(Part 3) Class 7 - Muscle Tissue (Neuro and Chemical) Flashcards
What is ATP and what does it do?
ATP (Adrenosphene Triphosphate) is the body’s most important energy transfer molecule. It is key in muscle contraction.
The neurochemical _____ also known as ____ functions as a chemical messenger in the excitation phase of muscle action.
ACh, (ascetylcholine)
A myofibril in a muscle is a bundle of ____________.
Myofilaments
There are 3 kinds of myofilaments, elastic filaments, ________ and ___________.
Thick Filaments (Myosin) and Thin filaments (Actin).
Myosin and actin are called _____ ______ because they _____ the muscle fibers.
contractile protiens, shorten
________ is the calcium _______ protein in muscle contraction.
Actin, binding
________ ________ are made of several hundred _____ molecules that have golf club shaped heads in the bundle.
Thick myofilaments, Myosin
_____ ______ are made of two intertwining strands of ______ with calcium binding molecules attached.
Thin myofilaments, Actin
The contractile proteins ____ and _______ interact with the ______ proteins (tropomyosin and troponin) to contract a muscle fiber which is activated by the release of ______ into the ______ and its binding to troponin.
Actin, Myosin, regulatory, Calcium, sarcoplasm
In sliding filament theory a _________ or the segment of myofibril between one _______ and the next shortens and pulls pull the ______ closer together due to contractile proteins myosin and actin’s actions.
Sarcomere, z-disk, z-disks,
A ______ _______ consists of one nerve fiber and the ______ _______ it innervates.
motor unit, muscle fibers
True or False: Actin and Myosin shorten during contraction.
False. They cause the individual sarcomeres to shorten and z disks to come closer together.
Skeletal muscle never contracts unless _____ by a _________.
stimulated , nerve
When muscle fibers contract in a motor unit, they contract ______ ______.
in unison.
A _______ is a gap where chemical transfer occurs and a nerve fiber meets its _____ ____ in the neuromuscular junction.
synapse, target cell
_______ cells envelope a neuromuscular junction and isolate them from surrounding tissue fluid.
Schwann
Three ways a signal stops in the neuromuscular cycle are ________, ________ and ________.
diffusion, reuptake and degradation ( with AChe)
In the excitation phase _______ stimulates the release of _______ to prepare the muscle fiber for the next phase toward contraction.
ACh (ascetalcholine),calcium
In contraction the ___ head must have an ____ molecule bound to it to initiate the process.
myosin, ATP
_______ ________ is a disease caused by lack of ACh receptors.
Myasthenia gravis.
A strain is a tear in __ or _____. A sprain is a tear in _________.
Muscle, tendon, ligament.
Cardiac muscle is ____ like skeletal muscle and it is repaired by __.
striated, fibrosis
