Pre Midterm Content Flashcards
Content up to the midterm
True of false: ATP is a limited currency
true
True of false: anabolism is exergonic
false, anabolism is endergonic and catabolism is exergonic
The three types of biological work
mechanical, chemical, transport
do cells store more PCr or ATP
PCr.
Cells store about 4 to 6 times more PCr than ATP
Why do NADH and FADH2 provide energy molecules?
Because they have high energy-transfer potential
what is the respiratory (cytochrome) chain?
the final common pathway where electrons extracted from hydrogen pass to oxygen.
What is the last electron receiver in the electron transport chain?
Oxygen
Each mole of ATP formed from ADP conserves approximately how many kcals of energy?
7 kcals
True or false: Anaerobic glycolysis is fast and aerobic is slow
true.
the word for glycogen break down
glycogenolysis
the word for glycogen synthesis
glycogenesis
What is the name of the insulin dependent transporter in muscle fibers and adipocytes
GLUT 4
What does the Cori Cycle do?
Removes lactate released from active muscles and uses it to replenish glycogen reserves depleted from intense physical activity.
Each Acetyl-CoA entering the citric acid cycle release how many CO2 and how many pairs of H+?
2 CO2
4 Pairs of H+
What are the three components of aerobic metabolism?
Citric acid cycle, electron transport chain, Oxidative phosphorylation.
What is the body’s most plentiful source of energy?
stored fat
What are the two tasks of Free Fatty Acids (FFAs)?
- Re-esterify to form triacylglycerols
- Bind with intramuscular proteins and enter the mitochondria for energy metabolism by action of carnitine acyltransferase located on the inner mitochondrial membrane.
What is deamination and what is the main site where it happens
the removal of nitrogen from an amino acid. happens mainly in the liver.
Skeletal muscles contain enzymes that remove nitrogen from amino acids, what is this process called __________.
Transamination
What does it mean when an amino acid is glucogenic
It means that when it is deaminated it yields pyruvate.
What does it mean when an amino acid is ketogenic?
when deaminated, it yields acetoacetate (intermediate Acetyl-CoA)
What are the 5 conditions under which glycogen depletion can occur?
- Prolonged physical activity (eg. marathon)
- Consecutive days of intense training
- Inadequate energy intake (eg. routinely skipping meals)
- Dietary elimination of carbs (eg. keto)
- Diabetes, which impairs cellular glucose uptake
ATP last for how long?
1-2 sec
What are the three systems of energy provision pathways for ATP production? (chapter 7, p.162-169)
- Immediate energy system
- Short-term energy system
- Long-term energy system
What are the 4 “energy” sources fort he “synthesis” of ATP for muscular work?
- from the breakdown of PCr
- From the adenylate kinase (myokinase) reaction
- From the guanosine triphosphate reaction
- from food
What is the enzyme that catalyzes the breakdown of ATP?
ATPase
What catalyzes the breakdown of PCr?
Creatine kinase
In the Adenylate kinase reaction,
ADP + ADP –> ____________.
ADP + ADP –> ATP + AMP (adenosine monophosphate)
Immediate energy system is the primary energy source for what kind of exercise?
Acute
Strength, power, sprint
True or false?
Immediate energy stores have high rate of energy and high capacity.
False.
High energy rate but LOW capacity
what is the creatine protocol for loading?
approx. 20-30 g/day or 0.30 g/kg body mass/day of Cr over 3-5 days.
What is the creatine protocol for maintenance?
approx. 2-5 g/day or 0.03 g/kg/day for several weeks.
Why is creatine supplementation a bad idea for sports in which you need to make weight?
increased body mass due to retention of total body water.
What are the 3 classifications of carbohydrates?
Monosaccharides
Oligosaccharides
Polysaccharides
define monosaccharide. What are the 3 types?
basic unit of carbohydrate (glucose, fructose, galactose)
Define oligosaccharides, and state the 3 types.
2-10 monosaccharide molecule linkages (sucrose, lactose, maltose)
Define polysaccharide, name the two types.
3 to thousands of monosaccharide molecule linkages (starches and fibers)
What are the 4 main roles of carbs in the body?
- energy source during exercise at all intensities
- protein sparer - helps preserve tissue protein
- metabolic primer - for fat oxidation
- Fuel for CNS - primary fuel for nerve tissue
The body store _____Kcals of carbohydrates.
2000 kcals
muscle stores _____ g of glycogen.
400 g
liver stores ______g of glycogen.
90-100 g
What is the upper limit for glycogen storage on average?
15 g / kg of body weight
What are the 3 lipid groups
simple (triacylglycerols - saturated and unsaturated)
compound (phospholipids and lipoproteins)
derived (cholesterol)
The 4 major function of lipids are:
- energy source and reserve
- Protect vital organs
- thermal insulator
- vitamine carrier and hunger suppressor
True of false
fat serves as the main energy substrate during low intensity exercise.
True
Carbohydrates, primarily muscle glycogen, is the energy source during what intensity exercise
high intensity
Protein is constructed from ____________.
Linked amino acids
Carbohydrate depletion increase the use of fat or protein as a fuel?
Protein
The recommended amount of daily protein for both men and women is _______ g per Kg of body mass.
0.8 g / kg body mass
What are the two major functions of anaerobic (rapid) glycolysis / glycogenolysis?
- synthesis of ATP
2. generation of pyruvate
where does glycolysis / glycogenolysis take place?
sarcoplasm
The 3 stages of glycolysis are:
- the activation or priming stage
- The splitting stage
- Oxidizing and reducing stage
Stage 1 of glycolysis (activation stage) is what kind of reaction and is catalyzed by what?
endergonic reaction (splitting of one ATP) catalyzed by hexokinase
In glycolysis, you skip the first step and save one ATP if _________ is the substrate.
Glycogen
What is the role of phosphofructokinase in activation step 2 of glycolysis?
It is a rate limiting enzyme and determines the speed if the pathway
The rate of stage 3 of glycolysis is dependent on the availability of ________.
NAD+
What stage of glycolysis/glycogenolysis generates the first 2 ATP in the pathway
stage 3, oxidation/reduction
what are the two possible fates of pyruvate?
- entry into mitochondria to be oxidized
2. Be reduces to lactate
what would happen if you didn’t have lactate during glycolysis?
you wouldn’t have any NAD+ so the whole process would shut down.
pyruvate produced from glycolysis can enter the mitochondria via _________.
A protein channel
Once in the mitochondria, pyruvate converts to _______ which enters _______.
acetyl CoA which enter the krebs (citric acid cycle)
what are the two general locations within muscle fiber where you can find mitochondria?
Intermyofibrillar And subsarcolema (inside cell membrane)
What are the main products of the krebs cycle
NADh+H+ and FAFH2
What are the by-products of the krebs cycle
CO2 and H2O
What does each acetyl CoA generate from one Krebs cycle?
3 NADH
1 ATP
1 FADH2
2 CO2
In the electron transport chain which of the following bypasses complex I?
FADH2
NADH + H+
FADH2
which of the following results in more ATP in the electron transport chain?
FADH2
NADH + H+
NADH + H+
which complex is thought to be rate limiting in Electron Transport Chain?
Cytochrome Oxidase step (Complex IV)
5 steps of the transportation of FFAs in order for their energy to be obtained.
- from the blood
- across the cell membrane
- through the cytosol
- into the mitochondria
- into the mitochondrial matrix
Do fats need CHO to be fully metabolized?
Yes, they need the pyruvate to get some oxaloacetate
what is the rate limiting enzyme in the krebs cycle?
isocitrate dehydrogenase
Does slow or fast twitch muscle have more mitochondria?
Slow twitch
What are the y and x variables of the power duration curve?
Y: Intensity
X: Duration
Can you change your power duration curve with training?
Yes
The power/duration curve directly reflects the body’s capacity to transfer _________ energy into _________ energy.
Chemical energy into mechanical energy
What is bioenergetics?
The transformation of energy in the human body.
What are the three types of energies that we are primarily concerned with in physiology?
mechanical
chemical
heat
What is thermodynamics?
The study of relationships between heat energy and other forms of energy.
Endergonic reaction absorb or release energy?
absorb
Exergonic reaction absorb or release energy?
release
Total energy expenditure of body at rest = _________ + _________
cellular work done + amount of heat produced
True or false. ATP is the only source of energy that can be used by muscle for contraction.
True
Total energy expenditure of body during exercise = _________ + _________
mechanical work done + heat produced
What is the name of the tool used to estimate the heat equivalence of food.
bomb calorimeter
What is the Hill relationship?
When energy is metabolized to re-synthesize ATP to do muscular work, heat is given off, and O2 is consumed in a proportional amount
what is the O2, CO2, and N2 percentages in the air?
O2 = 20.93% CO2 = 0.03% N2 = 79.04%
what is the O2, CO2, and N2 percentages when you exhale in an ergometer?
O2 = about 15-16% CO2 = about 4-5% N2 = about 79.04% (assume N2 doesn't change)
What does STPD stand for?
standard Temperature, Pressure, Dry
What is the respiratory quotient
the ratio of CO2 to O2 (CO2/O2)
The Respiratory quotient for fat metabolism is greater or less than 1?
<1
Respiratory quotient for protein is not used often, but what is it’s approximation?
0.82
What is the respiratory quotient for CHO metabolism?
1.0
What is the difference between RQ and RER?
RQ is the respiratory quotient and is the ratio of CO2 to O2 in the cell.
RER is the respiratory exchange ratio and is the ratio of VCO2 to VO2 measured at the lung level.
RER ranges between _________ and ________ depending on the intensity of the exercise.
0.70 and 1.0
True or False. RER cannot exceed 1.0 at any time.
false.
it can at high intensity exercise.
what is the difference between BMR and RMR?
RMR is measured under less stringent laboratory conditions.
for most people RMR ranges between _______ Kcal/min
0.8 - 1.4 kcal/min
How much lower is BMR in females compared to males of the same age?
5-10%
Age related drop in BMR is about ___% after about age ____.
about 2% after about age 40
what kind of exercise training is best for promoting increases in RMR and calorie burning for better body weight management?
a combination of strength and endurance.
Obligatory thermogenesis
energy required to digest, absorb, and assimilate food nutrients.
facultative thermogenesis
activation of sympathetic nervous system and its stimulating influence on metabolism.
facultative thermogenesis reaches maximum about how long after a meal?
1 hour
Efficiency
the relationship between amount of work done and total energy required to do the work expressed as a percentage
Economy
oxygen consumption required to complete a certain amount of work
What is the difference between gross and net efficiency?
Gross includes resting energy expenditure, Net is when RMR is subtracted from exercise energy expenditure
delta efficiency
the ratio between the change work and energy expenditure measure across two different exercise intensities.
What are the 7 general factors influencing efficiency and economy
- age
- fiber type / anatomy
- Body mass
- Skill/technique/sport
- fitness level/training
- environmental conditions
- engineering
one met is equivalent to…
1 Kcal/kg of body mass/hour
O2 deficit
period of time at the start of exercise during which aerobic metabolism is adjusting to meet the metabolic demands
EPOC had how many phases? what are they?
2 phases fast component (immediately after exercise lasting 30 sec to several minutes). Slow component (after fast component lasting several minutes to hours)
What happens in the fast component of EPOC?
rapid drop in VO2, Ve and HR.
rapid restoration of ATP and PCr
What happens in slow component of EPOC?
Slower decline in VO2, Ve and HR but above rest. Energy returns to state of homeostasis
What type of energy is used to restore ATP and PCr?
aerobic
How long does it take for the nervous system to recover completely?
8-12 minutes
How long does it take for the nervous system to recover the majority of it “excitability”?
1-6 minutes
Acid
A chemical compound that donates a H+ in solution
Base
A chemical compound that gives us and OH- in solution
range of resting muscle pH
6.90-7.10 (about neutral)
range of resting blood pH
7.40-7.45 (slightly alkaline)
true or false?
Lactate is a consequence of anaerobic glycolysis and is not the cause for muscle acidosis.
true
What is the lactate shuffle?
it refers to the formation of lactate in one cell compartment and used in another (within the same muscle between muscle fibers or in other organs) as a “fuel”.
True or false.
lactate inhibits muscle contraction
false.
it doesn’t inhibit muscle contraction and therefore it also doesn’t directly contribute to fatigue
Why is a trained person able to delay the blood lactate/anaerobic threshold?
They have more mitochondria in their cells.
Where does H+ come from during anaerobic exercise? give the 2 primary sources.
- a net production of H+ from intermediary compounds in glycolysis for each glucose molecule.
- H+ release during the hydrolysis of ATP
Is a decrease in pH associated with a decrease in muscle force production? Does it contribute to muscle fatigue?
yes and yes
what is the main buffer of the body?
Bicarbonate Ions
In breathing, Exchange I is between _______ and _______.
atmosphere and lungs
In breathing, Exchange II is between _______ and _______.
lungs and blood
In breathing, Exchange III is between _______ and _______. This is called __________.
blood and cells
called cellular respiration
Gas volumes are affected by _______, _________, and _________.
temperature, humidity and water vapor
