Chapter 10 Flashcards
What are the three types of muscle tissue?
Skeletal muscle, Cardiac muscle, Smooth muscle.
What is excitability in muscle cells?
Responsiveness of muscle cells.
What is contractility?
Ability of muscle cells to shorten.
What is extensibility?
Ability of muscle cells to stretch.
What is elasticity in muscle cells?
Ability of muscle cells to recoil.
What are the functions of skeletal muscle?
Producing movement, maintaining posture and body position, supporting soft tissues, guarding body entrances and exits, maintaining body temperature, storing nutrients.
What do skeletal muscles contain?
Skeletal muscle tissue (primarily), connective tissues, blood vessels, and nerves.
What is the epimysium?
Layer of collagen fibers that surrounds the entire muscle, connected to deep fascia, separating muscle from surrounding tissues and organs.
What is the perimysium?
Divides the skeletal muscle into series of compartments, surrounds muscle fiber bundles (fascicles), contains collagen fibers, elastic fibers, blood vessels, and nerves.
What is the endomysium?
Surrounds individual muscle cells (muscle fibers), contains capillary networks, myosatellite cells, and nerve fibers.
What is a tendon?
Bundle formed by collagen fibers of epimysium, perimysium, and endomysium at the ends of muscles to attach skeletal muscles to bones.
What is an aponeurosis?
Broad sheet formed by collagen fibers of epimysium, perimysium, and endomysium at the ends of muscles to attach skeletal muscles to bones.
What are skeletal muscle fibers?
Are enormous compared to other cells, contain hundreds of nuclei, develop by fusion of embryonic cells (myoblasts), and are known as striated muscle cells due to striations.
What is a sarcomere?
Repeating functional units formed by the arrangement of thin (actin) and thick (myosin) filaments in skeletal muscle fibers.
What is a myosatellite cell?
Stem cell that helps repair damaged muscle tissue.
What is the sarcolemma?
Plasma membrane of a muscle fiber that surrounds the sarcoplasm.
What is sarcoplasm?
Cytoplasm of a muscle fiber.
What is a myofibril?
Long contractile fibers within a muscle fiber responsible for muscle contraction.
What are transverse tubules (T tubules)?
Narrow tubes that are continuous with the sarcolemma and extend deep into the sarcoplasm, transmitting action potentials from sarcolemma into cell interior.
What is the sarcoplasmic reticulum (SR)?
A tubular network surrounding each myofibril, specialized for storage and release of calcium ions.
What is a triad?
Formed by two terminal cisternae plus a T tubule.
What are thin filaments primarily composed of?
Actin (protein).
What are thick filaments primarily composed of?
Myosin (protein).
What are voluntary muscles?
Muscles that contract only when stimulated by the central nervous system.