Metabolism and Hormones (Exams 1 &2) Flashcards
define metabolism
all chemical reactions in the body
catabolism
breakdown
anabolism
build up
1st law of thermodynamics
energy is neither created or destroyed
2nd law of thermodynamics
processes goes from higher order to lesser order
how much energy in the body is released as heat?
60-70%
advantages and disadvantages to using carbs
fast, readily available, easy to use for energy, used for aerobic and anaerobic activities
must be stored with H2O, takes lots of space
advantages and disadvantages to fats
lots of energy yeilded, long term duration activities, slower transport to mm and requires O2 so cant be used for anaerobic
why can’t proteins be used for much energy?
bc u can’t oxidize nitrogen
whats the key to using proteins as energy?
must convert the AA to PEP through gluconeogenesis- however, this costs a lot of ATP
stored ATP breaks down through what mechanism?
hydrolysis and ATPase no O2 required
what is the ATP-PCR system used for?
explosive quick energy,
anaerobic, 5-15 seconds
produces 1 mol ATP and 1 mol PCr
what is the formula for the ATP PCr system and what enzyme works in the system
ADP+PCR–>ATP +Cr
creatine kinase
finish this formula:
ADP+ ADP–>
ATP and AMP (via adenylate kinase)
3 ways to make ATP IMMEDIATELY!
1) from ATP, ATP+H2O(APTase)–> ADP+Pi
2) PCr, ADP+PCr (creatine kinase) –>ATP +Cr
3) ADP, ADP+ADP (adenylate kinase) –> ATP +AMP
Where does glycolysis occur?
in the cytosol
is glycolysis aerobic or anaerobic?
anaerobic
what is glucose broken down into (glucose is in the blood)
broken down into 2,3 carbon sugars called pyruvic acid
where does pyruvic acid go after its broken down from glucose
2 choices:
if there is oxy, it goes into the KREBS cycle.
if there is no oxy, it becomes lactic acid
where does Krebs cycle occur?
in the mitochondria
how does pyruvic acid get from the cytosol where it was broken down from glucose, into the mitochondria where krebs ocurs?
joins with oxy to become acetyl coA and be shuttled accross the membrane
what does lactic acid yield?
lactic acid breaks down into lactate + H+, the lactate goes into the krebs cycle and the H+ goes into PCr+ADP+ H+–>APT +PCr
what does lactate dehydrogenase do?
converts pyruvic acid into lactate which can then go into the Krebs cycle
whats the cori cycle, where does it occur and when do u use it?
creases glucose from lactate in the liver with the use of 6 ATP (very expensive) only use to maintain blood glucose if u are fasting
describe ETC
H+ from the end of glycolysis and krebs join with NAD/FAD to be NADH and FADH2, the the H+ goes thru the ETC and ATP+ H2O comes out
each NADH yields how many ATP?
3
each FADH2 yields how many ATP?
2
all the way from glycolysis through ETC yields how many ATP?
38 from glucose
39 from glycogen
how do the FFA floating in the blood stream get into krebs?
acetyl CoA picks em up and takes em into the mitochondria
1 16 Carbon fat results in…
8 acetyl CoA–>
7 NADH
7 FADH2
= 31 ATP-2 for activation= grand total of 129 ATP
What makes a person high risk for exercise testing?
known CV, pulmonary or metabolic disease
what are the precautions for high risk exercise testing?
need physician present for max or sub max
What makes a person moderate risk for exercise testing?
Asymptomatic with 2 or more risk factors
what precautions must be taken when a person has moderate risk for exercise testing?
physician recommended to be present for max exercise testing only
what makes a person low risk for ex. testing?
asymptomatic with only 1 or fewer risk factors.
list all the risk factors…
1) age (M-45,W-55)
2) fam. hx (1st degree relative with MI or bypass before 55 (M) or 65 (W))
3) smoking- current or stopped within last month
4) sedentary lifestyle- less than 30 min/day 3 times a week for the last 3 months
5) obesity- BMI over 30
6) hypertension- 140/90
7) dyslipidemia- on cholesteral meds or LDL>130 mg/dL, HDL <40 mg/dL
8) pre diabetes- fasting glucose of 100 mg/dL or more, or Oral glucose tolerance test between 140-200
what fasting glucose test score is positive for diabetes?
126 or greater
what OGTT is positive for diabetes
over 200
waist circumference
women
very low risk: 110 cm
waist circumference
Men
very low risk: 120 cm
receptors for water soluble hormones vs. steroid hormones
water soluble= located on cell membrane
steroids (fat sol)= located in cytoplasm or in nucleus
steroid hormones are produced by…?
produced by adrenal cortex and gonads,
examples of steroid hormones
cortisol, testosterone, estradiol
define hormone
substance secreted by a specialized gland into the blood, carried to a target tissue and binds to a specifi receptor to exert biological effects
non steroid hormones
amino acid derived: thyroxine, epinephrine, norepinephrine
anterior pituitary is contolled by what? releases what?
hypothalamus; growth hormone
3 thyroid hormones
> calcitonin-
T3
T4
what does calcitonin do?
reduces blood Ca levels, inhibits bone resorption (bones releasing Ca into blood)
what does T3/T4 do?
increases cellular metabolism, inc. HR and contractility, promotes uptake of glucose, enhance glycolysis and gluconeogenesis, enhance lipid mobilization
(it upregulates everything u need in flight!)
what does the adrenal medualla produce?
epinephrine and norepinephrine
what do epi and norepi do?
inc. HR and contraction strength, BP and RR
inc. metabolic rates
releases glucose and FFA intoblood
vasodilation
inc. blood to skin for temp control
how are epi and norepi affected by exercise?
both increase, norepi increases first and takes several hours to return to normal, epi comes in later and goes back to norm w/in mins
what does the adrenal cortex produce?
glucocorticoids
corticosteriods : cortisol
mineralcorticoids:aldosteron
what is the job of a glucocorticoid?
adapt to external changes and stress, maintain consistent levels of glucose with and without food
cortisol?
stimulates gluconeogenesis, increases FFA mobilization, stim. protein metab., depresses immune reactions, vasoconstriction
mineralcorticoids, aldosterone and ADH
maintain electrolyte levels
aldosterone: stim. kidneys to retain Na (and therefore retain water) while excreting K+
when is aldosterone released?
decreased plasma Na+, decreased blood volume, decreased BP or inc. K+
pancreas hormones
insulin: released when blood glucose high
glucagon: released when blood glucose is low
posterior pituitary is triggered by what and produces what hormone?
triggered by hypothalamus and produces ADH
what does ADH do?
promotes water conservation
direct calorimetry
measures heat
-expensive
indirect calorimetry
measures O2/CO2
-common method
Formula to get from METS to lb. of fat
take METS x 3.5=relative VO2 (ml/kg/min), then x bw in kg to get absolute VO2 in (ml/min), then divide by 1000 to get absolute VO2 in (L/min), then x5 to get Kcal/min, then x total number of mins to get total kcals then divide by 3500 to get lb. of fat.
whats the target % of max HR to be in fat burning
40-60%
RER
respiratory exchange ratio: V CO2/ V O2
RER fats, mixed, carbs
- 65- fats (more O2 (beta ox. than CO2 glycolysis)
- 80- mixed fuel source
- 05- carbs (more CO2 glycolysis than O2 b oxidation)
what happens at the lactate threshold
glycogen breakdown slows (stops PFK), inhibits glycogen phosphorylase, decreased FFA mob., dec. mm contractions–>body’s way of telling u to STOP!
what transmits AP from sarcolemma to deep into mm fiber, close to the SR
T tubules
what does the SR do?
stores, releases and reuptakes calcium
Z line to Z line=
one sarcomere
I band
thin filaments (actin)
A band
overlap of filaments
H band
thick filaments (myosin)
M band
midline
what do the diff. types of troponin do?
C,T, I
C= binds calcium T= binds troponin to tropomyosin I= inhibitory on tropomyosin when no Ca available
what happens when calcium binds to troponin?
Ca binds to troponin and moves tropomyosin out of the way so that myosin can bind to the actin
largest protein in the body
titan
nebulin
5% of protein in body, measures length of think filament
myosin heavy chain
heads contain ATP and active binding sites
myosin light chain
regulates speed
thalamus=
sensory input for motor control (except smell)
hypothalamus=
maintains homeostasis, internal environments
-BP, HR, contractility, breathing, digestion, body temp, fluids, endocrine control, emotions, sleep/wake, food/thirst
cerebellum
rapid movements
compares intended act. with actual results and makes corrections
recieves visual input
smooths out the jerks in movements
brain stem
autonomic regulation (resp. and CV) reticular formation skeletal mm fxn maintain mm tone consciousness pain control with opiates
stroke population exercise program
aerobic 20-60 min, 3-5 days/week at 40-70% VO2 max, use RPE
strengthening: 2-3 days/week 3 sets of 8-12 reps
PD exercise program
aerobic 3/week 60 min, 60-80% max HR
walking 20-30 min, 4-6 x/day
strength 3x/week 1 set of 8-12 reps
flexibility:1-3x/week
MS exercise program
aerobic: 3x/week, 30 min,60-85% HR or 50-70% VO2 max
strength: opp days of endurance
flex: 5-7 days/week
