Myology Flashcards
Myology Definition
Study of muscles
Skeletal Muscle Composed Of
Made up of muscle fibers. Each skeletal muscle is an organ.
Functions of Skeletal Muscle
Body Movement Maintenance of Posture Temperature Regulation Storage and Movement of Materials Support
Tendons
Dense Regular CT
Aponeuroses
Connect muscles to bone
Aponeuroses
Flattened, sheetlike tendons
Muscle fiber wrapped around what?
Endomysium
Fascicles
Groups of muscle fibers
Fasicle surronded by?
Perimysium
Muscle surronded by?
Epimysium
What surrounds the CT Wrappings?
Deep Fascia
Superficial Fascia Location
Superficial Fascia superficial to deep fascia
Sacrolemma
Muscle cell membrane, surrounds the muscle cell
Sacroplasm
Cytoplasm within the muscle cell
Sacroplasmic Reticulum
It has cell organelles like lysosomes, ribosomes, and endoplasmic reticulum
Sacroplasmic Reticulum Functions
Stores Calcium ions (Ca2+) and releases them when the muscle contracts
Transverse Tubules (T-Tubules) Function
Conducts nerve impulse quickly from sacrolemma through muscle fiber
Muscle fiber primarily composed of?
Myofibrils
Myofibrils
Run the length of muscle, as long as muscle fiber
Myofibril composed of?
Myofilaments
Myofilaments
Need to run length of muscle. Protein filaments
Thick Myofilaments name?
Myosin
Thick Myofilament
Each thick myofilament surrounded by six thin myofilaments
Thin Myofilaments name??
Actin
Light Bands Name
I Bands
I Band Components
Thin Myofilaments only
Thin doesn’t block light
Shortens when contracted
Dark Bands Name
A Bands
A Bands Components
Thick and Thin Myofilaments
Can block more light
Doesn’t shorten
Dark structure in the middle of an I Band?
Z Disc
Z Disc
Dark structure in the middle of an I Band
Thin myofilaments attach
Doesnt Shortens when contracted
H Zone
Lighter, Central Region in the Middle of A Band
Shortens when contracted
What kind of filaments are in H Zone
Thick Myofilaments
M Line
Dark Line in middle of H Zone
Doesnt Shortens when contracted
What kind of Filaments attach to M Line
Thick Myofilaments
Sacromere
Runs from Z Disc to Z Disc
Muscle will contract from one Z Dick to Another
Many Sacromeres along length of muscle fiber
Shortens when contracted
Sliding Filament Model of Contraction
Thick and thin myofilaments slide over one another
When muscles contract, they begin to overlap
Sacromeres shorten, H Zones Narrow, I Bands Narrow
Muscle Components from smallest subunits to the largest
Myofilament Myofibril Muscle Fiber Fascicle Muscle