Chapter 10: Muscle Tissue

________ released from the sarcoplasmic reticulum bind to troponin to trigger exposure of binding sites on actin and begin the contraction cycle. ______ supplies energy to detach the myosin head from actin. -Calcium ions; ATP -Calcium ions; Titin -Sodium ions; ATP -Sodium ions; GTP

Calcium ions; ATP

Which of the following is directly responsible for transmitting an action potential from a motor neuron to a skeletal muscle fiber? -creatine phosphate -acetylcholine -myofibrils -gap junctions -intercalated discs

acetylcholine

A runner nearing the end of a marathon race would produce most ATP by: -aerobic respiration. -anaerobic respiration. -creatine phosphate. -amino acid breakdown.

aerobic respiration

The site where a somatic motor neuron releases acetylcholine to stimulate a skeletal muscle fiber is called the -neuromuscular junction -synaptic end bulbs -motor end plate -myofibril -sarcolemma

neuromuscular junction

Skeletal muscle is covered, surrounded and protected by various layers of connective tissue. Which layer of connective tissue would surround a bundle of muscle fibers (muscle cells)? -hypodermis -endomysium -epimysium -fascia -perimysium

perimysium

In a neuromuscular junction, the effect of acetylcholine (ACh) binding to receptors on the motor end plate lasts only briefly due to -endocytosis of the ACh receptor into the myofiber. -diffusion of the ACh out of the synaptic cleft. -rapid uptake of the ACh into the myofiber. -rapid destruction of ACh in the synaptic cleft by monoamine oxidase. -rapid destruction of ACh in the synaptic cleft by acetylcholinesterase.

rapid destruction of ACh in the synaptic cleft by acetylcholinesterase

Which type of muscle tissue is involuntary (can't be consciously controlled)? -skeletal muscle -smooth muscle -cardiac muscle -skeletal muscle and smooth muscle -smooth muscle and cardiac muscle

smooth muscle and cardiac muscle

Skeletal muscle contraction is triggered to begin when calcium is released from -mitochondria -T-tubules -terminal cisterns of sarcoplasmic reticulum -myofibrils

terminal cisterns of sarcoplasmic reticulum

Which protein does calcium bind to? -tropomyosin -troponin -myosin -actin

troponin

Through aerobic respiration in the mitochondria, one glucose molecule can create -2 ATP -4 ATP -30 or more ATP -None of these

30 or more ATP

What energizes the myosin head? -Phosphate release -calcium ions -ATP hydrolysis reaction -ADP synthesis -acetylcholine

ATP hydrolysis reaction

Muscular tissue has several important properties, such as electrical excitability. Another property of muscular tissue is that it is able to stretch, and return to its original size and shape. Which property of muscular tissue is this? -Conductivity -Elasticity -Extensibility -Plasticity -None of these is correct

Elasticity

Myasthenia Gravis is an autoimmune disorder that targets the ACh receptors at the NMJ and ultimately reduces the number of available receptors. Predict what happens if you treat the patient with a drug that inhibits the activity of acetylcholinesterase? -The drug will increase contraction. -The drug will cause spasm -The drug will prevent contraction. -The drug will cause a weak contraction.

The drug will increase contraction.

Muscle fibers produce ATP using: -creatine phosphate. -anaerobic cellular respiration. -aerobic cellular respiration. -all of the choices are correct.

all of the choices are correct

The general functions of muscle tissue include: -production of body movement. -stabilization of body positions. -storage and movement of substances through the body. -heat generation. -all of the choices are correct

all of the choices are correct

Which ATP production would be sufficient to run in place for one minute? -creatine phosphate -anaerobic cellular respiration -aerobic cellular respiration

anaerobic cellular respiration

Which correctly lists the sequence of structures that action potentials must move through to excite skeletal muscle contraction? -axon of neuron, sarcolemma, T tubules -T tubules, sarcolemma, myofilament -myofibrils, myofilaments, mitochondria -muscle fiber, axon of neuron, myofibrils -sarcolemma, axon of neuron, T tubules

axon of neuron, sarcolemma, T tubules

Contraction of myofibrils within a muscle fiber begins when -sodium enters the muscle fiber -calcium is released from the sarcoplasmic reticulum -acetylcholine binds to ligand gates -an action potential travels t-tubules -calcium is moved into the sarcoplasmic reticulum

calcium is released from the sarcoplasmic reticulum

The outermost layer of connective tissue surrounding a skeletal muscle is the -ligament -perimysium -endomysium -epimysium -tendon

epimysium

Which property of muscle gives it the ability to stretch without damage? -extensibility -elasticity -electrical excitability -contractility

extensibility

When a person is hooked up to a machine that will record myograms, a record of their muscle activity can be produced (depending on the frequency and strength of the stimuli that generate an action potential in their muscle tissue). If the person receives a series of multiple stimuli in a short period of time, the wave of muscle activity that will be recorded will show a sustained contraction with no period of relaxation in between the periods when they receive the stimuli. The myograms has recorded: -an incomplete twitch -a fused (complete) twitch -fused (complete) tentanus -incomplete tetanus -an extended muscle spasm

fused (complete) tentanus

After the fusion of myoblasts, the muscle fiber loses its ability to -go through mitosis -lengthen -contract -grow

go through mitosis

Which term describes a somatic motor neuron and all the skeletal muscle fibers it stimulates? -neuromuscular junction -motor end plate -synapse -motor unit

motor unit

Which of the following molecules found in skeletal muscle cells binds oxygen that can later be used during aerobic metabolism to help generate ATP? -myoglobin -creatine -creatine phosphate -glycogen -titin

myoglobin

During the contraction cycle, ATP attaches to -actin -troponin -myosin -tropomyosin -none of these choices

myosin

Cross bridges are formed during muscle contraction when _____ binds to _____. -actin; troponin -myosin; troponin -myosin; actin -actin; myosin -actin; tropomyosin

myosin; actin

Mitochondrial activity in skeletal muscle cells are usually efficient, but can have limited ATP production if -there is pyruvic acid accumulation. -there is limited O2 availability -CO2 is produced as a waste product.

there is limited O2 availability

Creatine phosphate reserves are restored via phosphorylation by ATP during rest. -True -False

true

Energy can be transferred in the muscle cell through the conversion of ATP into ADP. -True -False

true

In motor unit recruitment, the number of active motor units increases. -True -False

true

A brief contraction of all muscle fibers in a motor unit in response to a single action potential moving down the somatic motor neuron is known as -unfused tetanus -refractory period -twitch contraction -wave summation -fused tetanus

twitch contraction