MUSCLE TISSUE MIDTERMS Flashcards
limited to Heart (Myocardium) and Large Blood Vessels
attached to heart
CARDIAC
Present in walls and parenchyma of most visceral organs,
walls of blood vessels and skin
SMOOTH
Comprised all named voluntary muscles in the body (ex.
Gastrocnemius, Latissimus Dorsi)
* Most originate and/or insert in bone
SKELETAL
- Connective tissue which envelops muscles
- A dense irregular connective tissue that surrounds the
entire skeletal muscle
Epimysium
- Connective tissue which envelops muscle
bundles/fascicles - Less dense and thinner irregular connective tissue layer
Perimysium
A thin layer of particular connective tissue fibers which
invests now into individual muscle fibers that will separate
each muscle fiber
Endomysium
Equivalent to your skeletal muscle fiber
Muscle cell
- Long and cylindrical
- Multi-nucleated (nucleus is located peripherally)
- Each pf this muscle fiber of subunit is called your
myofibrils
Skeletal muscle fiber
o Extends the entire length of your fiber
o Composed of smaller myofilaments which
formed the contractile thin protein actin and a
thick protein myosin (thick and thin filaments)
Myofibrils
Light Band
(I-Band)
Dark Band
(A-Band)
o Zwischenscheiben Line; Z-band; Z-disc
o dark line which bisects I-Band
Z-Line
o Z-line to Z-line
o Repeating units which make up Myofibrils
Sarcomere
o Henle’s Band; Heller Band; Hell Band; Henson’s
Band
o lighter zone in center of A-Band
H-Band
o Mittelscheibe Line
o thin, dark band which bisects the H-Band
M-Line
- contract rapidly but briefly
- fatigues fast
- low Myoglobin content
- fewer Mitochondria; large in diameter than red
- example: Extraocular Muscles
WHITE (FAST TWICTH) MUSCLE
- unique in cardiac muscles
- cross chain of cardiac cells at irregular interval
- represent junctional complexes of muscle cells
- Anchors Myofibrils
- Allows for instantaneous spread of contractile stimulus
INTERCALATED DISCS
- contract at slower rate but capable of continuous
contraction - do not fatigue easily
- richer blood supply than white
RED (SLOW TWICTH) MUSCLE
Appears as an elongated individual fiber with a fusiform
shape of slender bundles called your
fascicle
muscle cells (basic unit of your muscle)
Muscle Fiber
cell membrane of muscle cells
Sarcolemma
sER
Sarcoplasmic Reticulum
Sarcosomes
– mitochondria
Sarcoplasm
cytoplasm
Muscle is classified into three types:
skeletal, cardiac, and
smooth muscle.
The cytoplasm of muscle cells is called _____, and
the surrounding cell membrane or plasmalemma is called
________.
sarcoplasm and sarcolemma
All muscle tissues consist of elongated cells called
fibers
the term ______ is used when in contrast of the connective tissue fiber.
fiber
every muscle fiber is surrounded by a basal lamina called _____
Endomysium
its plasma membrane is called _____
Sarcolemma
within the sarcoplasm are the cytoplasmic contractile elements _____
myofilaments
a muscle that has the ability to conduct an action potential
conductivity
when stimulated the muscle will react
irritability
A muscle can shorten or produce tension between its ends
contractility
a muscle can return into resting properties after contraction
relaxation
a muscle can be stretched by a force outside of the muscle itself
distensibility
the muscle will resist elongation and will return to its original position after passive or active elongation
elasticity
