Ch. 9 Muscle Tissue Flashcards
Which is the correct description of Deep Fascia?
1) Surrounds the entire muscle
2) Lies between neighboring muscle
3) Surrounds each fiber
4) Surrounds each bundle (fascicle)
Lies between neighboring muscles
Which of the following is not a characteristic of skeletal muscle?
1) It can contract for long periods without tiring
2) It can exert tremendous power
3) It contracts rapidly
4) It is voluntary
It can contract for long periods of time without tiring
Ability of a muscle to resume its resting length after being stretched.
Elasticity
What is the sheet-like indirect attachment that anchors a muscle?
Aponeurosis
Which describes Endomysium?
1) Surrounds each bundle (fascicle)
2) Surrounds each muscle fiber
3) Binds muscles to other muscles
4) Surrounds an entire muscle
Surrounds each muscle fiber
Which describes Perimysium?
1) Surrounds each bundle (fascicle)
2) Surrounds each muscle fiber
3) Binds muscles to other muscles
4) Surrounds an entire muscle
Surrounds each bundle (fascicle)
Which of the following is a special adaptation present in skeletal muscle cells, but absent in most other cells?
1) Muscle cells have myoglobin
2) Muscle cells have mitochondria
3) Muscle cells have a nucleus
4) Muscle cells use ATP
Muscle cells have myoglobin; most other cells do not
Myofibrils are composed of repeating contractile elements called ?
Sarcomeres
The linking of thick and thin filaments together is called ?
Forming a cross bridge
What is the area of the sarcomere with overlapping thick and thin filaments?
A band
The thin myofilaments of skeletal muscle are composed chiefly of ?
Actin
What is the oxygen storage molecule in skeletal muscle?
Myoglobin
A sarcomere is part of a ?
Myofibril
Which of the following allows recoil of the muscle fiber when contraction ends?
1) Elastic filament (titin)
2) Thin filament (actin)
3) Thin filament (tropomyosin)
4) Thin filament (troponin)
5) Thick filament (myosin)
Titin
“Cross bridges” that link between the thick and thin filaments directly involve ?
Myosin
In the sliding filament model of contraction, what occurs when the muscle cell shortens?
The distance between successive Z discs shortens.
What is the rod-like contractile element within a muscle fiber containing myofilaments.
Myofibril
What is the plasma membrane of skeletal muscle fiber?
Sarcolemma
In the sliding filament model of muscle contraction, the myofilaments slide over each other, resulting in the overlapping of actin and ?
Myosin
The functional unit of contraction in a skeletal muscle fiber is the ?
Sarcomere
What is the area in the center of the A band containing only thick filaments?
H zone
What is the description of ion movement at the neuromuscular junction that produces the end plate potential?
More sodium enters the muscle fiber than potassium leaves the muscle fiber.
What is End Plate Potential?
Depolarization occurring only at the neuromuscular junction
Give the description of the voltage-gated ion channels for a region of sarcolemma that is undergoing repolarization.
Sodium channels close and potassium channels open
Give the description of the voltage-gated ion channels for a region of sarcolemma that is undergoing depolarization.
Sodium channels are open and potassium channels are closed
What is the action of Troponin?
Binds Ca2+ and starts the contraction cycle
Which of the following is an autoimmune disease that destroys acetylcholine receptors?
Myasthenia gravis
Does calcium bind to myosin heads during muscle contraction?
False; ATP binds to myosin heads
What ion combines with troponin, causing troponin to change shape which removes the blocking action of tropomyosin, allowing cross bridges to form.
Ca++
What best describes the composition of the structure known as a triad in a skeletal muscle fiber?
Terminal cisterna, transverse tubule, and terminal cisterna
The type of muscle contraction in which the muscle fibers produce increased tension although the muscle neither shortens nor lengthens is called ______.
Isometric
Smooth muscle fibers appear ___ shaped.
Spindle
What substance increases in quantity during repetitive muscle contraction during oxygen deficit?
Lactic acid
What substances all decrease during muscle contraction?
ATP, Creatine phosphate, Glucose, and Oxygen
Which one of the following binds calcium ions in a smooth muscle, causing contraction?
1) Troponin
2) Calmodulin
3) Myosin
4) Actin
Calmodulin
____ is the ability of a muscle to shorten forcibly when adequately stimulated.
Contractility
During the phase of excitation-contraction coupling of skeletal muscle, what occurs immediately after the action potential spreads down the T tubule?
The sarcoplasmic reticulum releases calcium.
Glycogen stores are abundant in ____ ____ fibers.
Fast glycolytic
Myofilament cross bridges form when which two structures bond?
Myosin heads and globular actin
What is the cause of rigor mortis?
Calcium influx into the sarcoplasm after death
____ is the term used to describe the squeezing action produced when opposing layers of smooth muscle alternate contraction and relaxation.
Peristalsis
One T tubule lies between two ?
Terminal cisternae