Muscular System Packet 1- Test 7 Flashcards
How many muscles are in the muscular system?
Over 600
T/F
About 60% of the human body weight comes from the muscles
False
About 40%
What does the muscular system do?
- Helps with movement
- Supports posture
- Produces heat and energy
- Protects internal organs (not really though)
- Helps move blood, food, and waste products through the body
- Opens and Closes body openings
What are the four common traits that all muscles have
- Excitability/ Irritability
- Contractability
- Extensibility
- Elasticity
What is muscle tone
The ability for muscles to be slightly contracted at all times, even when not in use
T/F
Tone allows a person to be in a state of readiness to act
True
What is Excitability/ Irritability
- The ability to respond to a stimulus, such as a nerve or hormone
- Muscles can be stimulated electrically, mechanically, or chemically
What is contractability
- The ability to shorten and produce movement when stimulated
What is extensibility
- The ability to be stretched and lengthen, (AKA: Flexibility)
What is elasticity
- The ability to return to its original shape after contracting or stretching
What are the three MAIN types of muscles
- Cardiac
- Visceral
- Skeletal
Where do skeletal bones attach
The bones by tendons
Are muscles in the skeletal system voluntary or involuntary contractions?
USUALLY voluntary
What does voluntary mean
You have to send a signal to your brain to move or do something
What does involuntary mean
You DON’T have to think about moving a muscle
T/F
The skeletal system helps produce body movement
True
Are the skeletal system muscles striated or non-striated
Striated
Is the muscles in the skeletal system multinucleated
Yes
What are the two bands in a striated muscle
Light and Dark
T/F
The light band on a striated muscle has a darker area called the H disk
False; It has a darker area called the Z disc
T/F
The dark band has a lighter area called the H zone or bare zone
True
Where are the visceral Muscles
In the walls of viscera, hollow organs, in the walls of blood vessels, and in the eyes
Why do visceral muscles contract
To produce movement in the organs it’s located in
Are visceral muscles multinucleated
No, they have only one nucleus
Where is the cardiac muscle located
The walls of the heart
Why does the cardiac muscle contract
To circulate blood
Does a cardiac muscle have striations
Yes
How do the cells look in a cardiac muscle
The cells are long and branching, and fit closely together at junctions
T/F
The cardiac muscle has a centrally located nucleus
True
Whole muscle structure of the belly
Fleshy body of muscle between slender point of attachments
What is Fascia (Type of facia)
Layers of tough connective tissue surrounding large skeletal muscles
What is Endomysium (Type of facia)
Surrounds individual muscle fibers
What is Perimysium (Type of facia)
Surrounds small bundles of fibers
What is Fascicles (Type of facia)
Bundles of muscle fibers
What is Epimysium (Type of facia)
Outer layer of fascia
What is a tendon (Type of facia)
A strong, cordlike fascia that extends toward and attaches to bone
What is Sarcolemma (Muscle Fiber Structure)
cell membrane of a muscle fiber
What is Sarcoplasm (Muscle Fiber Structure)
Muscle cell cytoplasm
What are Myofilaments
Contractile elements of each muscular fiber (actin and myosin)
What are Transverse Tubules (Muscle Fiber Structure)
Points of cell membrane
