Muscular system - general knowledge Flashcards
What are the three types of muscle?
- skeletal striated muscle
- cardiac striated muscle
- smooth muscle
Describe skeletal striated muscle
- voluntary and somatic (controlled by SNS)
- makes up gross skeletal muscle
- function to move and stabilize bones and other structures
Describe cardiac striated muscle
- involuntary and visceral
- forms most of the walls of the heart and adjacent great vessels
- functions to pump blood
Describe smooth muscle
- involuntary and visceral
- forms part of the walls of vessels and hollow organs
- moves substances through using coordinated sequential contractions
What is peristalsis?
coordinated, sequential contractions that move substances through vessels and organs
What are the different parts of skeletal muscle?
- heads or bellies: fleshy, reddish, contractile portion
- tendons: white, non-contractile portions
Composition of tendons
mainly of organized collagen
What is aponeurosis?
flat sheet formed by some tendons that anchor muscle to skeleton, deep fascia and/or aponeurosis of another muscle
When referring to the length of a muscle, what is included
both belly/head and tendon
How are muscles classified?
by muscle fiber arrangement and shape
What are the 6 classifications of muscles?
- flat
- fusiform
- pennate
- quadrate
- circular
- multi-headed (multi-bellied)
Describe flat muscles
parallel fibers, often with aponeurosis
Describe fusiform muscle
spindle-shaped with a round, thick belly and tapered ends
Describe pennate muscles
- featherlike arrangement of fibers
- can be unipennate, bipennate or multipennate
Deltoid is an example of what type of muscle?
multipennate
Extensor digitorium and palmar interossei are examples of what type of muscle?
unipennate
Rectus femoris and dorsal interossei are an example of what type of muscle?
bipennate
Describe quadrate muscles
have four equal sides.
Biceps brachii is an example of what type of muscle?
fusiform
External oblique and sartorius are examples of what type of muscle?
flat
Rectus abdominis between its tendinous inscriptions is an example of what type of muscle?
quadrate
Orbicularis oculi is an example of what type of muscle?
circular
Describe circular muscles
surround body opening or orifice and constrict when contracted