What is sarcolemma in cardiac muscle?
The sarcolemma is the plasma membrane of the muscle cell and is surrounded by basement membrane and endomysial connective tissue. The sarcolemma is an excitable membrane and shares many properties with the neuronal cell membrane.
Do cardiac muscles have sarcolemma?
Intercalated discs are part of the cardiac muscle sarcolemma and they contain gap junctions and desmosomes. Contractions of the heart (heartbeats) are controlled by specialized cardiac muscle cells called pacemaker cells that directly control heart rate.
Is sarcolemma part of a muscle fiber?
The sarcolemma is the cell membrane of the muscle fiber, and the endomysium is the connective tissue layer over the muscle fiber. Within muscle fibers, myofibrils are found running the length of the cell. Myofibrils can be described as units of a muscle cell made up of organized proteins consisting of sarcomeres.
What is sarcolemma and sarcolemma?
Anatomical terminology. The sarcolemma (sarco (from sarx) from Greek; flesh, and lemma from Greek; sheath) also called the myolemma, is the cell membrane of a muscle cell. It consists of a lipid bilayer and a thin outer coat of polysaccharide material (glycocalyx) that contacts the basement membrane.
What is Sarcoplasm and sarcolemma?
sarcoplasm: The cytoplasm of a myocyte. sarcolemma: The cell membrane of a myocyte. sarcomere: The functional contractile unit of the myofibril of a striated muscle.
What is the sarcolemma composed of?
It consists of a lipid bilayer typical of a plasma membrane and a thin outer coat of polysaccharide material, called glycocalyx, that contacts the basement membrane and allows the cell to anchor into the tissues that build and support muscle fibers.
What is sarcoplasm and sarcolemma?
What does the sarcolemma release?
The neurotransmitter acetylcholine diffuses across the synaptic cleft, causing the depolarization of the sarcolemma. The depolarization of the sarcolemma stimulates the sarcoplasmic reticulum to release Ca2+, which causes the muscle to contract.