final

Question 1

acid

Answer 1

releases hydrogen ion, can raise H conc.

Question 2

base

Answer 2

combines w hydrogen ion, lower H conc.

Question 3

strong acid

Answer 3

acids that more completely give up H ions = ionize
ex: sulfuric acid

Question 4

strong base

Answer 4

bases that ionize more completely
ex: HCO3-

Question 5

acidosis

Answer 5

hydrogen ion conc. increases, pH declines, acidity of blood increases

Question 6

alkalosis

Answer 6

hydrogen ion conc. decreases, pH increases, solution becomes more basic

Question 7

normal arterial pH

Answer 7

7.4

Question 8

3 contributors to exercise induced muscle acidosis:

Answer 8

1. production of CO2 and carbonic acid(HCO3-) in working skeletal muscles
2. production of lactic acid in working muscles
3. ATP breakdown in working muscles

Question 9

volatile acid

Answer 9

ex: CO2
as gas that can be eliminated by lungs
- exercise adds a volatile acid load on body

Question 10

what type of exercise presents a threat to acid-base disturbances?

Answer 10

high intensity

Question 11

how does changes in muscle pH affect exercise performance?

Answer 11

1. reduces muscle cell’s ability to produce ATP (inhibits enzymes involved in anaerobic and aerobic production of ATP)
2. H ions compete w Ca ions for binding sites on troponin (hinders contractile process)

Question 12

buffer

Answer 12

resists pH change:
removes H ions when H ion conc. increases
releases H ions when H ion conc. decreases

Question 13

2 factors impacting buffer ability:

Answer 13

1. intrinsic physiochemical ability
2. conc. of buffer (the greater, the better)

Question 14

4 major intracellular chemical buffer systems in cytosol of muscle fibers:

Answer 14

1. bicarbonate
2. phosphates
3. cellular proteins ex: histidine
4. histidine - dipeptides ex: carnosine

Question 15

2 primary hydrogen transporters across sarcolemma:

Answer 15

1. sodium-hydrogen exchangers (NHE)
2. monocarboxlate transporters (MCTs)

Question 16

NHE function

Answer 16

move sodium ions into muscle and h ions into interstitial space
(one for one)

Question 17

2 types of MCTs: both do?

Answer 17

1. MCT1
2. MCT4
   mediate cotransport of lactate and hydrogen out of muscle across sarcolemma

Question 18

which type of muscle fiber has a higher intracellular buffering capacity?

Answer 18

fast/ type II

Question 19

3 buffer systems of blood:

Answer 19

1. proteins
2. hemoglobin
3. bicarbonate

Question 20

which blood buffer is important during rest?

Answer 20

hemoglobin:
- high conc. = 6x buffering capacity of proteins
- deoxygenated = better bind to h formed when CO2 enters from tissues

Question 21

most important buffer system in body

Answer 21

bicarbonate
- increased blood bicarbonate conc. = improved exercise performance

Question 22

henderson - hasselbalch equation

Answer 22

describes ability of bicarbonate and carbonic acid to act as buffer system:
- pH of weak acid solution is determined by ratio of conc. of base in solution to conc. of acid
pH= = pKa + log10(Hco3-/h2co3)

Question 23

ratio of bicarbonate to carbonic acid

Answer 23

20 to 1

Question 24

important regulator of blood carbonic acid and pH:

Answer 24

lungs/ respiratory system

Question 25

supplements taken to increase extracellular buffer capacity/ prevent exercise-induced acidosis:

Answer 25

• sodium bicarbonate
• sodium citrate
• beta-alanine

Question 26

principal way kidneys regulate ion conc.

Answer 26

increase or decrease bicarbonate conc.
via excretion
*regulation from tubule
*reacts too slow to be important

Question 27

is muscle or blood pH lower?

Answer 27

muscle by .4-.6 pH units - muscle H ion conc is high, and buffering capacity is lower

Question 28

what does amount of h ions produced during exercise dependent on?

Answer 28

1. exercise intensity
2. amount of muscle mass involved
3. duration of exercise

Question 29

% contribution to cell’s buffering capactity:

Answer 29

1. histine dipeptides = 60%
2. muscle bicarbonate = 20-30%
3. intracellular phosphate groups = 10-20%

Question 30

respiratory compensation

Answer 30

respiratory assistance in buffering lactic acid during exercise - increase alveolar ventilation = reduced blood PCO2

Question 31

first and second line of defence against exercise-induced acidosis

Answer 31

1. buffers in muscle fiber
2. blood buffer systems

Question 32

“blowing off carbon dioxide”

Answer 32

increase in pulmonary during intense exercise assists in eliminating carbonic acid

Question 33

atmospheric pressure

Answer 33

measure of weight of column of air directly over that spot
*greatest at sea level

Question 34

hypoxia

Answer 34

lower PO2 = decreased O2 transport - altitude

Question 35

normoxia

Answer 35

PO2 under sea-level conditions

Question 36

hyperoxia

Answer 36

inspired PO2 is greater than at sea level

Question 37

are short-term anaerobic races affected by low PO2 at altitude

Answer 37

no - O2 transport isn’t limiting performance

Question 38

how does lower air density at altitude affect shorts movements?

Answer 38

less resistance to high speed movements

Question 39

how does altitude impact long distance running?

Answer 39

VO2 max decreases in linear fashion as altitude increases

Question 40

max cardiac output

Answer 40

max HR x max SV

Question 41

what does altitude induced bradycardia suggest?

Answer 41

myocardial hypoxia may trigger slower HR at high altitude, decreasing work and oxygen demand of heart muscle

Question 42

why does VO2 max decrease at a faster rate at higher altitudes?

Answer 42

• effects of desaturation of hemoglobin - moderate
• decrease in max cardiac output - high

Question 43

why do submaximal performances at altitude require higher HR and ventilation responses?

Answer 43

• lower oxygen content of arterial blood
• reduction of # O2 molecules per L of air