EXAM 3: Inflammatory and Degenerative Conditions & Muscle Fiber Microanatomy

Vocabulary flashcards covering key terms and definitions from the lecture on inflammatory and degenerative conditions, and muscle fiber microanatomy.

Rheumatoid arthritis (RA)

A chronic, inflammatory, autoimmune disease of unknown cause that occurs when the immune system attacks its own cells.

Symptoms of RA

Joint pain and swelling (usually bilateral), anemia, osteoporosis, muscle weakness, and cardiovascular problems.

Sarcolemma

The plasma membrane of a muscle fiber.

Sarcoplasm

The cytoplasm of a muscle fiber, containing glycosomes for glycogen storage and myoglobin for O2 storage.

Myofibrils

Long, cylindrical structures within muscle fibers composed of myofilaments responsible for muscle contraction.

Elastic filament

A filament composed of protein titin that holds thick filaments in place and helps recoil after being stretched.

Dystrophin

A protein that links thin filaments to the proteins of the sarcolemma.

Sarcoplasmic reticulum

A network of smooth endoplasmic reticulum tubules that surround each myofibril, regulating intracellular calcium levels.

Synaptic cleft

The gel-filled space separating the axon terminal and muscle fiber, where neurotransmitters are released.

Acetylcholine (ACh)

A neurotransmitter stored in synaptic vesicles that transmits nerve impulses to muscles.

Neuromuscular junction (NMJ)

The junction formed by the axon terminals, synaptic cleft, and junctional folds that transmits signals from nerves to muscles.