Lab 20 - Skeletal Muscle Structure and Function
Layer of connective tissue that surrounds an individual muscle fiber.
Endomysium
Layer of connective tissue that surrounds a skeletal muscle.
Epimysium
(T/F) The role of a particular muscle is always the same.
False
Connective tissue located between adjacent muscles.
Fascia
A small bundle of muscle fibers.
Fascicle
Protein found within thick filament.
Myosin
Layer of connective tissue that separates a muscle into small bundles called fascicles.
Perimysium
Plasma membrane of a muscle fiber.
Sarcolemma
Unit of alternating light and dark striations between Z lines.
Sarcomere
Cytoplasm of a muscle fiber.
Sarcoplasm
Cellular organelle in muscle fiber corresponding to the endoplasmic reticulum.
Sarcoplasmic Reticulum
Cordlike part that attaches a muscle to a bone.
Tendon
Membranous channel extending inward from muscle fiber membrane.
Transverse (T) Tubule
(T/F) A synergist muscle contraction assists the prime mover.
True
(T/F) The plasma membrane of a muscle fiber (cell) is called the sarcolemma.
True
When the biceps brachii acts as the prime mover, the ________ muscle assists as a synergist.
brachialis
The outermost layer of connective tissue of a muscle is the A) fascicle B) endomysium C) epimysium D) perimysium
epimysium
The ________ of a muscle is usually attached to a moveable location.
insertion
The neuron and the collection of muscle fibers it innervates is called the A) neural impulse B) muscle fiber C) motor neuron D) motor unit
motor unit
The thick myofibril filament of a sarcomere is composed of which protein? A) myosin B) actin C) titin D) sarcolemma
myosin
The ________ of a muscle is usually attached to a fixed location.
origin
A muscle responsible for most of a movement is called a ___________.
prime mover
The muscle primarily responsible for a movement is the A) synergist B) prime mover (agonist) C) antagonist D) origin
prime mover (agonist)
Antagonists are muscles that resist the actions of _________ and cause movement in the opposite direction.
prime movers
The functional contractile unit of a muscle fiber (cell) is a A) sarcoplasm B) sarcolemma C) sarcomere D) sarcoplasmic reticulum
sarcomere
Assisting muscles are called _________.
synergists
When the forearm is extended at the elbow joint, the ________ muscle acts as the prime mover.
triceps brachii