The Musculoskeletal System - Muscles Flashcards
What is the difference between extensibility and elasticity?
Extensibility - ability to be stretched
Elasticity - ability to return to the original length after being stretched.
What are the 3 properties that allow muscles to create movement?
Extensibility
Elasticity
Contractibility
Describe the structure of skeletal muscle.
- muscles are held together in bundles
- sheath of connective tissue surrounds each bundle
- connective tissue allows adjacent bundles to slide easily over on another as they contract
Fill in the missing words:
Around the cell is a _____, ________ plasma membrane known as the ____________. It contains cytoplasm called the ___________.
a) thin
b) transparent
c) sarcolemma
d) sarcoplasma
What are the 2 types of myofilaments?
- thick myofilaments, composed of the protein myosin
- thin myofilaments, composed of the protein actin
Why is it that cardiac muscles appear striated?
The arrangement of thick and thin filaments within a myofibril gives a banded effect to the muscle.
Complete the following sentence:
Skeletal muscle is made up of bundles of _______ ______, each of which contains _______, which contain _________ of two types; ________ and ________
a) muscle fibres
b) myofibrils
c) myofilaments
d) actin
e) myosin
What is the name given to the model which explains how muscle contraction occurs?
The ‘Sliding Filament Theory’
Coordination of paired muscles provides body movement. Give an example and state which is the antagonist and agonist
- triceps and biceps
- when the biceps contract, the triceps relax. In this case, the biceps are the agonist and triceps are the antagonist.
What is the antagonist?
What is the agonist?
The antagonist
The agonist is the muscle that causes a desired action
What is the synergist?
Synergists are muscles that help the prime mover (agonist) and prevent unwanted movement so that the prime mover can function more efficiently.
Name one place in the body where smooth muscle can be found.
The iris
