Unit 4: Muscular System Pt. 1 Flashcards
Describe skeletal muscles:
Multi or mononucleate?
Striated or non-striated?
Unique characteristics?
Voluntary or involuntary?
Functions?
Locations in the body?
Multinucleated
Striated
Long and cylindrical
Voluntary
Movement, breathing, talking, etc.
Attached to bones
Describe cardiac muscles:
Multi or mononucleate?
Striated or non-striated?
Unique characteristics?
Voluntary or involuntary?
Functions?
Locations in the body?
Mononucleated
Short
Striated
Intercalated discs
Involuntary
Pumps blood
In the heart
Describe smooth muscles:
Multi or mononucleate?
Striated or non-striated?
Unique characteristics?
Voluntary or involuntary?
Functions?
Locations in the body?
Mononucleated
Short
Non-striated
Arranged in sheets
Involuntary
Move food/feces through GI tract, control airflow, erect hairs, etc.
GI tract, lungs, etc.
Define prime mover
Muscle doing the most work in movement
Define synergist
Muscles that assist with movement
Define antagonist
Muscle that gets stretched and resists
List the 3 functions of the muscular system
Movement
Thermoregulation
Communication
Define excitability
Responds to stimuli with electrical activity
Define conductivity
Excitation triggers the spread of excitation along muscle fibers
AKA action potential
Define contractility
Shortens when stimulated
Define extensibility
Able to stretch
Define elasticity
Bounces back after being stretched
What happens when a muscle shortens?
It converts chemical energy ATP to mechanical energy
What opens when excitation occurs and what is released?
Voltage-gated sodium channels open at synapse and release Acetocholine (ACh)
What happens after ACh is released?
Binds to ACh receptors, which allows sodium into the cell
As the charge becomes more positive due to the sodium, additional voltage-gated sodium channels open
