Exam 3 Review:  Chapter 09:  Muscle Cell/Fiber Physiology

aerobic - (1) A process depending on free oxygen or air, e.g., aerobic glycolysis; (2) involving or improving oxygen consumption by the body, e.g., aerobic exercise; (3) living or occurring only in the presence of oxygen, e.g., aerobic bacteria.

cellular respiration - The series of metabolic processes, located in the cytoplasm and in the mitochondria, by which living cells produce ATP energy through the oxidation of organic nutrient substances.

myoglobin - A single-polypeptide-chain, iron-containing, oxygen-storing protein found in striated muscle fibers, structurally similar to a single subunit of hemoglobin and having a higher affinity for oxygen than hemoglobin of the blood.

anaerobic - (1) A process not depending on free oxygen or air, e.g., anaerobic glycolysis; (2)  living or occurring only in the absence of oxygen, e.g., anaerobic bacteria.

glycolysis - An ATP-generating oxidative metabolic process that occurs in the cytoplasm of nearly all living cells in which glucose and other sugars are converted in a series of enzyme-catalyzed steps to pyruvic acid; these reactions are coupled to reactions which add energetic phosphate groups to ADP to yield ATP; technically, glycolysis is an anaerobic process because it does not require oxygen, though it can occur while the cytoplasm is experiencing an aerobic condition.  See additional material on glycolysis in the Exam 4 Review:  Chapter 24:  General Metabolism Terms.

lactic acid - The 3-carbon end product of anaerobic glycolysis (fermentation) which must leave the muscle cell and travel to the liver, heart, or kidneys, which can use the molecule as a nutrient source for additional energy production; the liver is also capable of reconverting this molecule into glucose or glycogen.

creatine phosphate - The small organic compound found in muscle cells which serves as a molecular storage depot for chemical energy in the form of high energy phosphate groups; when needed this compound transfers a high energy phosphate group to ADP to form ATP.

oxygen debt - A cumulative deficit of oxygen resulting from intense exercise; the deficit must be made up when the body returns to rest; muscle tissue stored oxygen, ATP, creatine phosphate, and glycogen levels, and normal pH must be restored to "pay the debt."

muscle fatigue - The decreased capacity or complete inability of a muscle to function normally because of excessive stimulation or prolonged exertion.

red muscle fiber - The simple descriptive name given to the two types of oxidative skeletal muscle fibers (as opposed to the glycolytic fibers); these two types of cells have a high myoglobin content, a low to intermediate glycogen content, and tend to contract and to fatigue relatively slowly.

white muscle fiber - The simple descriptive name given to the two types of  glycolytic skeletal muscle fibers (as opposed to the oxidative fibers); these two types of cells have a low myoglobin content, an intermediate to high glycogen content, and tend to contract and to fatigue relatively quickly.

List:

8. Three types of muscle metabolism for ATP production and how each type operates biochemically and how each type is suited to different durations (time frames) of muscle activity.