unit 8 test review

Which number most closely approximates the number of skeletal muscles in the human body? -about a 1,000 -206 -650 -several thousand

650

used to help myosin heads release from actin

ATP

what substance must bind to myosin heads in order for the heads to detach from the thin filaments

ATP

Which of the following statements is NOT true of skeletal muscle activity? -All muscles have at least two attachments. -During contraction, the muscle origin moves towards the insertion. -The bulk of the muscle lies proximal to the joint crossed. -Typically, muscles cross at least one joint.

During contraction, the muscle origin moves towards the insertion

Which of the following statements is NOT true? -A strong contraction results when all motor units are stimulated -How forcefully a muscle contracts depends on how many cells are stimulated -Graded muscle contractions may be produced by changing the frequency of muscle stimulation. -The all-or-none law states that muscles may contract completely, partially, or not at all when stimulated

The all-or-none law states that muscles may contract completely, partially, or not at all when stimulated

Which of the following statements is NOT true? -Contractility refers to the muscles ability to shorten -Isotonic contractions result in sliding myofilaments and muscle movement -When a muscle relaxes, it pushes on the insertion -Muscles can only pull

When a muscle relaxes, it pushes on the insertion

neurotransmitter released from vesicles in the motor neuron, changes the permeability of the sarcolemma

acetylcholine

A single nerve impulse produces only one contraction because

acetylcholine is broken down by acetylcholinesterase during the action potential

The sliding filament theory involves the sliding of the ___________ during skeletal muscle contraction as each cross-bridge attaches and detaches several times.

actin filaments

acetychlorine is released from the neuron's membrane in the response to

action potential

the reversal of charges along the sarcolemma

action potential

Which of the following is NOT matched correctly? -atrophy - condition of sore muscles -muscle tone - continuous partial contractions -flaccid - soft and flabby muscles -muscle soreness - result of lactic acid build-up

atrophy - condition of sore muscles

muscles need more blood than organs. which of the statements isn't true -blood needs to carry away large amounts of carbon dioxide -blood brings large amounts of ATP -blood brings large amounts of oxygen -blood carries away large amounts of latic acid -blood brings large amounts of glucose

blood brings a large amounts of ATP

Which of the following is NOT involved in supplying energy for muscle contraction? -aerobic respiration/cellular respiration -creatine phosphate -breakdown of lactic acid -lactic acid fermentation

breakdown of lactic acid

Which of the following is NOT a result of aerobic exercise on muscles? -bulging muscles -more flexible muscles -stronger muscles -greater resistance to fatigue

bulging muscles

Serves as the actual "go" signal for the muscle contraction once released from the sarcoplasmic reticulum

calcium ions

The heads of the myosin filaments are called ___________ when they link the thick and thin filaments together during skeletal muscle contraction.

crossbridges

which activity would be most dependent on creative phosphate

diving

the connective tissue sheath that covers each individual muscle fiber is ______

endomysium

The connective tissue covering that surrounds an entire muscle is

epimysium

sarco

flesh/muscle

Which of the following is NOT a function of the muscular system? -production of movement -generation of heat -hematopoiesis -stabilization of joints

hematopoiesis

which of the following is not a function of skeletal muscle -generate heat -convert chemical energy to mechanical energy -move fluids (blood, food, etc) through the body -protect internal organs

move fluids (blood, food, etc) through the body

myo or mys

muscle

a long chain of sarcomeres _____

myofibrals

Which of the following lists the structures in order from smallest to largest? -muscle fiber, fascicle, myofibril, muscle -myofilament, myofibril, fascicle, muscle fiber -myofibril, muscle fiber, muscle, fascicle -myofilament, myofibril, muscle fiber, fascicle

myofilament, myofibril, muscle fiber, fascicle

which of the following is not a component of the thin filament

myosin

acetychlorine is a ________

neurotransmitter

t-tubes are on extension of the ________

sarcolemma

which of the following is a philospholipid bilayer w/ embedded proteins

sarcolemma

when a muscle cell is at rest, most of the intracellar calcium is found stored in the _________

sarcoplasmic reticulum

how is cardiac muscle

skeletal muscle voluntary

restores resting potential

sodium potassium pump

what is the name _____

synapse

The gap between the motor neuron and the muscle fiber it supplies at the neuromuscular junction is called the _____________.

synaptic cleft

Which of the following statements about muscle tissue is NOT correct? -an individual muscle cell is called a muscle fiber -in muscle cells, the cytoplasm is called the sarcoplasm -in muscle cells, the cytoplasm is called the sarcoplasm -the sarcomere is the space between the thick and thin filaments

the sarcomere is the space between the thick and thin filaments

in a resting muscle cell the myosin binding sites are blocked by ______

tropomyosin

calcium ions bind to _________ when present to in the sarcoplasm

troponin