Test One Flashcards

Question

Know the utility of measuring citrate synthase activity; what is the difference in CS activity in type IIa vs. IIx fibers? Effect of exercise intensity?

Answer 1

CS is a marker of mitochondrial oxidative capacity and a rate-limiting enzyme in Krebs cycle that catalyzes synthesis of citrate, and is found in mitochondria. It will increase speed of Krebs, so increase ATP production. CS increases in type IIa fiber with all training intensities, but duration has no impact in type IIa fibers with CS levels. However, with type IIx longer duration and higher intensity is required to increase CS levels.

Answer 2

Aerobic training will lower oxygen deficit because there is more mitochondria. This makes the body more sensitivity to the energy level making it faster to make ATP at a lower concentration of ADP. [ADP] stimulates mitochondrial ATP production. Increased mitochondrial numbers following training, thus, lowering [ADP] needed to increase ATP production and VO2. VO2 is at same but at lower concentraton of ADP. More energy requirement can be met by aerobic ATP production at the onset of exercise so there is a faster rise in VO2 curve and steady state is reached earlier. Results in less lactate and H+ formation and less PC depletion.

Answer 3

Aerobic training is considered “carb-sparing” because there is increased use of fat and less plasma glucose and glycogen. Carbohydrates are made up of glucose molecules. This is because this kind of training uses more oxygen, and fatty acids do not go through glycolysis, but they go through the aerobic process beta-oxidation. It will use more transport of FFA into the muscles through increased capillary density and increased FABP and FAT. Transport of FFA from cytoplasm to the mitochondria increases mitochondrial number so there is more mitochondrial oxidation of FFA since increased enzymes of beta-oxidation. Also, increased capillary density results in slower blood flow in muscle and increased FFA transporters that cause increased uptake of FFA, which will cause the body to increase FFA use and spare plasma glucose. Mitochondrial number increase causes increase in fatty acid cycle enzymes and carnitine transferase that will increase FFA use and spare plasma glucose.

Answer 4

Well-trained endurance mofo’s experience hypoxemia because at near-max work they have decreased PO2 of 30-40 mm Hg. This is due to ventilation/perfusion mismatch and short RBC transit time in pulmonary capillary due to high Cardiac Output. So the blood is being ejected very quickly causing less ability to extract oxygen.

Answer 5

From rest to exercise, at the onset of constant load submax exercise: Initially, ventilation increases rapidly and then a slower rise toward steady state happens. PO2 and PCO2 are relatively unchanged and going to be maintained by increasing ventilation, and slight decrease in PO2 and increase PCO2 then normalize occurs while ventilation gradually increase until steady state since ventilation is catching up metabolism. In hot environment, during prolonged submax exercise (long duration, steady state), ventilation tends to drift upward (slight increase) because of increase in blood temperature affects respiratory control center (trying to get heat out of body). Also, there is little change in PCO2 and higher ventilation is not due to increased PCO2, but due to higher body temp, way of body cooling down. Untrained person incremental ventilation is linear increase up to approx. 50-75% vo2max (linear increase ventilation), and afterwards there is an exponential increase beyond this point, and this is point is called Ventilatory Threshold (Tvent), or the inflection point where VE/V increases exponentially. Unlike, trained people, untrained people has maintained within 10-12 mm Hg of resting values (they don’t get hypoxemia). Trained person incremental: Ventilation = Tvent happens at higher % VO2max since they are better trained. The big difference between trained and untrained is P02. Decrease of 30 to 40 mm Hg at near-maximal work so there is a higher decrease in PO2, resulting in hypoxemia.

Answer 6

CO2+H20 ←Carbonic Anhydrase→ H2CO3 (carbonic acid) ← → H+ + HCO3- To the lungs (left) To the muscles right At the tissue, CO2 leaves into RBC (passes through membranes) and becomes Carbonic Acid, which dissociates rapidly in an aqueous solution to form bicarbonate (HCO3-). Then, H+ binds to Hb in red blood cell and then HCO3- diffuses out of RBC in plasma, and Cl- diffuses into RBC to take bicarbonates spot at the negative stabilizing the cell (Cl shift/ hamburger). @ lung, oxygen binds to Hb and drives off H+ causing bicarbonate to come back into cell. Thus, rxn reverses to release CO2. (cell is impermeable to H+) Gettting rid of H+ makes acidic condition thus go away.

Answer 7

(Tissues/left) Deoxyhemoglobin + O2 ←-→ Oxyhemoglobin (at lungs/ right) Bohr Effect: anything that impacts affinity of Hb- o2; favors offloading of O2 to the tissues. This is good in tissues since it will increase O2 to tissues, but bad in lungs because it can pick it up. - Increased Temp= lowers Hb-o2 affinity, resulting in a rightward shift of the curve - Decreased pH/ Increased Acidity: lowers Hb-o2 affinity, resulting in a rightward shift of the curve - This increases PO2 of blood and more available for tissues.

Answer 8

Mb: shuttles O2 from the cell membrane into the mitochondria, and has higher affinity for O2 than Hb even at low PO2, which allows Mb to store o2 and continue delievery to mitochondria, so O2 reserve for muscle

Answer 9

V/Q indicates matching of blood flow to ventilation where ideal is 1.0. The apex of lung (top of lung) is Underperfused because of GRAVITY, and the ration will be greater than 1.0 because perfusion (Q) is smaller value which will make a whole number greater than. At the base (bottom) of lung, it is overperfused (GRAVITY IS WHY) because perfusion Q is greater value and since it is denominator is make ratio less than 1. However, during light exercise, it improves V/Q ratio and can equalize, but hard exercise results in V/Q inequality because body is close to hyperventilation (ventilation more than perfusion).

Answer 10

VC= Vital Capacity, which is the maximum amount of gas that can be expired after maximal inhalation/inspirations. Testing in spirometry. FEV1: Forced Expiratory Volume-1 is the volume of air expired in one second during maximal expiration, and is part of VC. Tested in Spirometer test. Most air is exhaled in first second of VC. FEV1/VC ratio: determines if person has healthy pulmonary system. RV= Residual Volume, which is the volume remaining in the lungs after maximum expiration/ exhalation. Prevents lung collapse. TLC: Total Lung Capacity: Amount of gas in the lungs after a maximum inhalation/ inspiration Know % of the air components; how Fick’s law of diffusion determines gas diffusion rate V gas= A/T x D x (P1-P2)

Answer 11

V or Ve is pulmonary ventilation/ minute ventilation, which is the movement of air in or out of the lungs per minute. Can be calculated by: V= VT X f or V=VA+ VD VT: tidal volume: amount of air moved per breath (inspiration and expiration) f = breathing frequency= # of breaths/ min VA= Alveolar Ventilation; the volume of air that reaches the respiratory zone (where alveoli and alveolar sacs are located) VD: Dead-space ventilation (VD) that is the volume of air remaining in the conducting zone (trachea, secondary and tertiary bronchioles)

Answer 12

Asthma: narrowing of the airways bronchospasm, which causes increased work of breathing and dyspnea (shortness of breath). There are many potential causes. Another form is exercise-induced asthma, which happens during or right after exercise (this may impair performance). Chronic Obstructive Pulmonary Disorder/ Disease (COPD): increased airway resistance due to constant airway narrowing and decreased expiratory airflow. 2 Lung diseases that make up COPD: 1.) Chronic bronchitis- inflammation of bronchiole tube that causes excessive mucus that blocks the airway resulting little air in and out (increases R). 2.) Emphysema- airway collapse and increased resistance manifested in bronchi tubes and alveoli sacs, and requires supplemental oxygen just to get little o2 in. A person reaching their VO2max when just walking can exemplify this condition, and smoking is a direct cause. Both conditions lead to dyspnea (shortness of breath) and may interfere with exercise and activities of daily living.

Answer 13

Pressure difference between 2 ends of the air way (alveoli sacs where gas exchange occurs) and resistance of the airways. The formula is: P1-P2/ R= Air flow

Answer 14

During inhalation, the diaphragm pushes downward and ribs lift outward. Volume of lungs increases and intrapulmonary pressure decreases. During expiration, diaphragm relaxes, ribs pulled downward, volume of lungs decrease and intrapulmonary pressure increases. (Boyle’s law)

Answer 15

Pulmonary respiration is ventilation and exchange of oxygen and carbon dioxide in the lungs Cellular respiration is oxygen and co2 production by the tissues

Answer 16

``` Ventilation= mechanical process of moving air into and out of lungs Diffusion= molecules move via concentration gradient ```

Answer 17

Muscular strength is maimal force a mucle or muscle group can generate such as 1RM. Involves high resistance about 2-10 RM. Muscluar endurance increases ability to make repeated contractions against a submax load. It is high rep, low weight/R, RM 20+

Answer 18

Increased mitochondria causes less carb use, causing less pyruvate formed, thus, less lactate formed. More fatty acid acids are mobilized so more type one fibers are used, which causes less ATP hydrolyzed so less H+ made to make less acidic condition so blood pH is maintained better, body is working more efficiently with type one fibers. Also, it makes more lactate removable via nonworking muscle, liver, and kidneys. Lactate will be made energy via gluconeogenesis in liver called Cori Cycle to make glucose. Also, increased capillary density causes muscle to extract same o2 with lower blood flow. There is then redistribution of blood flow to liver and kidney, which increases lactate removal. Redistribution of blood flow: Increased Q causes increased blood flow in liver which causes increased lactate removal so lactate in blood decreases. Also, increased Q will cause decrease blood velocity resulting in more O2 extraction in the working muscle resulting in decreased lactate production so less lactate in the blood.

Test One Flashcards

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