Exam 3 deck 4 Flashcards
What muscle is primarily responsible for preventing foot drop?
Extensor digitorum longus
What is the main factor that determines the power of a muscle?
The total number of muscle cells available for contraction
What is a muscle that provides the major force for producing a specific movement called?
An agonist
Which of the following muscles is not a rotator cuff muscle ? A. Subscapularis B) teres minor C) supraspinatus D) levator scapulae
D- levator scapulae
Connective tissue covering a bundle of muscle fibers
Perimysium
Bundle of muscle fibers
Fascicle
Contractile unit of muscle
Sarcomere
A muscle cell
Myofilament
Thin areolar connective tissue surrounding each muscle fiber
Endomycium
Plasma membrane of the muscle fiber
Sarcolemma
A long organelle with a banded appearance found within muscle fibers
Myofibril
Actin or myosin containing structure
Myofilament
Cord of collagen fibers that attaches muscle to a bone
Tendon
Why is the connective tissue wrappings of skeletal muscle important?
It increases coordination, adds strength, and serves as a route for entry and exit of blood vessels/nerves to muscle
Why are there more indirect muscle attachments to bone than direct?
hey can get through prominences that would destroy other delicate tissues and can easily pass over joints
How does an aponeurosis differ from a tendon structurally?
Tendons attach muscle to bone and aponeurosis attaches muscle to muscle
How is aponeurosis functionally similar to a tendon?
They both function to connect muscle to something
The junction between a motor neurons axon and the muscle cell membrane is called a ____ junction.
Neuromascular
A motor neuron and all of the skeletal muscle fibers it stimulates is called a ______.
Motor unit
The actual gap between the axon terminal and the muscle fiber is called a ______.
Synaptic cleft
When the _______ reaches the ends of the axon the neurotransmitter is released and diffuses to muscle cell membrane to combine with receptors there.
Action potential
The combining of the neurotransmitter with the muscle membrane receptors causes a change in permeability of the membrane resulting in _______ of the membrane.
Depolarization
Within the axon terminal are many small vesicles containing a neurotransmitter substance called ________.
Acetylcholine
Botulinum toxin binds to receptors present at the axon terminal in order to enter the neuron. What vesicular transport process do you think is involved in the toxin entering the neuron?
Endocytosis
