Muscle cell energy sources

Two major types of muscle fibers are found in humans white (anaerobic) and red (aerobic). The former are particularly used in sprints and the latter in prolonged aerobic exercise. During a sprint, muscle uses creatine phosphate and glycolysis as energy sources in the marathon, oxidation of fatty acids is of major importance during the later phases. Nonmuscle cells perform various types of mechanical work carried out by the structures constituting the cytoskeleton. These strucmres include actin filaments (microfilaments), micrombules (composed primarily of a- mbulin and p-mbulin), and intermediate filaments. The latter include keratins, vimentin-like proteins, neurofilaments, and lamins. 

Phosphorus A non-metallic element that is found in the blood, muscles, nevers, bones, and teeth, and is a component of adenosine triphosphate (ATP the primary energy source for the body s cells.) [nih]... 

During the absorptive state, the heart and neural tissue mainly use glucose as an energy source, but they are unable to establish any substantial energy stores. Heart muscle cells are in a sense omnivorous, as they can also use other substances to produce energy (fatty... 

The shaft and rings at the base of the flagellum make up a rotary motor that has been called a "proton turbine." Protons ejected by electron transfer flow back into the cell through the turbine, causing rotation of the shaft of the flagellum. This motion differs fundamentally from the motion of muscle and of eukaryotic flagella and cilia, for which ATP hydrolysis is the energy source. 

Muscle metabolizes glucose to lactic acid during exercise. Red blood cells depend upon anaerobic glycolysis for their energy source. 

In mammalian cells, glucose is the most abundant carbohydrate energy source. It is metabolized in all cells as a glycolytic fuel and is stored in liver and muscle as the polymer glycogen. But certain cells have the enzymes to catalyze the synthesis of glucose under certain conditions. The requirements are (1) the availability of specific carbon skeletons (carbon backbone structures of various types), (2) energy, in the form of ATP, necessary to accomplish the sequence of reactions, and (3) the enzymes to catalyze reactions of the sequence. 

Glucose (C6H12O6) Glycogen A monosaccharide providing the cells with an energy source. A polysaccharide made up of chains of glucose molecules. It is stored mainly in the liver and muscles. It is an energy store for cells. 

Chylomicrons are produced from dietary fat by the removal of resynthesised triglycerides from the mucosal cells of the small intestine into the intestinal lumen. These then enter the circulation via the thoracic dncts in the lymphatic system and enter into the subclavian veins, where triglyceride content is reduced by the action of lipoprotein lipases (LPL) on capillary endothelial surfaces in skeletal muscle and fat. The free fatty acids (FFA) from the triglycerides are used by the tissues as an energy source or stored as triglycerides. The chylomicron remnants, stripped of triglyceride and therefore denser, are then taken up by the liver by LDL receptor-mediated endocytosis, thereby delivering cholesterol to the liver. 

During starvation muscle activity decreases, and muscle protein is broken down to provide a carbon source for the liver production of glucose via gluconeogenesis. Which of the following amino acids remains in the muscle cell to provide a source of energy for the muscle ... 

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