Muscle Terminology
What is the wrapping that surrounds the entire muscle called?
Epimysium
What are the layers of muscle tissue called? Start with Muscle, end with myofilament.
(muscle, Fascicle, Fibers, Myofibrils, myofilament)
What is the effect of tetanus on muscle contraction?
Tetanus stimulates muscle resulting in excessive ACh in the synapse. Muscle will contract without the ability to relax.
What is the origin of a muscle?
The location of muscle attachment (usually a bone) that does not move when the muscle pulls.
The word that characterizes a muscle with a circular fiber direction.
orbicularis
Hamstring
Why would botulism toxin (Botox) work to reduce wrinkles?
Botox prevents the release of ACh into the synapse. Therefore the muscle cannot be stimulated to contract. The muscle will be relaxed and the skin will not wrinkle.
The insertion is the place where the muscle ______.
Attaches to a moving bone or location.
sternum, clavicle and mastoid of the skull
Which muscles extend the neck and which flex?
Trapezius extends, sternocleidomastoid flexes.
What are the three layers of wrapping of the muscles? (Connective Tissue)
Epimysium, Perimysium and Endomysium.
Explain why myasthenia gravis has the symptoms it does.
The fatigue in muscles is due to the destruction of ACh receptors on the muscle cell membrane. This prevents the ACh from connecting with the receptors to signal the muscle to contract leading to tiredness and over relaxation of muscles.
Where should a greater than 5cc intramuscular injection be administered?
The gluteus medias
What are the muscles usually observed in a genuine smile?
Zygomaticus, frontalis and o. oculi
What is the role of Calcium, troponin and tropomyosin?
Calcium binds to troponin which shifts the tropomyosin away from the crossbridge binding sites so that they can form allowing actin to slide towards myosin.
It takes 12 hours for a body to stiffen after death in a head to toe direction. It then takes another 12 hours for the body to relax also in the head to toe direction.
What type of fibers would be found in a marathon runner's muscles? Which type of cellular respiration would take place there?
Give the literal meaning of the terms, prime mover and antagonist.
prime mover: muscle that does the action in a movement.
antagonist: Muscle that does the opposite action of a movement.
The flexor carpi ulnaris.
Describe the role of acetylcholine in muscle contraction.
Acetylcholine is found in vesicles that are found in the axon terminal. Calcium triggers the vesicles to release ACh into the synapse and then the neurotransmitter binds to the receptors on the muscle to continue the process of muscle contraction.
If a patient entered the ER with muscle weakness, how could the clinician figure out whether it was atrophy or dystrophy?
If the electromyography (EMG) results showed that the muscle did contract with the signal it would be atrophy. If not, it would be dystrophy because the muscle is defective even with an electrical signal.