increases Stroke Volume of the heart is an illustration of
The Frank-Starling mechanism
resting metabolic rate (RMR)
The bodies metabolic rate early in the morning following an overnight fast and eight hours of sleep. Determining RMR does not require sleeping overnight in a laboratory or clinical facility. -most researchers measure this instead of the actual BMR because does not require the stringent standardized conditions associated with a true BMR
17. Which of the following is incorrect? a. Energy from the breakdown of ATP is available to perform work. b. The aerobic conversion of ADP to ATP is oxidative phosphorylation. c. The energy from the breakdown of PCr is directly available to do cellular work. d. The breakdown of a molecule by the addition of water is called hydrolysis.
The breakdown of a molecule by the addition of water is called hydrolysis
oxygen deficit
The difference between the oxygen required for a given exercise intensity (steady state) and the actual oxygen consumption
peak oxygen uptake (VO2peak)
The highest oxygen uptake achieved during a graded exercise test when is subject reaches volitional fatigue before a plateau occurs in the VO2 response (the criterion for a true VO2max)
65. Discuss the size principle and the principle of orderly recruitment in regard to activation of motor units during exercise.
The order of motor unit recruitment is directly related to the motor neuron size. The smallest motor units are recruited first and then larger ones (graded recruitment). Motor units are activated on the basis of a fixed order: Type I, Type IIa, Type IIx
What does O2 usage during metabolism depend on
The type of fuel (carb, fat, protein) being oxidized
31. Which of the following muscle fiber types typically constitutes the largest percentage of the total muscle fibers in most human muscles? a. Type IIa b. Type IIc c. Type IIx d. Type I
Type I
prolonged; ATP; low-intensity; fat
Type I fibers during exercise: -High aerobic endurance: so oxidation is an aerobic process --can maintain exercise for __ periods --require oxygen for __ production. --__ aerobic exercise (marathon running), daily activities in which muscle force requirements are low (like walking) -efficiently at producing ATP from the oxidation of __ and carbohydrates
type II; Ca2+; type I; type II
Type I vs Type II: -sarcoplasmic reticulum: --__ fibers have a more highly developed SR --faster __ release, 3 to 5 times faster Vo -motor units: --__ motor unit: smaller neuron, <300 fibers --__ motor unit: larger neuron, >300 fibers
IIx; IIa; I; 20%
Type I vs Type II: peak power -type __ > type __ > type _ --effects of different SR, motor units, etc. --single muscle fiber recording -regardless of fiber type, all muscle fibers reach a peak power at __ peak force
63. The order of fiber recruitment with increasing muscular force (light to maximal
Type I, Type IIa, Type IIx
quickly; anaerobically; faster; high-intensity; explosive
Type II fibers during exercise: -Type II fibers in general: --poor aerobic endurance, fatigue __ --produce ATP __ -Type IIa --more force, __ fatigue than type I --short, __ endurance events -Type IIx --seldom used for everday activities --short, __ sprints
37. Which of the following does not appear to be true concerning muscle fiber types? a. Slow-twitch fibers rely mainly on aerobic metabolism for energy. b. The distribution of muscle fiber types within an individual's muscles is determined primarily by the person's genetic makeup. c. Type IIa muscle fibers are used primarily for low-intensity muscular efforts of prolonged duration. d. All the fibers of a given motor unit are of the same fiber type.
Type IIa muscle fibers are used primarily for low-intensity muscular efforts of prolonged duration
35. Low oxidative capacity, high glycolytic capacity, fast contraction speed, and a low level of fatigue resistance are characteristics of a. Type IIx fibers b. Type IIa fibers c. Type IIc fibers d. Type I fibers
Type IIx fibers
Longitudinal studies
Type of research design that are more than often accurate than cross-sectional studies but are time consuming and expensive. preferred method to study data. allows cause and effect
Cross-sectional research
Type of research design that collects data from a diverse population and compares groups in the population. doesn't allow looking at cause and effect
Longitudinal research
Type of research design that test the same subjects and compares results over time
static (isometric) contraction; dynamic contraction
Types of Muscle Contraction: -__: --muscle produces force but does not change length -- joint angle does not change -- myosin cross-bridges form and recycle, no sliding -__: --muscle produces force and changes length --joint movement produced
RER=
VCO2/VO2
34. Ventilatory drift
VO2 Drift is defined as a slow increase in VO2 during prolonged, submaximal, constant power output exercise.--It is different from the slow component because it is observable at power outputs below lactate thresholds and the magnitude of the increase in VO2 drift is much less.
45. The T-wave represents
Ventricular repolarization
How is maximal O2 uptake measured and what is its relationship to sport performance?
Vo2max can be estimated by submaximal and maximal test, direct and indirect calorimetry Vo2max is a good predictor of success in endurance events and increases with training (5-20%). The more oxygen you can take in and use at higher levels, the more ATP you can produce through oxidative system, thereby delaying fatigue
smooth muscle, cardiac muscle, skeletal muscle
What are the three types of muscle tissue?
Trends in data, response patterns, and comparisons of data between subject groups
What do graphs better illustrate?
Two reasons there is a difference in VO2 max for women and men
body composition differences- women have less FFM and more fat mass, and blood hemoglobin content is lower in women and therefore have a lower O2 carrying capacity
17. The primary mechanism responsible for maintaining the resting membrane potential of a neuron is a. the high concentration of potassium ions outside the neuron b. the high concentration of sodium ions inside the neuron c. the impermeability of the neuronal membrane to electrolytes such as sodium and potassium ions d. active pumping of sodium and potassium ions across the neuronal membrane by the sodium-potassium pump
active pumping of sodium and potassium ions across the neuronal membrane by the sodium-potassium pump
Why do athletes with high Vo2max values perform better in endurance activities than those with lower values?
ability to perform at a higher VO2max and being able to maintain VO2 max (or a % of Vo2max) for prolonged times indicates that the individual is able to take in more oxygen to be converted into energy for endurance activity
22. What substance is released at the neuromuscular junction? a. glucose b. phosphofructokinase c. acetylcholine d. acetylCoA e. None of these is correct
acetylcholine
23. The primary neurotransmitter released by motor neurons and by most parasympathetic neurons is a. norepinephrine b. acetylcholine c. epinephrine d. acetylcholinesterase
acetylcholine
The principal neurotransmitter of the motor division of the peripheral nervous system is ______.
acetylcholine
25. Two major neurotransmitters involved in regulating our physiological responses to exercise are
acetylcholine and norepinephine.
57. Troponin and tropomyosin are structural elements within a myosin myofilament. a. true b. false
actin
18. The primary contractile proteins in muscle are: a. actin and myosin b. troponin and titin c. actin and troponin d. myosin and tropomyosin
actin and myosin
26. The A-band of a sarcomere contains a. actin and myosin filaments b. actin filaments only c. myosin filaments only d. neither actin nor myosin
actin and myosin filaments
actin; tropomyosin; troponin
actin: -actually composed of 3 proteins --__: forms the backbone of the filament --__: tube shaped protein that twists around the actin strands --__: more complex protein that is attached at regular intervals to both the actin stands and the tropomyosin -one end of each thin filament is attached to a z-disk -equally spaced out by titin
For an impulse to travel the full length of a neuron, a(n) ____ ____ must be generated.
action potential
11. Which of the following is incorrect? a. For a neuron to transmit an impulse, the impulse must travel almost the entire length of the neuron. b. Although a graded potential may result in depolarization of the entire cell membrane, it is usually just a local event, and the depolarization does not spread very far along the neuron. c. To travel the full distance, an impulse must generate an action potential. d. Action potentials can be generated even if a threshold is not met.
action potentials can be generated even if a threshold is not met
The ___ is the neuron's transmitter and conducts impulses away from the cell body.
axon
On a side toward the axon, the cell body tapers into a cone shaped region known as the ____ _____.
axon hillock
Near its end, the axon splits into numerous end branches; they are dilated into tiny bulbs known as ___ ____.
axon terminals
61. Indirect calorimetry a. assesses the body's energy expenditure by measuring heat production b. can track rapid changes in energy expenditure, whereas direct calorimetry cannot c. uses measurements of respiratory gases in estimating energy expenditure d. a and b e. b and c
b and c
calorie
basic unit of heat
heat produced
because all energy eventually degrades to heat, the amount of energy released in a biological reaction can be measured from amount of __.
glucose-6-phosphate
before either glucose or glycogen can be used to generate energy, it must be converted to a compound called __. -this conversion requires input of 1 ATP for glucose -glycogen does not use any ATP when it converts to this though
26. The name of the process and what it accomplishes before fatty acids can be used as a fuel are a. beta-oxidation, breaking off pairs of carbons to form acetyl CoA b. lipogenesis, anabolized into a triglyceride c. transamination/deamination, the addition of a phosphate d. gluconeogenesis, making new glucose from a noncarbohydrate source
beta-oxidation, breaking off pairs of carbons to form acetyl-CoA
53. Carbon dioxide is transported in the blood principally as
bicarbonate ion
How is lactate threshold measured and whats its relationship to sport performance
blood lactate samples; increases as intensity increases; reflects interaction between aerobic and anaerobic energy systems; ability to exercise at high intensities without accumulating lactate is beneficial to athletes because lactate accumulation contributes to fatigue; LT is major determinant of pace that can be tolerated during a endurance event
Two possible markers of anaerobic capacity
blood lactate threshold: higher blood lactate threshold indicates being able to exercise for longer periods before fatiguing EPOC: EPOC as an indicator of the amount of anaerobic activity that had occured (shows the amount of lactic acid in tissues, that needs to be removed in order to store depleted glycogen stores --> glycogen used in anaerobic glycolysis