Muscles Flashcards
What are the three types of muscle?
Cardiac, Smooth, and Skeletal
How are muscles described when looked at under a microscope?
Striated, Spindle, and non-striated
What are Smooth Muscles
Small spindle shaped fibers.
no distinctive markings.
not attached to bone
don’t tire easily
involuntary and controlled by automated nervous system
remain contracted for periods of time
Where are smooth muscle located?
They are located in internal organs such as the stomach, intestines, uterus, bladder, and blood vessels
What are cardiac muscles?
Cardiac muscles are located in the heart
Striated and Branched
Involuntary
Cells are fused together by intercalated discs
What are Skeletal Muscle?
Muscles that connect to bone
Striped or Striated due to light and dark bands running perpendicular to the muscle
Voluntary muscle
Contract easily and fatigue quickly
What is a muscle fiber?
One muscle cell
What is the Sarcolemma and Sarcoplasm
The sarcolemma is the muscle cell membrane and sarcoplasm is the material inside the cell except for the nucleus.
What are the 4 characteristics of muscles?
Contractability
Excitability
Extensibility
Elasticity
What is contractability?
The ability to shorten or contract
What is Excitability and Action potential?
Response to stimuli aka irritability.
Action potential- the ability to respond to stimuli producing an electric signal.
What is Extensibility?
The ability to be stretched.
What is Elasticity?
The ability to come back to original length after being stretched.
Fast Twitch muscle fiber
Doesn’t use oxygen for energy anaerobic
Best for explosive movements
Fatigue quickly
Best suited for: short bursts of energy
Slow twitch muscle fiber
Efficient in using oxygen (aerobic)
Delayed muscle firing
Do NOT fatigue easily
Best suited for endurance sports
How many muscles are there?
Over 650
Skeletal Muscle Functions
Produce heat when they move
Majority attach to bone for leverage in order to pull
Exert force in order to move at joints
Muscles attache to tendons
What is the Origin, Insertion, and Belly of a muscle?
Origin- part of muscle that attaches to a fixed part of bone
Insertion- part of muscle attached to a moveable part (such as the radius)
Belly- the central body of the muscle
What are Prime Mover and Antagonist
Muscles come in pairs The prime mover moves in one direction (usually contracted) and the antagonist moves in the other direction (usually extended)
Muscles contract because of what 2 events?
Myoneural stimulation and Contraction of Muscle proteins
Isotonic contraction vs. isoetric contraction
Isotonic contraction is when the muscle contracts and shorten
Isometric Contraction is where the muscle tension increases but doesn’t shorten (trying to lift something heavy but it wont move)
Muscle Atrophy
Loss of muscle through disease or lack of use
Muscle Hypertrophy
An increase in Muscle Mass
Strains
Twisting or pulling of a muscle
Acute vs. Chronic Strain
Acute is from a tramautic blow or improper lifting techniques
Chronic is from overuse
