Exam 3: Chapter 20: Muscle Flashcards
What is muscle made up of?
Contractile cells
What two muscle components combine to allow movement?
Molecular motor myosin and energy from ATP
What contractile proteins generate force?
Actin and myosin
Where is striated muscle found?
Skeletal and cardiac muscle
The striated muscles found in skeletal and cardiac muscles have what?
Sarcomeres
What do skeletal muscles consist of?
Bundles of longitudinally arranged muscle fibers (cells)
What are 3 main characteristics of smooth muscle?
- Not striated
- Uses actin and myosin for contractions
- Surrounds organs, intestine, and blood vessels
Every muscle fiber contains what?
Myofibrils
What does each myofibril have?
Cross- striations, which are sarcomeres
What kind of muscle fibers make up vertebrate skeletal muscle cells
Long muscle fibers
What are the 5 main characteristics of vertebrate skeletal muscle regarding its structure and function?
- Made up of long muscle fibers
- Connective tissue forms tendons that attach to the muscles and bones
- Transmit force
- Have many nuclei
- Surrounded by a membrane called the sarcolemma.
What is the name of the membrane that surrounds vertebrate skeletal muscles?
Sarcolemma
What forms the tendons that attach to the skeletal muscles and bones
Connective tissues
What does each myofibril have in terms of bands?
Regularly repeating transverse bands
What are the names of the major bands in the myofibrils/ muscle fibers of the skeletal muscles?
Dark A and light I
What is the name of the functional unit of striated muscles?
The sarcomere
What is the Z line?
The line in the middle of each I band
The line in the middle of each I band is the …..
Z line
What is between the Z lines
The sarcomere
The sarcomere is between what lines?
Z lines
What contributes to the striated appearance of skeletal muscle?
The major bands (the dark A and the light I) and the lines/discs in sarcomere
Myofilaments are made up of….
Thick and thin parts
How many myosin proteins make up thick filaments?
200-400
What are thin filaments made up of?
Actin