Bio107-ch9&10pt1&2 Flashcards
Functions of muscle (3)
- Motion/ movement
- Maintain posture
- Heat production
Characteristics of muscle (4)
- Excitability- responds to stimuli
- Contractibility- able to shorten
- Extensibility- stretches when pulled
- Elasticity- returns to original shape after movement
Muscle tissue types (3)
- Skeletal muscle tissue
- Cardiac muscle tissue
- Smooth muscle tissue
Skeletal muscle tissue (4)
- Biceps triceps
- Voluntary
- Striated
- Multinucleated
Cardiac muscle tissue (4)
- Heart
- Involuntary
- Striated- intercalated discs
- Multinucleated
Smooth muscle tissue (4)
- Around organs, arrector pilli
- Involuntary
- NO STRIATIONS
- ONE nucleus
Agonist
Does work
Antagonist
Does not do work
Synergistic muscles
Muscles that have the same action at a joint
Prime mover- agonist
Muscle with the greatest force of contraction or mechanical advantage
Synergists
Non Prime movers
Prime movers____ to cause desired action
Contract
Antagonists ____ and yield to _____
Stretches
Prime mover
Synergists ____ to stabilize nearby joints
Contract
Fixators ____ the origin of the prime mover
Stabilize
Resistance
Weight of a body part or object
Effort
Work done by muscle contraction
Skeletal muscle myofibril image:
1 sacromere =
From z disc to z disc
Actin
Thin filament
H zone
Down the middle, in between both z discs
Collapses during activity
A band
Area between both I bands
One end of myosin to the other, contains both actin and myosin
Myosin
Thick filament
M line
The middle
I band
One sacromere to the end of another
Contains actin only
Smaller units of skeletal muscle fibers are
Myofibrils
Thick filament has ____ that move ____
Heads
Move up and down back and forth
Actin contains (2)
Tropomysin and troponin
Sarcolemma stores
Calcium
Sarcolemma and T tubules surround
The myofibril
Sarcoplasmic reticulum
- Mesh-like
- Stores Ca for muscle contraction
- Paired terminal cisternae form cross channels
- Elongate T tubules allow Ca to flow or be stored
Excitation-contraction coupling, also called
Sliding filament theory