Chapter 10: Muscular Tissue Flashcards
What are the special properties we find in muscular tissue
- Excitability
- Contractibility
- Extensibility
- Elasticity
What does it mean for a muscle to be excited
To go from polarized to depolarized
What does contractility mean
Tightening or shortening a muscle
What is Extensibility
Allows muscle cells to be stretched
What is Elasticity
Ability to recoil or bounce back a muscle to original length after being stretched
Describe Smooth muscles
- Do not contain striations ( NON-striated)
- Spindle shaped and unnucleated (one nucleus)
- Found in the wall of the blood vessels, stomach, intestine, in the wall of hollow organs!!!
- Involuntary control (Autonomic control) we can’t control it
Describe Cardia muscles
- Striated and Branched
- Unnucleated
- Intercalated disc
- Desmosome= hold the muscle together
- Gap junctions= Allows for easier communication between muscles and form a wave like pattern
- Involuntary (Think of the heart)
Describe Skeletal Msucle
- Voluntary movement (Somatic)
- Multinucleated, tubular, and striated
- Very long
- Attached to skeleton
Important to remember
Cell division of cardiac and skeletal muscle DOES NOT HAPPEN after birth only BEFORE
Important to remember 2
Smooth muscle can undergo cell division AFTER birth
Functions of Muscular Tissue
- Storage of substances, because we find muscles making up the wall of organs
- Moving things around - Voluntary body movement
- Maintenance of body posture
- Muscle contraction produces heat
Two types of filaments found in muscles
Actin and Myosin
This filament is Thin
Actin
This filament is Thick
Myosin
How does contraction happen
Myosin pulls on Actin and shortens the filaments, contracting the muscle
What are pacemakers
Stimulate contraction for the cardiac muscle
Skeletal muscle
- Extremely long
- Multinucleated
- Striated muscle
- Come from fusion of several myoblast
myoblast= cells born to build muscle
What are Sarcomere
Flesh units
- They arrangement of sarcomere in line is called MYOFIBRIL
- Between sarcomere you have a Z line
What light can pass through we call it
Isotropic also called I band (light band)
When light cannot pass through we call it
Anisotropic also called A band (Dark band)
Breakdown
I Band= Contain thick filaments
A Band= Contains both thick and thin filaments
H band= Contains Thick filaments
M line= Middle of sarcomere that anchor the myosin together
Z line= ENDS of a sarcomere that anchors the thin filaments
Review notes once mastered this
Review notes
