Muscle Flashcards
- muscle cells
Muscle Fiber
- cell membrane of muscle cells
Sarcolemma
- sER
Sarcoplasmic Reticulum
- mitochondria
Sarcosomes
- cytoplasm
Sarcoplasm
- sequester (separate) calcium; specialized smooth ER
:
Sarcoplasmic reticulum
Muscle is classified into three types:
Skeletal muscle
Cardiac muscle
Smooth muscle
contractile filaments contain
actin and myosin
Contraction may be:
voluntary (skeletal muscles)
involuntary (cardiac and smooth muscles)
All muscle tissues consist of elongated cells called
fibers
The cytoplasm of muscle cells is called_________, and the surrounding cell membrane or plasmalemma is called___________.
sarcoplasm
sarcolemma
Comprised all named voluntary muscles in the body
Skeletal
Examples of skeletal muscle
Gastrocnemius
Latissimus Dorsi
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
skin
Smooth
contains bundles of very long, multinucleated cells with cross-striations.
Skeletal muscle
Their contraction is quick, forceful, and usually under voluntary control.
Skeletal muscle
also has cross-striations and is composed of elongated, often branched cells bound to one another at structures called intercalated discs which are unique to _______ muscle.
Cardiac muscle
Contraction is involuntary, vigorous, and rhythmic.
Cardiac muscle
consists of collections of fusiform cells which lack striations
Smooth muscle
Have slow, involuntary contractions
Smooth muscle
Skeletal Muscle:
Shape of fibers and number of nucleus
Cylindrical/ tubular
Multinucleated
Smooth Muscle:
Shape of fibers and number of nucleus
Spindle shaped
Uninucleated
Cardiac Muscle:
Shape of fibers and number of nucleus
Branched
Uni or Binucleated
Connective tissue which envelops muscles
Epimysium
external sheath of dense irregular connective tissue, surrounds the entire muscle
Epimysium
Connective tissue which envelops muscle bundles/fascicles
Perimysium
thin connective tissue layer that immediately surrounds each bundle of muscle fibers termed a fascicle
Perimysium
Surrounds muscle fibers
Endomysium
Surrounds the external lamina of individual muscle fibers.
Endomysium
Endomysium consists of
Basal Lamina + Free Reticular Fibers + Connective Tissues Elements
Where is the nucleus of skeletal muscle located?
Periphery
dark line which bisects I-Band
(middle of I-Band)
Z-Line
Other names of Z-line
Zwischenscheiben Line; Z-band; Z-disc
Z-line to Z-line
Sarcomere
Repeating units which make up Myofibrils
The repetitive functional subunit of the contractile apparatus
Sarcomere
lighter zone in center of A-Band
H-Band
Other names for H-Band
Henle’s Band; Heller Band; Hell Band; Henson’s Band
thin, dark band which bisects the H-Band
M-Line
Other name for M-line
Mittelscheibe Line
contract at slower rate but capable of continuous contraction
Red (Slow Twitch) Muscle
do not fatigue easily
Red
richer blood supply
Red
high content of red pigments (Myoglobin and Mitochondrial Cytochromes)
Red
many mitochondria
Red
smaller in diameter
Red
contract rapidly but briefly
White (Fast Twitch) Muscle
fatigues fast
White
low Myoglobin content
White
fewer Mitochondria
White
large in diameter
White
Slow, Oxidative Fibers
- ATP from Oxidative phosphorylation
Type I
Fast, Oxidative-Glycolytic Fibers
- ATP from Oxidative phosphorylation
Type IIA
Fast, Glycolytic Fibers
- ATP from ANaerobic glycolysis
Type IIB
Uni/ binucleated
Striated
Branching
Involuntary
Cardiac Muscle
unique in cardiac muscles
INTERCALATED DISCS
Elongated
Individual fibers
Single, ovoid, & centrally-located nucleus
Shape: spindled w/ tapered ends
Smooth Muscle
Distinctive characteristic of Skeletal Muscle
Peripheral nuclei
Distinctive characteristic of Cardiac Muscle
Intercalated disc
Distinctive characteristic of Smooth Muscle
No Striations