Midterm 1 : Chapters 2,3,4,5 Flashcards
(183 cards)
1
Q
___________ fuel sources from which we obtain energy (ATP) and carbohydrate, fat, protein.
A
Energy Substrates
2
Q
________ process of converting substrates into energy, and occurs at cellular level
A
Bioenergetics
3
Q
_______ chemical reactions in the body
A
metabolism
4
Q
energy released from a biological reaction can be calculated from .?
A
heat produced
5
Q
What are the main fuels for exercise?
A
carbohydrates, fats, protein also referred to as carbon, hydrogen, oxygen, and sometimes nitrogen
6
Q
energy from chemical bonds in food stored in high-energy compound: ?
A
ATP
7
Q
all carbohydrate is converted to?
A
glucose
8
Q
about _____ carbohydrates is stored in the body?
A
- 4.1 kcal/g
- 2,500 kcal
9
Q
Carbohydrate converted to glucose would be the primary ATP substrate for ?
A
muscles & brain
10
Q
When you have extra glucose what happens to it?
A
glucose is stored as glycogen in the liver and muscles
11
Q
______ can be converted back to glucose when needed to make more ATP.
A
glycogen
12
Q
When glycogen stores are limited; rely on dietary _____ to replenish.
A
carbohydrate
13
Q
Fat is an efficient substrate with efficient storage with about how much stored in the body?
A
- 9.4 kcal/g
- +70,000 kcal stored in body
14
Q
Fat substrate for prolonged, less intense exercise must be broken down from _____ into _______ and _______.
A
triglyceride; free fatty acids (FFAs); glycerol
15
Q
Protein used as energy substrate during starvation should have _____ stored in the body and must be converted into glucose via gluconeogenesis.
A
4.1 kcal/g
16
Q
Protein can also be converted into ______ via lipogenesis, for energy storage, and for cellular energy substrate.
A
FFAs
17
Q
Free energy released at a controlled rate depends on 2 factors:?
A
- availability of the primary substrate
- enzyme activity
18
Q
What do enzymes do?
A
- are protein molecules
- do not start chemical reactions
- facilitate breakdown (catabolism) of substrates
- lower the activation energy form a chemical reaction
19
Q
T/F ? Enzyme activity affects metabolic rate
A
True
20
Q
if there is an increase in enzymes o enzyme activity the there is _____ in product.
A
an increase
21
Q
T/F ? ATP stored in small amounts until needed.
A
True
22
Q
Phosphorylation can occur ?
A
in absence or presence of O2.
23
Q
What are the three ATP synthesis pathways:
A
- ATP-PCr system (anaerobic metabolism)
- Glycolysis (anaerobic metabolism)
- Oxidative phosphorylation (aerobic metabolism)
24
Q
ATP-PCr system starts with?
A
phosphocreatine (PCr)
25
_____ energy cannot be used for cellular work, but can be used to reassemble ATP.
PCr
26
_____ replenishes ATP stores during rest.
PCr
27
Glycolytic system uses ____ process.
anaerobic
28
pathway starts with ________, ends with _______. there are 10 to 12 enzymatic reactions total and all steps occur in cytoplasm.
glucose-6-phosphate; pyruvic acid
29
pathways have an enzyme that control overall rate, can create bottleneck at an early stage, activity influenced by NEGATIVE FEEDBACK, and slows overall reaction, prevents runaway reaction would be considered as?
rate-limiting enzyme
30
What is the most common rate-limiting enzyme?
PFK
31
What would be the cons of the glycolytic system?
- low ATP yield, inefficient use of substrate
- lack of o2 converts pyruvic acid to lactic acid
- lactic acid impairs glycolysis, muscle contraction
32
What would be the pros of the glycolytic system?
- allows muscles to contract when o2 limited
| - permits shorter term, higher-intensity exercise
33
T/F ? Oxidative Phosphorylation uses the aerobic process.
True
34
Oxidative Phosphorylation occurs in the ?
mitochondria
35
what are the 3 stages of oxidation of carbohydrate cycle?
stage 1: glycolysis
stage 2: Krebs cycle
stage 3: electron transport chain
36
pyruvic acid -> acetyl-CoA, then enters?
Krebs cycle
37
NADH and FADH2 molecules carry ____ and ___ to the electron transport chain.
H+; electrons
38
_________ is a group of protein complexes located in the inner mitochondrial membrane.
electron transport chain
39
_____ is the final electron acceptor.
oxygen
40
many chemical compounds are classified as fats such as:
- phospholipids
- cholesterol
- triglycerides
41
________: major fat energy source. These are stored in adipocytes (fat cells), between muscle fibers, and within muscle fibers.
triglycerides
42
what is the process of the oxidation of fat?
- broken down to 1 glycerol + 3 FFAs
- Lipolysis, carried out by lipase
- FFA transported by blood
- enters muscle by diffusion
- ... yields 3 to 4 times more ATP than glucose ... but slower than glucose oxidation
- this process is called beta-oxidation
43
________: structural building blocks, enzymatic function, energy under some circumstances.
protein
44
Where did the lactate come from?
during glycolysis, in anaerobic conditions, pyruvic acid takes hydrogen ions to form lactic acid
45
What are the 3 ways muscles can utilize?
- oxidation
- lactate shuttle
- the cori cycle
46
Oxidation occurs in cells with ___________.
high mitochondrial density ( mostly in type I fibers)
47
What is the Cori Cycle?
starts in muscle as glucose then goes through fast glycolysis to lactate then blood lactate to liver back into glucose then out of the liver as blood glucose and back into the muscle as glucose.
48
Direct Calorimetry: substrate metabolism efficiency has ___ of substrate energy from ATP, and _____ of substrate energy from heat.
40% ; 60%
49
Heat production ______ with energy production.
increases
50
What are the pros of the direct calorimetry?
- directly measures heat
| - accurate for total body energy expenditure over time
51
What are the cons of the direct calorimetry?
- expensive, slow to generate results
- cannot detect rapid changes in energy expenditure
- exercise equipment adds extra heat
- not all heat produced leaves the body; some stored
- sweat affects measurements and calculations
52
Indirect calorimetry is an estimate of?
total body energy expenditure based on O2 used, CO2 produced during oxidative phosphorylation.
53
Called indirect calorimetry because?
- heat production not directly measured
| - estimate of total body energy expenditure
54
Indirect calorimetry can also estimate the composition of ___ ____
fuel oxidized
55
CARBOHYDRATE: During the oxidation of a glucose molecule ___ O2 are consumed and ___ CO2 are produced.
6 ; 6
56
FATS: ___ CO2 are produced for every ___ O2 consumed.
16 ; 23
57
When hyperventilation occurs there is an increase in _____ elimination.
CO2
58
______: rate of energy use by body.
metabolic rate
59
________: rate of energy expenditure at rest.
basal metabolic rate (BMR)
60
V02 max expressed in "absolute" terms is used by?
absolute volume of O2 used by entire body
61
V02 max expressed in "relative" terms is used by?
normalized for body weight
62
__________: point at which blood lactate accumulation increases markedly
lactate threshold
63
an increase in lactate threshold _____ entrance performance
increases
64
as athlete become more skilled, use less energy for given pace = ?
more economical
65
what are the two muscle sorenesses?
- acute muscle soreness
| - delayed-onset muscle soreness
66
acute muscle soreness occurs?
during and immediately after exercise
67
delayed-onset soreness occurs?
one to two days later
68
During acute muscle soreness ... ?
- tissue edema (plasma fluid into interstitial space)
| - disappears within minutes to hours
69
major cause for DOMS is?
eccentric contractions
70
Where are the hormone receptors located?
- steroid (lipid soluble): receptors in cytoplasm or nucleus of target cell
- non steroid (not lipid soluble): receptors on membrane of target cell
71
T/F ? Nervous system is referred to as electrical signals.
True
72
Steroid hormones come from?
cholesterol
73
Phospholipid is made up of?
fat cell walls
74
What is a hormone-receptor complex?
when a hormone binds to a cell
75
when the hormone-receptor complex enter nucleus what happens?
- binds to DNA and activates certain genes
- in response, mRNA synthesized within nucleus
- mRNA enters cytoplasm, promotes protein synthesis
76
Steroid hormone actions consist of which proteins?
- enzymes
- structural proteins
- regulatory; alters enzyme function
77
The endocrine system is a ?
communication system
78
Nonsteroid hormone actions which would be not lipid soluble cannot cross?
cell membrane
79
For nonsteroid hormone actions; the receptors on the cell membrane ?
trigger release of intracellular second messengers
- carry out hormone effects
- intensify strength of hormone signal
80
What are the major glands responsible for metabolic regulation?
- anterior pituitary gland
- thyroid gland
- adrenal gland
- pancreas
81
the anterior pituitary gland is located?
in the front of the brain
82
The growth hormone comes from?
the anterior pituitary gland
83
Growth hormone effects?
- potent anabolic hormone
- builds tissues, organs
- promotes muscle growth (hypertrophy)
- stimulates fat metabolism
84
GH released during aerobic and resistance exercise occurs when?
- proportional to exercise intensity
| - remain elevated after exercise
85
What does the Thyroid gland secrete?
T3 and T4
86
Where is the thyroid gland located?
in the neck
87
What do T3 and T4 do?
- increases:
- metabolic rate of all tissues
- protein synthesis
- # and size of mitochondria
- glucose uptake by cells
- rate of glycolysis and gluconeogenesis
- FFA mobilization
88
Where are the adrenal glands located?
above each kidney
89
What are the two parts of the adrenal gland?
- outter section is referred to as the adrenal cortex
| - deeper section is referred to as the adrenal medulla
90
when the adrenal medulla is stimulated by sympathetic nervous system what happens?
catecholamines are released
- causes "fight-or-flight" response
- epinephrine 80% and norepinephrine 20%
91
when catecholamine is released what happens?
- increase in heart rate, contractile force, blood pressure
- increase in glycogenolysis (glycogen is being broken down)
- increase in lipolysis (fat or trigclerides are being broken down)
increase in blood flow to skeletal muscle
92
The adrenal cortex release?
cortisol (a hormone that breaks things down and catabolic)
93
when cortisol is released what happens?
- increases gluconeogenesis (making new glucose) for fuel
- increases FFA mobilization
- spares glucose for brain
- protein catabolism for repair, enzyme production, gluconeogenesis
94
Where is the pancreas located?
behind and slightly below the stomach
95
What are the 2 major hormones that come from the pancreas?
- insulin
| - glucagon
96
Insulin and glucagon work together to?
control plasma glucose
97
During hyperglycemia ( after a meal), the pancreas releases?
insulin
98
what is the main function of insulin?
lowers (blood glucose)
- counters hyperglycemia
- increases glucose transport into cells (especially muscle)
- increases glycogenesis (creating glycogen)
- inhibits gluconeogensis
99
During hypoglycemia, the pancreas releases?
glucagon
100
what is the main function(s) of glucagon?
increases (blood glucose)
- counters hypoglycemia
- increases glycogenolysis (liver glycogen to glucose)
- increases gluconeogenesis (causes the formation of new sugar)
101
What happens to insulin during exercise?
works better during exercise because it is able to bind receptors on muscle cells
102
what happens to glucagon during exercise?
glucagon increases to maintain plasma glucose
103
glucose must be available to ?
tissues
104
adequate plasma glucose during exercise requires balance between?
- glucose release by liver
| - glucose uptake by muscles
105
Hormones that increase circulating glucose would be?
glucagon, epinephrine, norepinephrine which are all part of glycogenolysis
106
_____: enables glucose uptake in muscle.
insulin
107
during exercise insulin concentrations?
decrease; due to an increase in insulin sensitivity during exercise
108
hormonal regulation of fluid and electrolytes during exercise causes?
- water to shift from plasma volume to interstitial and intracellular spaces
- sweating increases during exercise
109
the fluid in our blood is _____ plasma volume during exercise.
decreasing
110
when plasma volume decreases then ?
there is a decrease in blood pressure and an increase heart strain
111
which glands are involved in monitoring fluid levels and electrolyte balance?
- posterior pituitary gland
- adrenal cortex
- kidneys (not only a target organ; also a gland)
112
Posterioir pituitary gland secretes?
antidiuretic hormone (also called ADH or vasopressin)
113
what does antidiuretic hormone do?
- increases water reabsorption by kidneys, less water excreted in the urine (antidiuresis)
- minimizes water loss and severe dehydration
114
what does adrenal cortex secrete?
aldosterone
115
what does aldosterone effect?
there is an increase in sodium retention by kidneys which leads to an increase in water retention via osmosis
116
kidneys release?
erythropoietin (EPO) that targets bone marrow to stimulate red blood cell (RBC) production
117
Kidneys are a target tissue for?
ADH and aldosterone; can also stimulate renin-angiotensin-aldosterone mechanism
118
What is happening during renin-angiotensin-aldosterone mechanism?
- kidneys sense a decrease in blood volume
| - release enzyme called renin into circulation
119
in circulation renin converts angiotensinogen molecule?
angiotensin I
120
in the lungs, angiotensin-converting enzyme (ACE): converts?
angiotensin I to angiotensin II
121
When angiotensin II reaches adrenal cortex and stimulates?
aldosterone via osmosis
122
gherlin is released?
by the stomach when it is hungry
123
leptin decreases?
hunger
124
people who are obese have?
higher leptin levels but they are resistant to it because the signal is not transmitted through the hypothalamus
125
hormonal regulation of calorie intake during acute exercise causes?
mod-vig aerobic exercise, decreases ghrelin temporarily which will reduce hunger
126
hormonal regulation of calorie intake during chronic exercise causes?
- no change in ghrelin response on people who do not lose weight during exercise training
- ghrelin increases in those who do lose weight
127
nervous system = _______ communication
electrical
128
endocrine system = ______ communication
chemical
129
the endocrine system maintains homeostasis via?
hormones
130
what are hormones and what do they do?
- chemicals that control and regulate cell/organ activity
- secreted into blood
- act on target cells (has specific hormone receptors)
131
Hormones are categorized as?
steroid or nonsteroids
132
What are steroid hormones?
steroids derived from cholesterol, lipid soluble; diffuses through membranes, the major glands that secrete steroid hormones are testes, ovaries, and adrenal cortex
133
what are non steroid hormones?
steroids that are not lipid soluble; cannot cross membranes, divided into two groups; protein/peptide hormones
134
the central nervous system consists of?
brain and spinal cord
135
the peripheral nervous system has which two major nerves?
the sensory (afferent) nerves and effector (efferent) nerves
136
neurons respond to stimuli and convert those messages to an electrical signal called a _______.
nerve impulse
137
What is a neuron?
basic structural unit o nervous system
138
the neuron has three major regions what are there?
- cell body (soma)
- dendrites
- axon
139
What does the cell body contain and what happens inside?
contains nucleus, and cell processes radiate out
140
what does the cell body contain and what happens?
dendrites are the receiver cell processes and carry an impulse towards the cell body
141
what is the axon and what happens?
the axon is the sender cell process, starts at the axon hillock, end branches, and axon terminals
142
electrical signal for communication between _____ and _____.
periphery; brain
143
when charges across membrane differ, membrane is _________.
polarized
144
When there is a difference in electrical charges between outside and inside of cell this is referred to as the ?
resting membrane potential (RMP)
145
according to the resting membrane potential (RMP) the inside is more negative relative to outside: ?
- 70 mV
- caused by uneven separation of charged ions
- high sodium outside cell
- medium potassium inside the cell
146
RMP maintained in 2 ways:
1. membrane more permeable to K+ due to open K+ channels
- K+ will move to less concentrated areas
2. Na+ -K+ pump (primary mechanism)
- actively transports (requires ATP) three Na+ out of cell and two K+ into cell
147
occurs when inside of cell becomes more positive, more Na+ channels open; Na+ enters cell (influx), and is required for nerve impulse to arise and travel would be considered?
depolarization
148
occurs when inside of cell becomes more negative even below -70 mV, more K+ channels open, K+ leaves cell (efflux), makes it more difficult for nerve impulse to arise is considered as?
hyperpolaarization
149
depolarization and hyper polarization contribute to nervous system function via?
graded potentials (GPs)
150
______: localized changes in membrane potential. generated by incoming signals from dendrites, help cell body decide whether to pass signal on.
graded potentials
151
what happens when excitatory postsynaptic potential (EPSP) are in affect?
- na+ channels open = Na+ influx
| - depolarization
152
what happens when inhibitory postsynaptic potential (IPSP) is in effect?
- K+ channels open = K+ efflux
| - hyperpolarization
153
Strong EPSP will lead to an _________.
action potential (AP)
154
if GP reaches ____ to ____ (threshold mV), AP will occur.
-55; -50
155
________: keeps total of EPSPs and IPSPs.
axon hillock
156
what are the 2 characteristics that determine propagation speed: ?
- axon diameter
| - myelin
157
What is the myelin and what happens within it?
- fatty sheath around axon (formed by Schwann cells)
- not continuous (spaces are nodes of Ranvier)
- saltatory conduction
- speeds up propagation
- multiple sclerosis: degeneration of myelin; loss of coordination
158
For neurons to communicate, Paps transfer from a _______ to _____ neuron.
presynaptic; postsynaptic
159
site of neuron-to-neuron communication: ?
synapse
160
axon terminals contain?
neurotransmitters
161
neurotransmitters help with?
- chemical messengers
- carry electrical AP signal across synaptic cleft
- bind to receptor on postsynaptic surface
- stimulate GPs in postsynaptic neuron
162
neurotransmitters bind to receptor at special site:?
motor end plate
163
diencephalon contains?
thalamus and hypothalamus
164
what is the thalamus in charge of?
the sensory relay center; all sensory input (except smell) enters here, regulates what sensory input reaches conscious brain (important for motor control)
165
what is the hypothalamus in charge of?
- maintaining homeostasis (by regulating internal environment) through blood pressure, heart rate and contractility, respirations, digestion, body temperature, thirst and fluid balance, neuroendocrine control, appetite and food intake, sleep-wake cycles
166
where is the cerebellum located?
behind the brain stem
167
what is the cerebellum in charge of?
- controls rapid, complex movements, coordinates timing, sequence of movements, compares actual to intended movements and initiates correction
- assists primary motor cortex and basal ganglia in executing and refining movements
168
What does the brain stem do?
relays information (both ways) between the brain and spinal cord
169
what is the brain stem composed of?
- midbrain
- pons
- medulla oblongata
170
__________ are specialized neurons in brain stem that coordinates skeletal muscle function and tone, controls cardiovascular and respiratory function, and is the pain control system (analgesia)
reticular formation
171
the spinal cord is composed of tracts of nerve fibers that permit two-way conduction of nerve impulses such as?
- ascending afferent (sensory) fibers
| - descending efferent (motor) fibers
172
the peripheral nervous system connects to brain and spinal cord via _____ pairs of nerves
43
173
____ pairs of cranial nerves (originate from brain)
12
174
___ pairs of spinal nerves (originate from spinal cord)
31
175
what are the major families of sensory receptors?
- mechanoreceptors (pressure, touch, vibrations, stretch)
- thermoreceptors (temp.)
- photoreceptors (light)
- chemoreceptors (orders, O2, CO2, glucose, electrolytes)
176
____________: located in joint capsules, sensitive to joint angles and rate of angle change, they sense joint position and movement.
joint kinesthetic receptors
177
_______: sensitive to muscle length, rate of length change
muscle spindles
178
________: sensitive to tension applied by muscle to its tendon, provides information about strength of contraction.
Golgi tendon organs
179
what two divisions does the motor (efferent) division consist of?
autonomic and somatic
180
________: regulates visceral activity
autonomic
181
______: stimulates skeletal muscle activity
somatic
182
_________: fight or flight, increased heart rate, contractility, coronary vessel dilation, peripheral vasodilation for blood flow, etc.
sympathetic system
183
______ : rest and digest, stimulates an increased digestion, uirination, conservation of energy, decreased heart rate, decreased diameter of vessels and airways
parasympathetic system
