Muscles

    Muscles
    Which molecule in a muscle cell has a cross-bridge that attaches to a binding site to effect the shortening of the cell?
    Myosin (the thick filament) has a cross-bridge that attaches to a binding site on actin (the thin filament) when it is exposed.
    Author: rikazzz Comment
    Muscles
    Which list is in the correct order of DECREASING size?
    A myofibril consists of sarcomeres joined end to end; a myofibril contains many myofilaments; a myofibril is larger than a molecule of myosin.
    Author: rikazzz Comment
    Muscles
    By what name is the plasma membrane of a muscle cell known?
    “Sarco-” refers to flesh (muscle); “lemma-” refers to sheath (membrane) around the cell.
    Author: rikazzz Comment
    Muscles
    What is the gluteus maximus named for? Its:
    The gluteus maximus is larger than either the gluteus medius or gluteus minimus.
    Author: rikazzz Comment
    Muscles
    Which of the following describes skeletal muscle?
    Skeletal muscle is striated and is not branched (cardiac muscle cells are branched).
    Author: rikazzz Comment
    Muscles
    One muscle below is NOT named after its shape. Which one?
    The masseter is named after its action which allows mastication (chewing) of food.
    Author: rikazzz Comment
    Muscles
    A skeletal muscle fibre (cell) consists of many sections (units) which contract. What is the name given to one of the units that contract?
    A muscle fibre consists of many sections (sarcomeres) connected end to end that shorten (contract) as the thick and thin filaments slide past each other.
    Author: rikazzz Comment
    Muscles
    What is the role of acetylcholine in muscle cell contraction?
    ACh crosses the synaptic cleft to transmit a neural impulse to the muscle sarcolemma.
    Author: rikazzz Comment
    Muscles
    What is a “sarcomere”?
    A myofilament is a long line of sarcomeres joined end to end. So one section of a myofilament is a sarcomere.
    Author: rikazzz Comment
    Muscles
    Which one of the following is NOT a characteristic of skeletal muscle?
    Skeletal muscle is voluntary and so is innervated by the somatic nervous system, not the autonomic system.
    Author: rikazzz Comment