Muscles Pt. 1 Flashcards
What are the characteristics of skeletal muscle?
- Striated.
- Voluntary.
- Moves bones.
What are skeletal muscles controlled by?
Somatic nervous system.
What are the characteristics of smooth muscle?
- Lacks striations.
- Involuntary.
Where are smooth muscles found?
In blood vessels, airways, and lining organs.
What are smooth muscles controlled by?
Autonomic nervous system.
What are the characteristics of cardiac muscle?
- Striated.
- Intercalated discs.
- Involuntary.
What is cardiac muscle controlled by?
Autonomic nervous system.
What are the functions of muscle?
- Produce body movement.
- Stabilize body position.
- Store and move substances w/in the body.
- Generating heat.
How does muscle move the body?
Through tendons that connect them to bones and ligaments that connect them to one another.
What are the muscles called that stabilize body position?
Postural muscles.
What muscles assist with storage and movement of substances in the body?
- Movement of gametes (smooth muscles in vas deferens and uterus).
- Uterus in blood vessel walls.
- Sphincters.
How do muscles generate heat?
They contract, causing shivering.
What are the 4 properties of muscle tissue?
- Contractility.
- Elasticity.
- Electrical Excitability.
- Extensibility.
What does contractility allow for?
The muscular tissue to contract forcefully when stm. by an action potential, allowing for tension generation.
What does electrical excitability allow for?
Responsiveness to action potentials.
What does elasticity allow for?
The muscle to return to its original length and shape after stretching.
What does extensibility allow for?
The muscle to stretch w/o being damaged.
What is the sarcolemma?
Muscle fiber plasma membrane.
What is the transverse tubule/T-tubule?
The sarcolemma extension that carries the action potential to the sarcoplasm.
What is the sarcoplasm?
The cytoplasm of muscle cells.
What is the sarcoplasmic reticulum?
The calcium storage, release, and reuptake unit.
What are terminal cisterns?
End portions of the sarcoplasmic reticulum that contact T-tubules.
What is a triad composed of?
T-tubules + 2 terminal cisterns on either side of the T-tubules.
What is actin?
The thin myofilaments.