CH10 Flashcards
(48 cards)
Characteristics of skeletal muscle
- Location: Skeletal, sphincter, urethra, anus
- Function: Moves bones, produces heat
- Appearance: multinucleated; striated
- Voluntary
Characteristics of cardiac muscle
- Location: Heart
- Function: pump blood
- Appearance: striated; one nucleus; intercalated disc (specialized junctions to connect cardiac muscle)
- Involuntary
Characteristics of smooth muscle
visceral
- Location: walls of hollow internal organs; vessels, airways, stomach, bladder, uterus
- Function: moves materials through organs
- Appearance: smooth; one nucleus
- Involuntary
Properties of muscular tissue
- Electrically excitable: produces electrical signals (action potentials) when stimulated
- Contractility: ability of muscle to shorten/lengthen and produce force in response to a stimulus
- Extensibility: the ability of a muscle to be stretched or extended without damage
- Elasticity: ability of muscles to return to their original length after being stretched or contracted
Function of muscular tissue
- Produce body movement
- Stabilize body positions
- Storing and moving body substances within the body
- Generating heat
Fascia
most superficial connective tissue of skeletal muscles and anchors muscles and other organs of the body
Fascicles
bundles of muscle fibers within skeletal muscles, covered by perimysium
Muscle fibers
the individual, elongated cells that make up muscle tissue, responsible for contraction and movement, gives striated appearance, covered by endomysium
Epimysium
- outer layer, covers skeletal muscle, overlies sarcolemma (muscle cell membrane)
- allows the muscle to contract and move powerfully while maintaining its structural integrity, and separates tissues
Perimysium
covers each fascicle and separates them
Endomysium
surrounds each fiber, contains extracellular fluid and nutrients to support muscle fiber
What tissues fuse muscle and tendon together?
Epimysium, perimysium, endomysium
Tendons
rope-like connective tissue anchors muscle to bone
Aponeurosis
- sheet-like (flat) connective tissues. Attached muscle to bone or muscle to muscle
- EX: latissiumus dorsi and linea alba
Cell parts (of muscle)
Sarcolemma
plasma membrane of muscle fibers
Cell parts (of muscle)
T tubules
extensions of the sarcolemma that go deeper into the muscle fiber and allows action potentials to reach further into the interior of the cell
transverse tubules
Cell parts (of muscle)
Action potential
a brief electrical signal that allows nerve cells (neurons) and muscle cells to transmit information
Cell parts (of muscle)
Sarcoplasm
cytoplasm
Cell parts (of muscle)
Sarcoplasmic reticulum
smooth endoplasmic reticulum, where Calcium is released
Cell parts (of muscle)
Myofibrils
specialized contractile organelles found within muscle fibers, made up of 3 proteins - contractile, regulatory and structural
Contractile proteins
generate force during muscle contraction (myosin and actin)
Regulatory proteins
determine when muscle contracts and relaxes (troponin and tropomyosin)
Structural proteins
keeps thick and thin filaments in alignment, links myofibrils to sarcolemma (titin, nebulin, alpha-actin, myomesin, dystropohn)
Sarcomere
- Functional unit of a skeletal muscle fiber; region from one Z-line to the next Z-line
- Linked together (end to end) creating myofibrils.
- Composed of actin (thin) filaments and the myosin (thick) filaments.
- Sarcomeres are divided into bands and zones depending on the area and contain thick filaments, thin filaments, or both.