Skeletal Muscle Physiology and ATP Production

These flashcards cover key terms and concepts related to skeletal muscle physiology, ATP production pathways, muscle fiber types, and the effects of exercise on muscle.

ATP

Adenosine triphosphate, the primary energy carrier in cells that powers various processes, including muscle contraction.

Muscle Contraction

The process where muscle fibers shorten and generate force, requiring ATP for myosin-actin interaction.

Creatine Phosphate Pathway

A quick source of ATP generated by the transfer of a phosphate group from creatine phosphate to ADP.

Anaerobic Pathway

An ATP production method that does not require oxygen and primarily uses glucose, yielding 2 ATP per glucose.

Aerobic Respiration

A process that requires oxygen to produce ATP, yielding 30-32 ATP per glucose through metabolic pathways.

Lactic Acid Fermentation

An anaerobic process where glucose is converted into lactic acid and ATP when oxygen is scarce.

Muscle Fiber Types

Categorized by contraction speed and ATP production pathway; includes slow oxidative, fast oxidative, and fast glycolytic fibers.

Fatigue

The physiological inability of muscles to contract or respond to stimuli, different from central fatigue.

Glycogen

A stored form of glucose found in the liver and muscles that can be broken down to provide energy.

Myoglobin

An oxygen-binding protein found in muscle cells, higher amounts are present in slow oxidative fibers, aiding in aerobic respiration.

Acidosis

A condition resulting from increased levels of lactic acid or ketones, leading to decreased pH and potential inhibition of metabolic processes.

Hypertrophy

The increase in the size of muscle fibers due to growth and increased synthesis of contractile proteins.

Atrophy

The decrease in muscle mass or size due to disuse or injury, which can be reversible if nerve supply is intact.

Calcium Ion (Ca2+)

An essential ion for muscle contraction, its release from the sarcoplasmic reticulum initiates the contraction process.

Sarcoplasmic Reticulum

An organelle in muscle cells that stores calcium ions and releases them to trigger muscle contraction.

Oxidative Fibers

Muscle fibers that primarily rely on aerobic cellular respiration for ATP production.

Glycolytic Fibers

Muscle fibers that primarily rely on anaerobic glycolysis for ATP production.