Biol 2101 Lab Final
Fascicle(2)
surrounded by perimysium
Sarcoplasmic reticulum
tubular network wrapped around each myofibril
Endomysium(2)
Encases individual muscle fibers
Perimysium(1)
Fibrous connective tissue rich in collagen and elastin
Aponeurosis
If tendon is a broad sheet
Epimysium(2)
Rich in collagen fibers
Contains only thick filaments
A band contains only
Fascicle(1)
A bundle of muscle fibers within a muscle
Cardiac muscle cells
Branched fibers
Depolarized
Ca2+ released into muscle fiber when
Muscle contraction
Ca2+ released triggers
Transverse tubule
Carries wave of depolarization throughout muscle fiber
Thin myofilament
composed primarily of actin
I band
Z disc is in middle of
Muscle fiber(1)
a single multinucleate muscle cell
neuromuscular junction
point of contact between a motor neuron and a skeletal muscle cell
Axon of motor neuron
carries wave of depolarization to muscle
Sarcomere
functional subunit of myofibril
Synaptic vesicles
fuse with plasma membrane of axon terminal to release ACh into synaptic cleft
Tendon(3)
heavy in collagen fibers
Epimysium(3)
Surrounds entire muscle
Thick myofilament
composed primarily of myosin
M line
connects thick filaments down center of sarcomere
Endomysium(4)
connects together adjacent muscle fibers within the fascicle
sarcoplasmic reticulum
contains high Ca2+ concentration
motor end plate
contains membrane receptor proteins that bind acetylcholine
Synaptic cleft
contains molecules of the enzyme actylcholinesterse (AChE)
H zone
contains only thick filaments
thick and thin myofilaments
creates banded pattern within sarcomere
Myofibril
cylindrical subunit of muscle fiber
Perimysium(2)
divides muscle into compartments called fascicles
Z disc
end line of a sarcomere
Sarcomere
extends from Z disc to Z disc
motor end plate
forms muscle side of neuromuscular junction
Transverse tubule
forms network through muscle fiber
Axon terminal
forms neuron side of neuromuscular junction
I band
light region at each end of sarcomere
H zone
lighter region around M line
Synaptic vesicles
located at tip of axon terminal
Synaptic cleft
narrow space between axon terminal and motor end plate
Sarcolemma
plasma membrane of a muscle fiber
NA+ rushes into muscle fibers, which may depolarize the sarcolemma
when ACh is bound to receptors,
Contains only thin filaments
I band contains only
Sarcomere
I band, A band, H zone, M line, Z disc
Tendon(1)
Rope-like bundle of dense regular connective tissue
Smooth muscle cells
Single, nucleated cells
Synaptic cleft
AChE breaks down ACh to remove it from the
Myofibril
Consists of series of sarcomeres
Synaptic vesicles
Contain neurotransmitter, acetylcholine (ACh)
Endomysium(3)
Contains capillaries and neurons associated with its muscle fiber
Transverse tubule
Continuous with sarcolemma
Axon Terminal
distal portion of a motor neuron
Myofibril
Appears banded under microscope due to arrangement of myofilaments
Tendon (4)
Attaches muscle to bone
Epimysium(1)
Dense layer of connective tissue
Perimysium
Layer surrounding fascicle (bundle of fibers)
Endomysium
Layer surrounding individual muscle fibers
Skeletal muscle cells
Linearly arranged sarcomeres
Tendon(2)
Located at the ends of muscle
Perimysium(3)
Nerves and blood vessels run through muscle in this layer of connective tissue
Epimysium
Outermost layer- merges with tendon/aponeurosis
Sarcomere
Overlapping thin and thick filaments slide past each other to produce contraction
Z disc
Thin filaments anchored to it
Skeletal muscle cells
Unbranched fibers
Skeletal muscle cells
Voluntary
Muscle fiber(2)
Wrapped in endomysium
Axon of motor neuron
branch of efferent motor neuron
Endomysium(1)
delicate connective tissue layer
A band
dense central region of sarcomere
Mitchondria
produce ATP to power muscle contraction
