Studied by 5 people
exercise physiology
the scientific study of the acute and chronic biochemical and physiologic changes of the human body to exercise
kreb’s cycle
metabolic production of 38 ATP occurs
T/F: the more bonds there are, the more energy is required to break them (Hydrogen - 1 bond is easier to break than Carbon - 4 bonds)
true
metabolism
energy production that is primarily concerned with Hydrogen, Oxygen, Nitrogen, and Carbon
how much ATP is used by a human at rest per day?
99 lbs
thermodynamics
the relationship between heat and other forms of energy (mechanical, electrical or chemical)
law of conservation of energy
1st law of thermodynamics
the body does not produce, consume, or use up energy; rather, it transforms it from one form into another as physiological systems undergo continual change and need for energy
if we use 99 lbs of energy (ATP) every day, why aren’t we losing 99 lbs every day?
because we are using our energy to make more energy (1st law of thermodynamics)
energy
controlled by the laws of thermodynamics and is needed by all of the body systems; the capacity to do work
how does the body use energy?
ATP moves from the body’s storage tank (fats, carbs, proteins) to the muscle cells
thermo
heat or energy
dynamics
change, movement, transfer
where does our body’s energy come from?
fats, carbs, proteins
how is potential energy from the earth and body utilized?
it must be:
–extracted (taken out and refined)
–harnessed (controlled and used)
–produced (broken down and converted to a usable energy source)
potential energy
stored energy in a system that is not yet used and can be transferred to other systems
different forms: light, chemical, mechanical, etc.
when two forces hit each other, __ is produced and energy is generated
heat
kinetic energy
energy of motion/in use that is formed by the transformation of potential energy
what factors have an effect on energy movement?
gravity, concentration, pressure, temperature
gravity
moves toward the center of the earth
concentration
force moved from an area of high concentration to low concentration
pressure
force moves from an area of high pressure to low pressure
temperature
moves from one temperature extreme to another
second law of thermodynamics
determines the direction of energy flow based on movement and likelihood
-→ transfer of heat and cold
-→concentration gradient
concentration gradient
-movement rom an area of high concentration to low concentration
-energy moves from an area of high energy to an area of need
-CANNOT go the opposite direction (think of mio in water)
what does the 2nd law of thermodynamics measure?
the likelihood that a reaction (heat/energy transfer) will occur in both directions without help
aka the degree of disorder and randomness in the system, plus the amount of energy needed to fuel that change
Disorder + Heat Transfer Effect
unless energy is expended to _____ the energy in one system, they will balance, and the energy transfer will cease
replenish
why must we continually put energy into our bodies?
because we do not absorb energy
the human body cannot create ____, but stores _____, thus creating an imbalance
energy; potential chemical energy
upon release, the chemical energy transfers to _____, in a high concentration to low concentration fashion, producing movement
mechanical and heat energy
for activity (or change) to continue, more _________ must be created and released
potential energy
__ex__ergonic reactions
-energy that is __ex__iting
-chemical processes that release energy to its surroundings/into a system
-downhill processes
endergonic reactions
-__en__ergy that is entering
-chemical processes that store or absorb energy
-uphill processes
ATP energy sources
-food
-refinery (digestion)
-cells and muscles (stores and produced ATP, and distributed for use)
using energy
the bonds holding a chemical compound together and broken to release energy
making energy
energy is also required to re-connect two chemicals to re-form a compound
bioenergetics
the study of the transfer of energy in living organisms
mechanical work
an object of some mass is moved a vertical distance
metabolic work
the physical and chemical processes necessary for a body to create and use energy to perform movement
what is the cumulative effect of all the endergonic and exergonic reactions
metabolic work
what two main processes continually occur during metabolic work?
anabolism and catabolism
anabolism
the process of building new materials for the body to use
catabolism
the process of breaking things apart
-the breakdown of muscle protein
-use the potential energy stored in food
physiological work
the adaptation of the physiological systems of the body in response to physical stresses
psychological work
an individual’s perception of the difficulty in the performance of a physical task
muscle contraction is an example of
mechanical work
breaking down and storing potential energy from food is an example of
chemical work
sodium potassium pumps are an example of
transport work
what are the 3 types of work in the human body?
mechanical work
chemical work
kinetic or movement (transport) work
passive (transport) work
requires a concentration or pressure gradient
2 kinds:
diffusion
facilitated
diffusion
movement of cells across a membrane
active (transport) work
requires energy to make the cells move in that direction
what are the three types of cellular transport?
diffusion through lipid bilayer (passive)
facilitated diffusion (passive)
active transport
_______ energy comes from the food we take in or the fat we already have stored; if there is no food or stored fat, the body will break down muscle mass to get energy
potential
food energy
comes from carbs, lipids, proteins
ADP + Pi ---→ ATP
Pi
a phosphate
ATP
tail end is 3 phosphate bonds that can store large amounts of potential energy
what happens when the body requires energy?
the last ATP phosphate bond is broken, energy is released, and work can be done
ATP-→ ADP -→ AMP
ADP
adenosine + Pi + Pi
AMP
adenosine + Pi
____ in muscle can cause changes to occur which makes the muscles pull together
ATP
how much ATP is store in the muscle?
a few seconds of work (<0.25 lb)
what three things happen why ATP is split?
ADP is formed
Pi (inorganic phosphate) is split off
energy (7.3 kCal) is released
ATP minus P (a phosphate molecule) = ADP + energy
energy traveling AWAY = EXERGONIC rxn
Energy + P (a phosphate molecule) + ADP = ATP
energy traveling TOWARDS = ENDERGONIC rxn
enzymes
proteins that serve as a biological “gas pedal” to speed up rxns
highly specific proteins
are neither consumed nor changed in the rxn
coenzymes
complex non-protein organic substances that connect with the enzymes and serve as the “foot on the gas pedal” to help make them go
do enzymes and coenzymes change the chemical compounds they attach to?
no, they just help speed them up
how can you recognize an enzyme?
by the suffix -ase on the end of the rxn it is speeding up (ex: ATPase)
when does an enzyme turn on?
when its active site joins with a substrate’s binding site (coenzyme)
what factors affect the speed of a rxn by affecting enzyme activity?
pH (acidity)
temperature
3rd law of thermodynamics
the normal action (behavior) of a system slows to the point of almost stopping when the temperature reaches “absolute zero” (0 degrees K)
T/F: the breakdown of ATP for a muscle contraction produces energy, which results in ADP
true
in order to reconnect the phosphate to the ADP to form ATP, a ____________ must occur
chemical rxn
T/F: we have an unlimited capacity to store readily available ATP
false - we have limited capacity
energy requirements vary based on what?
intensity, duration, fitness level of the performer
what are the 2 methods for ATP production?
anaerobic and aerobic
anaerobic
–occurs in the absence of molecular oxygen
–process takes place in the cytosol (liquid) inside of the cell
aerobic
–requires molecular oxygen
–process takes place in the mitochondria
3 systems for ATP replenishment
ATP-PC system (anaerobic-high power/short duration)
glycolytic system (anaerobic-moderate power/short duration)
oxidative system (aerobic-low power/long duration)
what determines which energy system(s) is relied on?
effort and duration
one time movement like a box jump would rely on what energy system?
ATP-PC
repeated movements like jumping rope relies on which energy system?
glycolytic
extending movement like a marathon requires which energy system?
oxidative
at rest what two sources are equally used for energy?
fats and carbs
what source is used during light exercise for energy
fats (free fatty acids)
what source is used during steady exercise?
carbohydrates (when FFAs are used up)
the metabolic “left-overs” or by-products are converted into these two basic substances depending on the intensity and duration of the exercise or activity:
pyruvate
lactic acid
pyruvate enters what cycle?
krebs
lactic acid enters what cycle?
cori cycle
during lower intensity exercise:
-pyruvate is produced
-acetyl Co-A if formed from pyruvate entering the krebs cycle
during higher intensity exercise:
-lactic acid is produced
-body needs to buffer (neutralize) the acidity
buffering of lactic acids during extended duration exercise (>2 min) causes the production of?
CO2 and H2O
ATP-PC system
-provides max effort lasting ~10-12 seconds from ATP stored in muscles
-anaerobic
-1 enzyme rxn
-speeds up connection between ADP and a phosphate to make ATP
glycolytic system
–__F__ast __A__naerobic __G__lycolysis aka (FAG) or [Fast]
–__F__ast __O__xidative __G__lycolysis aka (FOG) or [Slow]
-anaerobic
-carbs break down glucose supply that circulates in the blood
__F__ast __A__naerobic __G__lycolysis aka (FAG) or [Fast]
high intensity activity lasting longer that ~30 secs results in pyruvic acid conversion to lactic acid which causes muscle fatigue
lactate
can be used 3 ways:
–directly by the cell which produced it (oxidative through the mitochondria)
–shuttle to a neighbor cell
–go to the liver (Cori cycle)
the cori cycle
-lactate formed in the muscle cells is transported to the liver where it is converted into glucose (gluconeogenesis)
-glucose is then taken back to the muscle and used to fuel muscular activity
lactate accumulation causes:
-acidic pH in the cell
-enzymes affected = slow glycolysis
-energy not created fast enough and fatigue occurs
Note 
Flashcard (20)