Chapter 20 - Muscular System and Pathologies Flashcards
(128 cards)
What is the study of muscular system?
myology
What are the important functions of the muscular system?
movement, posture maintenance, and heat production
What is posture?
body positions maintained by muscle contractions
What is a muscle tone or tonus?
continuous and partial contraction of skeletal muscles
What is it called when the skeletal muscles are the most metabolically in the body and produce a significant amount of heat?
thermogenesis
What is another term for muscle cells?
muscle fibers
What is sarcolemma?
cell membrane surrounding muscle fibers
What are the folds in the sarcolemma?
motor end plates
What is the intracellular fluid within the muscle fibers?
sarcoplasm
What are myofibrils?
thousands of slender strands in muscle fibers
What are the basic units of muscle contraction?
sarcomeres
What borders each sarcomere?
Z lines (or Z discs)
What type of filaments are made of three proteins: actin, tropomyosin, troponin?
thin filaments
What type of filaments are made up of entirely of myosin?
thick filaments
What is also called a striated muscle?
skeletal muscle
What are the combination of thin filaments and Z lines?
I bands
What is the center of a sarcomere containing only thick filaments and devoid of thin filaments?
H zone
Which band runs the entire length of thick filaments?
A bands
What surrounds the myofibril within muscle fibers?
Sarcoplasmic reticulum
What are the indentations on the sarcoplasmic reticulum that travel deep into the muscle fibers?
transverse tubules (T tubules)
What are the individual muscle fibers that is surrounded by a layer of connective tissue?
endomysium
What are fasciculi?
bundles of muscle fibers
What is the layer of connective tissue that surrounds each fascicle?
perimysium
What is an epimysium?
groups of fasciculi surrounded by connective tissue