Chapter 8 Flashcards
Fascia
Dense connective tissue that separates an individual skeletal muscle from adjacent muscles and holds its position
Epimysium
Layer of convective tissue that closely surrounds each skeletal muscle
Perimysium
Extends inward from the epimysium and separates muscle tissue into small sections called fascicles
Fascicles
Bundles of skeletal muscle fibers
Endomysium
Sheath of connective tissue surrounding each skeletal muscle fiber
Aponeurosis
Sheet of convective tissue that attaches muscles to bone, skin, or to the coverings of adjacent muscles
Myofibril
Contractile fiber in striated muscle cells
Myosin
Thick filaments
Actin
Thin filaments
Sarcomeres
Structural unit of a myofibril and the functional unit of muscle contraction
L bands
Light bands composed of thin filaments directly attached to z lines
A bands
Dark bands that extend the length of the thick filaments
H zone
Central regions of a bands that consist only of thick filaments and are located between two regions where the thick and thin filaments overlap
M line
Consists of proteins that help hold the filaments in place
Sarcoplasmic reticulum
Membraneous network of channels and tubules within a muscle fiber corresponding to the endoplasmic reticulum of other cells
Transverse tubules
Any of several membranous channels that extend deep into the cell from a muscle fiber membrane
Cisternae
Enlarged portion of the sarcoplasmic reticulum near the actin and myosin filaments of a striated muscle fiber
Motor neurons
Neurons that control effectors
Synapse
The functional connection between a neuron and another cell
Neurotransmitters
Chemical that an axon secretes at a synapse that simulates or inhibits an effector or other neuron
Neuromuscular junction
Synapse between a motor neuron and a skeletal muscle fiber
Motor end plate
Specialized part of a muscle fiber membrane at a neuromuscular junction
Synaptic cleft
A narrow extracellular space between two cells at a synapse
