Exercise Physiology Flashcards
what is homeostasis?
dynamic constancy and ‘normal’ internal environment
- control systems of the body
- nature of the control systems
what are three examples of a nature of the control system
negative feedback
positive feedback
gain of a control system
what variable is manipulated by the researcher
independent ( on x- axis)
what is stead state
physiological variable is unchanging, but not necessarily ‘normal’
balance between demands placed on the body and the body’s response to those demands (ex. body temp during exercise)
what is intracellular control systems
- protein breakdown and synthesis
- energy production
- maintenance of stored nutrients
what is organ systems
pulmonary and circulatory systems
-replenish oxygen and remove carbon dioxide
what is two of the body’s control systems
intracellular control systems
organ systems
what non-biological control system can the body’s systems be compared to?
a thermostat
what is a biological control system?
series of interconnected components that maintain a physical r chemical parameter at a near constant value
what are the three components of a biological control system?
sensor or receptor
control center
effector
what is a senor
detects changes in a variable
what is a control center?
assesses input and initiates response
what is a effector
changes internal environment back to normal
what is a negative feedback system?
response reverse the initial disturbance in homeostasis
most control systems work via negative feedback
what is a positive feedback system
response increases the original stimulus
example: childbirth
what is a gain of a controls system?
degree to which a control system maintains homeostasis. system with large gain is more capable of maintaining homeostasis than system with low gain. example: pulmonary and cardiovascular systems have large gains
what are three examples of homeostatic control?
regulation of body temperature
regulation of blood glucose
regulation of cellular homeostasis
how does the body regulate body temperature
thermal receptors, sends message to brain the response y skin blood vessels and sweat glands regulate temp
how does the body regulate blood glucose
requires the hormone insulin, diabetes (failure of blood glucose control system)
how does the body regulate the cellular homeostasis
stress proteins (heat shock proteins) -repair damaged proteins to restore homeostasis in response to changes in temperature, pH and free radicals
what would a failure of any component of a control system result in a disturbance of homeostasis
disease
5.1% of adult population suffers from ________
type 2 diabetes
cells synthesize ‘stress proteins’ when ________ is disrupted
homeostasis
ex. heat shock proteins ( chaperone and repair functions)
Hsp90 is part of a family of proteins known as _______ which are solely dedicated to helping other proteins fold and assume their proper functions
chaperones
what is an example of a heat shock protein
Hsp90
when Hsp90 is compromised the number of morphological changes increases, which lead to formation of inactive or abnormally active polypeptides (________ _________)
homeostasis is disrupted
does exercise disrupt homeostasis
yes in many ways
what is metabolism
sum of all chemical reactions that occur in the body
what are the two types of metabolism
anabolic reaction
catabolic reaction
what is anabolic reaction
synthesis of molecules
what is catabolic reaction
breakdown of molecules
what is bioenergetics
converting foodstuffs (fats, protein, carbohydrates) into energy
what is a cell membrane
semipermeable membrane that separates the cell from the extracellular environment (protection)
what is the nucleus
contains genes that regulate protein synthesis
-molecular biology
what is cytoplasm
- fluid portion of cell
- contains organelles (mitochondria)
what are the three major parts of a cell
cell membrane
nucleus
cytoplasm
what are three cellular chemical reactions
endergonic reactions
exergonic reactions
coupled reactions
what is endergonic reactions
require energy to be added
endothermic
what is exergonic reactions
release energy
exothermic
(in a graph looks like stairs)
what is couples reactions
liberation of energy in an exergonic reaction drives an endergonic reaction
the energy given off by exergonic reaction powers the _______ reaction in an ______ reaction
endergonic
coupled
what is oxidation
removing an electron
what is reduction
addition of electron
oxidation and reduction are always _______ reactions
coupled
oxidation-reduction reaction often involved the transfer of ______ atoms rather than free electrons
hydrogen
a molecule that loses a hydrogen also loses an electron and therefore is _______
oxidized
what are the two important components in a oxidation-reduction reaction
NAD and FAD
NAH is an _______ agent
oxidizing
NADH is a _____ agent
reducing
catalysts regulate ____ of reactions
speed
-lower the energy of activation
what are two factors that regulate enzyme activity
temperature
pH
how would you describe an interact with specific substrates
lock and key model
damaged cells release enzymes into the blood which can indicate what?
enzymes levels in blood indicate disease or tissue damage
what is a diagnostic application of enzyme blood levels
elevated lactate dehydrogenase or creatine kinase in the blood may indicate a myocardial infarction
what are the 6 classification of enzymes
- oxidoreductases
- transferases
- hydrolases
- lyases
- isomerases
- ligases
what is oxidoreductases
catalyze oxidation-reduction reactions
what is transferases
transfer elements of one molecule to another
what is hydrolases
cleave bonds by adding water
what is lyases
groups of elements are removed to forma double bond or added to a double bone
what is isomerases
rearrangement of the structure of molecules
what is ligases
catalyze bond formation between substrate molecules
what are two factors that will alter enzyme activity
temperature
pH
how does temperature alter enzyme activity
- small rise in body temperature increases enzyme activity
- exercises results in increased body temperature
how does pH alter enzyme activity
- changes in pH reduces enzyme activity
- lactic acid produced during exercise
what are two carbohydrates
glucose
glycogen
what does glycogen do?
- storage form of glucose in liver and muscle
- synthesized by enzyme glycogen synthase
- glycogenolysis
- breakdown of glycogen to glucose
what are the three fats
fatty acids
phospholipids
steroids
what does a fatty acid do
- primary type of fat used by the muscle
- triglycerides
- storage form of fat in muscle and adipose tissue
- breaks down into glycerol and fatty acids
what does phospholipids do?
not used as energy source
What do steroids do?
derived from cholesterol
needed to synthesize sex hormones
what are proteins composed of?
amino acids
what is gluconeogenesis
protein being converted to glucose in the liver
is protein a primary energy source during exercise?
no
glucose is stored in animal cells as a ________ called glycogen
polysaccharide
what does ATP stand for
adenosine triphosphate
what consists of ATP
adenine
ribose
three linked phosphates
what are the three stages of ATP formation
- phosphocreatine (PC) breakdown
- degeneration of glucose and glycogen (glycolysis)
- oxidative formation of ATP
what are two facts about anaerobic pathways
- do no involve O2
- PC (phosphocreatine) breakdown and glycolysis
what are two facts about aerobic pathways
- require O2
- oxidative phosphorylation
what are the two anaerobic ATP productions
ATP-PC system
glycolysis
what is the ATP-PC system
immediate source of ATP
PC + ADP —–> ATP + C
creatine kinase
what is glycolysis
- glucose–> pyruvic acid or 2 lactic acid
- energy investment phase (requires 2 ATP)
- energy generation phase (produce: 4 ATP, 2 NADH and 2 pyruvate or 2 lactate)
what does the energy generation phase of glycolysis produce?
4 ATP
2 NADH
2 pyruvate or 2 lactate
does creatine supplementation improve exercise performance?
- increase muscle PC (phosphocreatine) stores
- improves short term high intensity
- increased strength and fat-free mass with resistance training
does creatine supplementation appear to pose health risks?
no
depletion of _____ may limit short-term, high intensity exercise
phosphocreatine
_____ is the conjugated base of lactic acid
lactate
the ionization of lactic acid forms the conjugated base called _____
lactate
_______ id produced in glycolysis
lactic acid
- rapidly disassociates to lactate and H+
what are the two phases of glycolysis
- energy investment phase
2. energy generation phase
what is requires during the energy investment phase
2 ATP
what is produced during the energy generation phase
4 ATP
2 NADH
2 pyruvate or 2 lactate
what are the transport hydrogen’s and associated electrons during aerobic
to mitochondria for ATP generation
what are the transport hydrogen’s and associated electrons during anaerobic
to convert pyruvic acid to lactic acid
what does NAD stand for
nicotinamide adenine dinucleotide
what does FAD stand for
flavin adenine dinucleotide
NADH is the ‘_____’ into the mitochondria
shuttle
NADH produced in glycolysis must be converted back to ____. and how
NAD
- by converting pyruvic acid to lactic acid
- by ‘shuttling’ H+ into the mitochondria
a specific transport system shuttles ___ across the mitochondrial membrane
H+
how do you concert pyruvic acid to lactic acid?
add two H+ to pyruvic acid
skeletal muscles produce _____ that is quickly converted to______
lactic acid
lactate
what are the three ways the muscles can produce ATP using 1 or a combination of
- ATP-PC system
- glycolysis
- oxidative ATP production
what is the aerobic ATP production
krebs cycle( citric acid cycle / oxidative ATP production
what fat is used in aerobic metabolism
triglycerides–> glycerol and fatty acids
fatty acids—> acetyl- CoA (beta-oxidation)
-glycerol is not an important muscle fuel during exercise
what protein is used in aerobic metabolism
- broken down into amino acids
- converted to glucose, pyruvic acid, acetyl-CoA and krebs cycle intermediates
what is an aerobic ATP production
electron transport chain
where does oxidative phosphorylation occur?
mitochondria
during the electron transport chain electrons removed from NADH and FADH are passed along a series of carriers (________) to produce ATP
cytochromes
what does the electron transport chain produce?
each NADH produces 2.5 ATP
each FADH produces 1.5 ATP
what is the chemiosmotic hypothesis of ATP formation
electron transport chain results in pumping of H+ ions across inner mitochondrial membrane (H+ gradient)
-energy released to form ATP as H+ ions diffuse back across the membrane
the H+ from NADH and FADH in the electron transport chain is accepted by ___ to form ____
O2
water
beta oxidation is the process of converting ______ to _______
fatty acids
acetyl- CoA
what enters the krebs cycle?
acetyl-CoA
activated fatty acid ( fatty acyl-CoA) into the mitochondrion, fatty acid ‘chopped’ into _____ fragments forming acetyl-CoA
2 carbon
how many ATP are produces from 1 glucose
32 ATP
