Muscular System ANATOMY Flashcards
The Muscular System
Integrated system of the body that is vital for controlling voluntary and involuntary movements.
All Muscles Functions
- Excitable- React to stimuli
- Contract- Cells shorten
- Extensibility- Cells stretch
- Elastic- Recoil/ Bounce back
Skeletal Muscle
- Attached to bone & involved in bone movement
- Work together in groups
- Striated Muscle
- VOLUNTARY MUSCLE (controlled consciously)
Cardiac Muscle
- Only found in Heart walls
- Striated Muscle
- INVOLUNTARY MUSCLE (controlled subconsciously)
Smooth Muscle
- Found in walls of HALLOW organs
- Weakest muscle tissue
- Spindled Shape (NOT STRIATED)
- INVOLUNTARY MUSCLE (controlled subconsciously)
How many named muscles in body?
700
make up approx HALF a person’s body weight
Muscle Tendons
Tough bands of connective tissue that have STRONG collagen fibers.
Collagen fibers firmly attach muscle to bone
Muscle Belly
Middle of muscle
Contracts when muscle moves
Perimysium
-Thin layer of connective tissue found in skeletal muscle
- Separates muscle into FASCICLES
Muscle Fascicle
Consists of bundles of muscle fibers (MYOCYTES)
Myocyte
SKELETAL MUSCLE FIBER!!!!
- Long cylinder cell with multiple nuclei
Sarcolemma
Cell membrane of muscle fibers (myocyte)
Transverse Tubules (T-Tubules)
Tubes located in middle of skeletal and cardiac Muscle Fibers (myocytes & cardiomyocytes)
Allows electrical pulses and CALCIUM to move deeper into the cell
Myofibril
Made up of 1000s of sarcomeres
- Contain THIN Actin filaments & THICK Myosin Filaments
Sarcomere
Contracting unit of muscle
Sacroplasm
Cytoplasm of Muscle Fiber
Contains smooth endoplasmic reticulum called SARCOPLASMIC RETICULUM
Epimysium
Dense connective tissue that surrounds the entire skeletal muscle
Cardiomyocyte
Cardiac Muscle cell contains one Nucleus
Endomysium
Smaller connective tissue that surrounds the individual myocytes, cardiomyocytes & smooth Muscle cells
Intercalated Disc
-Prevents cardiomyocytes from pulling apart
-Contains GAP JUNCTIONS to allow ions to flow from one cardiomyocyte to the other
Smooth Muscle Found in
- Small/ Large intestine
- Stomach
- Tracks of Reproductive System
- Blood vessels
- Skin
Striated Muscle
Muscle tissue where contraction fibers are aligned in parallel bundles
Looks striped
Fusiform Muscle
Spindle shaped muscle
Wide in middle tapered at both ends
Origin
Tendons attached to bone that doesn’t move when contracting
Insertion
Tendons attached to bone that move when contracting
