Muscle part A Flashcards
long, multinucleated cells with many mitochondria
• Striated tissue under somatic (voluntary) control
• Located with skeletal bone
Skeletal
1 nucleus with gap junctions and desmosomes
(intercalated disks)
• Striated tissue under autonomic (involuntary) control
• Located in heart
Cardiac
short cells with 1 nucleus
• Non-striated tissue under autonomic (involuntary) control
• Located in digestive system, urinary bladder, blood vessels,
uterus
Smooth
MUSCLE FUNCTIONS
- Produce movement of body and fluids
- Maintain posture
- Stabilize joints
- Generate heat from contractions (mostly
skeletal)
____?(fiber) surrounded by connective tissue =
Cell, Endomysium
____?bundles of muscle fibers held together by collagen sheath =
Fascicles, Perimysium
____?bundles of fascicles held together by dense regular connective tissue
Entire Muscle, Epimysium
continues to form tendons that are the muscle origin and insertion
Epimysium
cord made of dense regular connective tissue that attaches muscle to periosteum of bone.
Tendon
Every skeletal muscle fiber has:
• Motor nerve ending = stimulates fiber
• 1 artery = supply oxygen and nutrients,
• 1 or more veins = carry wastes (CO2, H2O and lactic
acid) away
cell membrane has receptors for
neurotransmitters on surface is called?
Sarcolemma
cytoplasm containing glycogen
and myoglobin is called?
Sarcoplasm
What stores glucose?
Glycogen
oxygen storing pigment
Myoglobin
The continuation of
the sarcolemma to carry impulses into the
interior of the muscle cell is called?
Transverse tubule (T tubule
What specialized ER for
calcium storage and release?
Sarcoplasmic reticulum
bundles of overlapping contractile filaments
that extend the length of the muscle: Actin
and Myosin
give skeletal muscle striated appearance
Myofibrils
repeating functional unit; area of a myofibril between two Z discs is called?
Sarcomere
contain projections (myosin head) which fit into actin and make up thick filaments
Myosin
contains myosin binding site where myosin head
attaches and Make up thin filaments
Actin
myosin heads attach to actin is call?
Crossbridge formation
ADP released and crossbridges rotate
• generate force as they rotate toward center of sarcomere -> filaments sliding over each other
Power stroke
ATP binds to binding site on myosin is call?
Detachment of myosin heads
DEFINE MUSCLE FATIGUE
Inability of muscle to maintain contractions with
prolonged activity
additional oxygen taken into body after
exercise used to is?
Oxygen debt
Convert lactic acid back to glycogen in liver and replace CP and ATP in muscle
Oxygen debt
3–4 hours after death, muscles begin to stiffen
Rigor Mortis (Clinical – Homeostatic Imbalance 9.2)
Peak rigidity occurs about 12 hours postmortem
Rigor mortis (Clinical – Homeostatic Imbalance 9.2)
Intracellular calcium levels increase because ATP is no longer
being synthesized, so calcium cannot be pumped back into
SR
Rigor Mortis
Results in cross bridge formation
Rigor Mortis
ATP is also needed for cross bridge detachment
Rigor mortis
