Muscular System - Chapter 13 Flashcards
What do smooth, cardiac, and skeletal muscle all have in common?
They are all uninucleated
They are all striated
They are all found in the walls of blood vessels
The cells of these muscles are all called muscle fibers
They all interlock at intercalated disks
The cells of these muscles are all called muscle fibers.
*The cells of all three types of muscle tissues are called muscle fibers.
(section 13.1)
Of the three types of muscle tissue, which has multinucleated fibers?
Smooth muscle
Cardiac muscle
Skeletal muscle
Both smooth and skeletal muscles
Both cardiac and smooth muscles
Skeletal muscle
*Only skeletal muscle has multinucleated fibers.
(section 13.1)
Of the three types of muscle tissue, which is voluntary?
Smooth muscle
Cardiac muscle
Skeletal muscle
Both smooth and skeletal
Both cardiac and skeletal
Skeletal muscle
*Skeletal muscle is voluntary.
(section 13.1)
Of the three types of muscle tissue, which is not striated?
Smooth muscle
Cardiac muscle
Skeletal muscle
Skeletal and smooth lack striations
Cardiac and smooth lack striations
Smooth muscle
*Smooth muscle is not striated.
(section 13.1)
Skeletal muscle contractions play a role in returning the venous blood to the heart.
True
False
True
*True, the skeletal muscle contractions play a role in returning the venous blood to the heart.
(section 13.5)
What is found within the intercalated disks of cardiac muscle?
Sarcoplasmic reticulum
Gap junctions
Dense connective tissue
Bone
Myoglobin
Gap junctions
*Gap junctions are found at intercalated disks to permit contractions to spread quickly.
(section 13.1)
Because the heart beats continuously, cardiac fibers never relax completely.
True
False
False
*Cardiac fibers relax completely between contractions, which prevents fatigue.
(section 13.1)
Which of the following is not a function of skeletal muscles?
Pumping of blood throughout the body
Support
Movement of bones
Maintenance of body temperature
Protection of internal organs
Pumping of blood throughout the body.
*Cardiac muscle makes up the heart that pumps blood throughout the body.
(section 13.1)
From the outside of a muscle coming in, the first thing encountered would be
Fascia.
Fascicle.
Dense connective tissue.
Muscle fiber.
Myofibril.
Fascia
*Muscles are covered with fascia, a type of connective tissue.
(section 13.1)
What structure attaches a muscle to a bone?
Ligaments
Tendons
Bursae
Sarcolemma
Sarcoplasm
Tendons
*Tendons connect muscles to bone. Bursae act as a cushion in the connection. Sarcolemma are the plasma membranes of a muscle fiber. Sarcoplasm is the cytoplasm of a muscle cell.
(section 13.1)
What muscle works in a pair with biceps brachii?
The triceps brachii
The trapezius
The masseter
The pectoralis major
The sartorius
The triceps brachii
*The biceps brachii and triceps brachii are a pair of antagonistic muscles.
(section 13.1)
Muscles can only pull; they can not push.
True
False
True
*Muscles can only contract and pull on the bone they are attached to.
(section 13.1)
The origin of a muscle is on a stationary bone.
True
False
True
*The origin is on the stationary bone while the insertion is on the bone that moves.
(section 13.1)
Which of the following is not a term that refers to how muscles work?
Prime mover
Synergists
Antagonists
Synergism
Origin
Synergism
*Synergism is not a term that refers to muscle movement.
(section 13.1)
What is the deltoid muscle shaped like?
A long thin line
A square
A triangle
A circle
A trapezoid
A triangle
*The Greek letter delta looks like a triangle and the deltoid is shaped like a triangle.
(section 13.1)
What does the word brevis mean when referring to a muscle?
Short
*Brevis mean short and is used to indicate the size of a muscle.
(section 13.1)
What is the name of a muscle that is responsible for blinking and winking?
Latissimus dorsi
Trapezius
Pectoralis major
Orbicularis oculi
Extensor digitorum
Orbicularis oculi
*The orbicularis oculi is around the eye and is responsible for blinking and winking.
(section 13.1)
What information does the word rectus give you about a muscle?
The size of the muscle fibers
The attachment of the muscle fibers
The action of the muscle fibers
The shape of the muscle fibers
The direction of muscle fibers
The direction of muscle fibers.
*Rectus means straight and gives information about the direction of the muscle fibers.
(section 13.1)
Which of the following does not attach to the sternocleidomastoid muscle?
Rib
Clavicle
Sternum
Mastoid process
Skull
Rib
*The sternocleidomastoid does not attach to a rib.
(section 13.1)
Which way does the adductor longus move the thigh?
Away from the midline
Toward the midline
In a circle
In a cone
Towards the back
Toward the midline
*The adductor longus adducts the thigh or moves it toward the midline. It also raises the thigh.
(section 13.1)
What is the biggest muscle (in terms of mass) in the body?
Gluteus maximus
Sartoris
Stapedius
Quadriceps femoris
Latissimus Dorsi
Gluteus maximus
*The gluteus maximus which makes up the buttocks is the largest muscle in the body.
(section 13.1)
What does the word sarco mean?
Large
Short
Muscle
Tubule
Smooth
Muscle
*The word sarco means muscle.
(section 13.2)
Several of the structures in the muscle cell are given special names. For example, the cytoplasm of a muscle fiber is called the sarcoplasm. Which of the following is truly a unique structure to muscle cells (not just a renamed one)?
Cytoplasm
Nucleus
Endoplasmic reticulum
Transverse (T) system
Plasma membrane
Transverse (T) system
*The T system is not found in other types of cells.
(section 13.2)
A muscle fiber is made up of many
Muscle cells.
T Tubules.
Myofibrils.
Fascicles.
Bursa.
Myofibrils.
*A muscle fiber is made up of many myofibrils divided into sarcomeres.
(section 13.2)
One sarcomere
Extends from Z line to Z line.
Is composed of many myofibrils.
Contains only actin fibers.
Is composed of many muscle fibers.
Surrounds each muscle in the body.
Extends from Z line to Z line.
*A sarcomere extends between two dark vertical lines called Z lines.
(section 13.2)
What ion is responsible for initiating muscle contraction?
Mg2+
Ca2+
H+
Cl-
Na+
Ca2+
*Calcium ions are released from the sarcoplasmic reticulum to initiate muscle contraction.
(section 13.2)
When a muscle contracts, the H band almost disappears.
True
False
True
*The H band is the area in the center of the sarcomere that almost disappears when the muscle contracts.
(section 13.2)
What happens to the actin and myosin filaments when a muscle contracts?
Both of them shorten.
Both of them lengthen.
Both stay the same length.
Actin shortens while myosin lengthens.
Myosin shortens while actin lengthens.
Both stay the same length.
*The actin and myosin filaments stay the same length when a muscle contracts. They just slide past each other.
(section 13.2)
What supplies the energy for muscle contractions?
Actin
Myosin
Tropomyosin
ATP
Ca^2+
ATP
*ATP supplies the energy necessary for muscle contraction.
(section 13.2)
Each actin molecule is shaped like a golf club, with a straight portion ending a globular head.
True
False
False
*Each myosin molecule is shaped like a golf club.
(section 13.2)
What does troponin bind to, and what happens when it binds?
Ca2+; tropomyosin shifts
Tropomyosin; the sarcomere relaxes
Acetylcholine; the sarcomere shortens
ATP; tropomyosin returns to normal
T tubules; the sarcomere shortens
Ca2+, tropomyosin shifts
*Troponin binds to Ca2+ and this results in a shift of the tropomyosin threads, exposing myosin-binding sites.
(section 13.2)
____________ muscle tissue is found in the walls of all your hollow visceral organs, like your stomach, and airways, and blood vessels.
Smooth
Cardiac
Skeletal
Myofibrils
Fascicles
Calcium
Smooth.
Your heart gets its very own muscle tissue type – _________ muscle, looks striped, or striated, and function involuntarily to keep your blood pumping.
Smooth
Cardiac
Skeletal
Myofibrils
Fascicles
Calcium
Cardiac
Humans have 640 __________ muscles.
Smooth
Cardiac
Skeletal
Myofibrils
Fascicles
Calcium
Skeletal
Muscle fibers form string-like bundles called ______________, which combine to form the larger rope like muscle organ.
Smooth
Cardiac
Skeletal
Myofibrils
Fascicles
Calcium
Fascicles.
In order for actin and myosin to bind and cause muscle contraction, the cells need ATP and ___________ to move troponin and tropomyosin out of the way of binding sites.
Smooth
Cardiac
Skeletal
Myofibrils
Fasciles
Calcium
Calcium.
What is found within the intercalacated disks of cardiac muscle?
Myoglobin
Sarcoplasmic reticulum
Dense connective tissue
Bone
Gap junctions
Gap junctions.
*Gap junctions are found at intercalacated disks to permit contractions to spread quickly.
One motor neuron activates one muscle fiber.
True
False
False
*One motor neuron can stimulate from a few to several muscle fibers of a muscle because each axon has several branches.
What is the name of the small gap that separates the axon terminal of a nerve from the sarcolemma?
Sliding filament
Synaptic vesicle
Synaptic cleft
Sarcoplasmic reticulum
T tubule
Synaptic cleft
*The small gap is called a synaptic cleft. The entire region is call a neuromuscular junction.
One motor unit obeys a principle called the all-or-none law.
True
False
True.
*All the muscle fibers in a motor unit are stimulated at once. They all either contract or do not contract.
What is happening during the latent period of a muscle twitch?
ADP and phosphate are released, and the power stroke of the contraction occurs.
The neurotransmitter is diffusing across the synaptic cleft, causing an electrical signal in the muscle cell.
The myosin-actin cross-bridges are broken and the sarcomere shortens.
The muscle relaxes and returns to its former length.
Fresh ATP binds to myosin, causing it to return its resting position.
The neurotransmitter is diffusing across the synaptic cleft, causing an electrical signal in the muscle.
*The latent period is the time between stimulation and initiation of contraction. During this time, the events that begin muscle contraction are occuring; acetylcholine diffuses across the synaptic cleft, causing an electrical signal to spread across the sarcolemma and down the T tubules.
Which of the following occurs when a muscle fatigues?
The muscle contracts.
Stimulation discontinues.
Acetylcholine bypasses the synaptic cleft.
Tetanus is achieved.
Its energy reserves are depleted.
Its energy reserves are depleted.
*Energy reserves are depleted during muscle fatigue.
In good muscle tone, how many motor units are contracted?
Some
5-10% of the motor units
10-15% of the motor units
None
All
Some.
*In good muscle tone, some motor units are always contracted, but not enough to cause movement.
Of the three pathways for obtaining ATP for muscle contraction, which one requires oxygen?
Fermentation and respiration.
Only respiration.
Only fermentation.
The creatine phosphate pathway and fermentation.
Only the creatine phosphate pathway.
Only respiration.
*Aerobic respiraton require a supply of oxygen. The creatine phosphate pathway and fermentation pathway do not require oxygen.
Of the three pathways for supplying ATP to the muscle, which pathway(s) do slow-twitch fibers prefer?
The creatine phosphate pathway.
The creatine phosphate pathway or fementation.
Aerobic respiration.
The creatine phosphate pathway or aerobic respiration.
Fermentation.
Aerobic respiration.
*Slow-twitch fibers prefer to use aerobic respiration for their ATP source since it produces a large supply of ATP.
Jillian is a top-level cross-country runner due to her having predominantly slow-twitch muscle fibers.
True
False
True.
*Slow-twitch muscle fibers are aerobic, have steady power, and have endurance - all required for cross-country running.
Why are slow-twitch muscles darkly colored?
They have fewer mitochondria.
They are designed for strength and explosions of energy.
They contain myoglobin.
They need less blood than fast-twitch fibers.
They have many more myofibrils per motor unit than fast-twitch fibers.
They contain myoglobin.
*Slow-twitch fibers are dark because they contain myoglobin, the respiratory pigment found in muscle cells.
Which of the following injuries is most likely to happen to the ankle?
Bursitis
Strain
Muscular dystrophy
Convultion
Sprain
Sprain
*A sprain is a twisting of the joint. A strain is the tearing of the muscle. A convultion is a seizure of the muscles. Bursitis is the inflammation of the bursa. Muscular dystrophy is a progressive degeneration of muscles.
Fibromyalgia is a temporary condition of achy muscles, usually due to overuse.
True
False
False.
*Fibromyalgia is a chronic condition with symptoms including widespread pain, tenderness and stiffness of muscles.
Leiomyomas are a type of smooth muscle cancer that occur in the uterine wall.
True
False
True.
*Leiomyomas are a type of smooth muscle cancer that occur in the uterine wall.
What is the reservoir for Ca2+ in the body?
Blood
Muscles
Liver
Brain
Bones
Bones.
*The skeleton acts as a reservoir for calcium.
What happens when the arrector pili muscles contract?
Your leg kicks out.
The blood from your skin is rerouted to your core.
The hairs on your skin stand on end.
Your head nods “yes”.
You tap your finger.
The hairs on your skin stand on end.
*The arrector pili muscles are tiny bundles of smooth muscle attached to the hair follicles that cause the hairs to stand up.
Contraction of a muscle requires all the motor units to be undergoing tetanic contraction.
True
False
False
*Some motor units are contracting maximally while others are resting, allowing sustained contractions to occur.
Which disease is an autoimmune disease characterized by weakness that expecially affects the muscles of the eyelids, face neck and extremities?
Myasthenia gravis
*These symptoms describe the disease myasthenia gravis.
What is the name of the muscle that is responsible for blinking and winking?
Orbicularis oculi
Pectoralis major
Trapezius
Litissimus dorsi
Extensor digitorum
Ocularis oculi
*The orbicularis oculi is around the eye and is responsible for winking and blinking.
What does the word brevis mean when referring to a muscle?
Short
Huge
Long
Large
Small
Short
*Brevis means short and is used to indicate the size of a muscle.
What is the difference between a tic and a spasm?
A tic refers to achy muscles, usually due to overexercise, while a spasm is just an involuntary contraction.
A tic is a spasm that can be controlled voluntarily.
A tic is a strong and very painful spasm, especially of the leg and foot.
A tic is caused by the inflammation of a tendon, while a spasm is just an involuntary contraction.
A tic is caused by stretching or tearing of a muscle, while a spasm is just an involuntary contraction.
A tic is a spasm that can be controlled voluntarily.
*A tic is a spasm that can be controlled voluntarily, but only with great effort.
