Bio Ch.10

Identify the molecules pictured in the neuromuscular junction:

A- moves in the axonal terminal / calcium ions B-Moves into the sarcoplasm /sodium ions C-moves across the synaptic gap / acetylcholine D-moves out of the sarcoplasm / potassium ions

A cord like structure that attaches a muscle to a bone is a -?

tendon

In a sarcomere, the m line serves as an attachment site for the - filaments and keeps them aligned during contraction and relaxation.

thick

As you sit there reading this your muscles, even your relaxed ones are not completely relaxed and soft. This is because they have some background tension called resting muscle -?

tone

Identify each type of muscle contraction pictures:

A-isometric B-Concentric isotonic C-Eccentric isotonic

At maximal contraction of a muscle fiber, the thin filaments are pulled into the - zone which disappears?

H

Match the muscle tissue with its conduction speed.

Skeletal-fast Cardiac-moderate Smooth-slow

Match the muscle tissues with its appearance of shape.

Skeletal-long,cylindrical fiber cardiac-short,branched cell smooth-fusiform shaped cell

To start a muscle contraction, a nerve impulse causes - release at a neuromuscular junction?

acetylcholine

In a neuromuscular junction, the enzyme - breaks down actylcholine?

actylcholinesterase

Ten minutes into a marathon, your body is relying on - cellular respiration for ATP?

aerobic

Cardiac muscle cells are - and contain - nuclei?

branched 1-2

A muscle fiber is what level of organization in the body?

cellular

The enzyme acetylcholinesterase resides in the synaptic -?

cleft

As a result of muscle fiber contraction, thick filaments in neighboring sarcomeres move -?

closer together

In - tetany, a muscle cell is stimulated so frequently that it is not allowed to relax at all between stimuli?

complete

After exposure of the active sites on actin, myosin heads attach to the actin and form -?

cross bridges

Myosin head attachment and pivoting do not require energy, but ATP is needed for the myosin head cross bridge to - from actin and re cock?

detach

After a contraction, muscle returns to its original relaxed position due to it's natural -?

elasticity

The synaptic knob of the neuron is a - of an axon?

expanded tip

In a transverse section of a muscle, you can see that each skeletal muscle is actually composed of many - which are bundles of muscle fibers?

fascicles

Which are characteristics of oxidative fibers?

good for endurance high concentration of myoglobin red use aerobic respiration

Cardiac muscle cells form Y shaped branches and join to adjacent muscle cells at junctions called - discs?

intercalated

Eccentric contractions actively - a muscle?

lengthen

In a motor unit, a single - neuron typically controls numerous muscle fibers in a muscle?

motor

Skeletal muscle fibers are -?

multinucleate

Match the muscle component with its description.

muscle- multiple bundles fascicle-a bundle of muscle muscle fiber-elongated, myofibril-long myofilament-short

Muscle fibers that rely on aerobic respiration for ATP synthesis contain a high concentration of - which gives them a reddish appearance?

myoglobin

The point where a motor neuron meets a skeletal muscle fiber is called the - junction?

neuromuscular

As you hold a barbell and begin to flex your arm in a curl, your biceps brachii slowly lifts the weight by using more and more motor units. This phenomenon, which increases the strength of the contraction, is referred to as -?

recruitment

Slow fibers or type 1 fibers are also called - fibers because they contain the pigment myoglobin?

red

The motor end plate is a specialized region of the -?

sarcolemma

The functional contractile unit of a skeletal muscle fiber is known as a -?

sarcomere

Within a myofibril, each - shortens as the muscle fiber contracts?

sarcomere

The cytoplasm of skeletal muscle cell has a specific name and is known as -?

sarcoplasm

If a skeletal muscle is injured, surrounding - cells may be stimulated to differentiate and assist in its repair and regeneration?

satellite

Which is not a connective tissue component of a muscle?

skeletal muscle fibers

The epimysium of a muscle surrounds -?

the entire skeletal muscle

When calcium ions bind to troponin, which of the following the occurs?

the myosin binding sites on actin are exposed

True or false: Smooth muscle cells lack transverse tubules.

true

Each myosin protein molecule in a thick filament consists of - strands?

two

Within a synaptic knob, synaptic - contain the neurotransmitter ACh?

vesicles

Match the name of the component of a muscle fiber with its description.

Sarcolemma-Plasma membrane of a muscle fiber muscle fiber-a muscle cell sarcoplasm-cytoplasm of a muscle fiber sarcoplasmic reticulum-smooth endoplasmic reticulum in a muscle fiber T tubule- Narrow, tubular extensions of the sarcolemma into the sarcoplasm

A muscle cell obtains ATP in the short term via what process?

anaerobic respiration

When a muscle fiber contracts, which parts of the sarcomere maintain a constant length throughout contraction?

A band

Identify the myofilament proteins in the picture. B is pointing to a green strucutre.

A-myosin B-tropomyosin C-g actin D-troponin

Match each structure in the diagram with its name:

A-sarcolemma B-myofibril C-sarcomere D-myofilaments

Identify each structure in the diagram:

A-sarcomere B-titin C-thin filament D-thick filament

According to the sliding filament theory, the length of - band remains constant, but the - zone disappears?

A/H

Blood vessels deliver nutrients and oxygen to the muscle fibers so that they can produce the molecule - which is needed for contraction?

ATP

Energy to drive the myosin movement in the sliding filament process is provided in the form of -?

ATP

The endomysium is composed of what type of connective tissue?

Areolar

Match each stage of muscle twitch with the amount of tension generated.

Latent period-there is no tension contraction period-tension increases relaxation period- tension decreases

The three connective tissue layers surrounding the individual components of a muscle are the : - - and -?

epimysium perimysium endomysium

Muscle cells are said to have what characteristic because they can respond to stimulation from the nervous system?

excitability

Place the events in the diagram in order.

1-Nerve impulse arrives at synaptic knob 2-Ca2 enters and binds synaptic vesicles 3-ACh is released into synaptic cleft 4-ACh binds receptors on the motor end plate