Ch 10 Muscle tissue Flashcards
what are skeletal muscles
muscles that are attached to the skeletal system
This allows us to move
what are the 5 functions of the skeletal muscles
- to produce movement
- maintain posture or body position
- support soft tissues
- guard the entrances and exits of the body
- maintain body temp by generating body heat
At each end of the muscle the collagen fibers of the epidymiusm parimysium and endomymysuim come together to form a
Tendon
Muscle tissue one of the four basic tissue groups consists chiefly of cells that are highly specialized for
Contraction
In response to action potentials arriving along the transverse tubules the sarcoplasmic reticulum releases
Calcium ions
Since each myofibril is attached at either end of the muscle fiber when sarcomeres shorten the muscle fiber
Shortens
Each skeletal muscle fiber is controlled by a motor neuron at a single
Sarcomere
The plasma membrane of a skeletal muscle fiber is called
Sarcolemma
The repeating unit of a skeletal muscle fiber is the
Sarcomere
The region of the sarcomere that always contains thin filaments is the
iBand
A resting muscle generates most of its ATP by
Aerobic metabolism
Which of the following types of muscle fibers are best adapted for prolonged contractions such as standing all day
Slow fibers
Thin filaments are mostly made of the protein
Actin
The region of the sarcomere containing the thick filament is the
H band
The increase in muscle tension that is produced by increasing the number of active motor units is called
Recruitment
How would an elevated level of thyroid hormone in the body affect skeletal muscles
It would stimulate energy use in heat production
The bundle of collagen fibers at the end of a skeletal muscle that attaches muscle to bone is called a
Tendon
Repeating unit of striated myofibrils
Sarcomere
When calcium ion binds to troponin
Tropomyosin rolls away from the active site
After death muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm this results in a condition known as
Rigor mortis
The area of the a band that contains no thin filaments is the
H band
When a skeletal muscle fiber contracts the zones of overlap get
Larger
During the time when the action potential moves through the sarcolemma a muscle twitch is in
Latent period
Because the cells of skeletal muscle are relatively large and cylindrical in shape, they are also known as __________.
fibers
Skeletal muscle cells have more than one nucleus.
True
Each muscle cell is surrounded by thin connective tissue called the __________.
endomysium
A cordlike structure that connects a muscle to another muscle or bone is __________.
a tendon
The neuron and muscle fiber membranes do NOT actually touch but are separated by a fluid-filled gap
True
The contractile unit of muscle is the __________.
sarcomere
What process directly inhibits acetylcholine (ACh) release after a Botox® injection?
exocytosis
A muscle fiber is ________.
a muscle cell
What is the correct order of structures as you move from outside a muscle cell, to deep inside it?
fiber, myofibril, myofilament
The actual contractile units of muscles extend from Z disc to Z disc. They are ________
sarcomeres
This contractile protein forms the thin filaments.
actin
This contractile protein is shaped like a golf club.
myosin
The dark band of skeletal muscle consists of ________
both thick and thin filament
This indentation of the sarcolemma carries electrical signals deep into the muscle cells.
T tubule
From gross to microscopic, the parts of a muscle are _______
muscle, fascicle, fiber
Each of the elements that make up a skeletal muscle is surrounded by connective tissue. Which words below correctly pair the connective tissue layer with the corresponding muscle structure?
fascicle: perimysium
This strong, cord-like structure attaches muscles to bones.
tendon
The neuromuscular junction consists of ________.
the axon terminal coming into close proximity to a muscle fiber
The space between the axon terminal and the sarcolemma of a muscle fiber is called the ________.
synaptic cleft
A neuron and all the muscle fibers it stimulates is called a ________
motor unit
Sarcomeres consist of ________.
orderly arrangements of actin and myosin
The thick and thin filaments are made up of ________, respectively.
myosin and actin
An aponeurosis is ________.
similar to a tendon in function
The function of the neuromuscular junction is to ________.
convey a signal from the nervous system to skeletal muscle
At the neuromuscular junction, the electrical signal of the nerve ________
causes the axon terminal to release acetylcholine (ACh)
Acetylcholine (ACh) is the neurotransmitter of axon terminals at the neuromuscular junction. It ________
binds to receptors on the muscle membrane
The I-band consists of ________
thin filaments
A triad consists of ________.
terminal cisternae and T-tubules
