Human A&P 3

Which of the following individuals would have more mitochondria in her skeletal muscle?

A 22-year-old soccer player

If acetylcholinesterase became mutated and nonfunctional, what would be the immediate result?

Acetylcholine would build up in the synaptic cleft.

Name the arm muscle labeled 3.

Biceps brachii

If a drug was developed that interfered with the proper functioning of the microtubules found within the axons of neurons, how would you expect this to impact axonal transport processes?

Both anterograde and retrograde transport processes would cease.

Which statement about the nervous and endocrine systems is true?

Both systems are dedicated to maintaining stable internal conditions by detecting and responding to stimuli.

Name the arm muscle labeled 4.

Brachialis

At the synaptic knob, voltage-gated ______________ channels open, thereby stimulating the synaptic vesicles to release their neurotransmitters by exocytosis.

Calcium

The enzyme choline acetyltransferase catalyzes the reaction between acetyl-CoA and choline resulting in the formation of the neurotransmitter acetylcholine. This enzyme is produced within the cell body of neurons, but the synthesis of acetylcholine occurs within the axon terminals. Which statement best describes the axonal transport mechanism associated with this process?

Choline acetyltransferase is transported in the anterograde direction.

A dark band formed by parallel thick filaments that partly overlap the thin filaments is known as an H band.

False

What is the action of the flexor digiti minimi bevis?

Flexes the smallest finger

In an action potential, which event directly follows repolarization?

Hyperpolarization of the membrane

An inhibitory local potential causes which of the following?

Hyperpolarization of the plasma membrane

Choose the correct statement about myelin.

It is best not to give children under two years of age a low-fat diet because myelin formation requires lipids.

In skeletal muscles, which of the following is true regarding the calcium needed for contraction?

It is stored in the sarcoplasmic reticulum.

Name the arm muscle labeled 2.

Lateral head of triceps brachii

Acetylcholine has which effect on the postsynaptic neuron?

Ligand-gated sodium ion channels open and sodium diffuses in.

Name the arm muscle labeled 1.

Long head of triceps brachii

Why does depolarization occur?

More sodium ions diffuse into the cell than potassium ions diffuse out of it.

The study of the muscular system is known as __________.

Myology

During depolarization, which of the following statements about voltage-gated ion channels is true?

Na+ gates open before K+ gates

Name the part of the neuron labeled 4.

Node of Ranvier

______________ the time between signals sent from the same presynaptic terminal increases the strength of the graded potential. This is an example of ________________ summation.

Reducing; temporal

Which of the following is an accurate comparison of skeletal muscle to smooth muscle?

Smooth muscle contracts and relaxes more slowly.

Name the part of the neuron labeled 2.

Soma

What happens as a result of ion flow at a presynaptic terminal?

Synaptic vesicles migrate to the plasma membrane and release acetylcholine.

Which of the following statements about the resting membrane potential is true?

The exterior of the cell has a net positive charge, and the interior has a net negative charge.

What is acetylcholine?

The neurotransmitter released at a neuromuscular junction

Which of the following structures is not found in the shoulder?

The radioulnar ligament

The resting membrane potential is negative due to which of the following?

There are more negatively charged particles on the inside of the membrane than on the outside.

Which of the following is true of interneurons?

They are contained entirely within the CNS and carry signals from one neuron to another.

Extensibility refers to the ability of a muscle to stretch.

True

The sarcoplasmic reticulum is the smooth endoplasmic reticulum of a muscle fiber.

True

Indicate the summative effect that brings the initial segment closest to threshold.

Two EPSPs in proximity to each other

An action potential arriving at the presynaptic terminal causes what to occur?

Voltage-gated calcium ion channels open, and calcium ions diffuse into the cell.

Which of the following marks the boundaries of a sarcomere?

Z discs

Raising an arm to one side of the body to stop a taxi is an example of __________ of the shoulder.

abduction

A cholinergic synapse uses __________ as its neurotransmitter.

acetylcholine

Which of the following muscles is in the medial compartment of the thigh?

adductor longus

What term best describes the relationship between the pronator quadratus and supinator?

antagonists

The study of joint structure, function, and dysfunction is called __________.

arthrology

The smooth, connective tissue lining that covers the opposing bony surfaces of a synovial joint is called __________.

articular cartilage

What type of cell is labeled 1 in this figure?

astrocyte

The term "nerve fiber" refers to a(n) __________.

axon

Substances that cause facilitation of a neuron _________________.

cause the neuron to fire that may not under the same circumstances in the absence of the facilitator

A resting membrane potential of -70 mV indicates that the ________________.

charges lining the inside of the plasma membrane are negative compared to the charges lining the outside

The opening of __________ gates produces an __________.

chloride; IPSP

Name the part of the neuron labeled 1.

dendrites

Where do most local potentials form in a neuron?

dendrites

In a neuron, the opening of sodium gates typically leads to __________.

depolarization of the plasma membrane

What is the action of the depressor labii inferioris?

depresses lower lip

Which one of these muscles helps to open the mouth (depress the mandible)?

digastric

Which of the following is not a major joint category?

elastic

What type of cell is labeled 2 in this figure?

ependymal cell

Name the layer of connective tissue labeled 2.

epimysium

What is the opposite of presynaptic inhibition?

facilitation

Groups of muscles are separated by which of the following?

fascia

Name the layer of connective tissue labeled 1.

fascia

Muscle fibers are arranged in bundles called ___________.

fascicles

Raising your hand and placing it on the shoulder of a person standing in front of you, requires __________ of the shoulder.

flexion

Which of the following are effectors?

glands

Showing your palm to someone who is in front of you, as if to tell them "Stop," requires __________.

hyperextension of the wrist

About 90% of the neurons in the nervous system are __________ neurons.

inter

Name the parts of the axon labeled 5.

internodes

Graded potentials result from the opening of ________________.

ligand-gated channels

Athletes who train at high altitudes increase their red blood cell count, which increases their oxygen supply during exercise. Increased oxygen supply results in __________.

longer aerobic respiration

Name the facial muscle labeled 4.

masseter

The ________ attaches to the zygomatic arch and also to the angle of the mandible.

masseter

What type of cell is labeled 5 in this figure?

microglia

Why does depolarization occur?

more Na+ diffuse into the cell than K+ diffuse out of it

What type of cell is labeled 3 in this figure?

neuron

Assume in a laboratory you were able to isolate a neuron and remove the Acetylcholine receptors from the postsynaptic membrane. The substance _________________ would no longer cause facilitation of this neuron.

nicotine

During the absolute refractory period which of the following is true?

no stimulus of any strength will trigger a new action potential

Name the part of the neuron labeled 3.

nucleus

What type of cell is labeled 4 in this figure?

oligodendrocyte

Which cells form myelin in the spinal cord?

oligodendrocytes

Which of the following is most likey to cause a rapid depolarization?

opening of sodium channels

Name the facial muscle labeled 1.

orbicularis oculi

Name the facial muscle labeled 5.

orbicularis oris

Nerves are __________ of the nervous system.

organs

The rectus femoris is an example of what muscle shape?

pennate

Name the layer of connective tissue labeled 3.

perimysium

Which connective tissue layer bundles muscle fibers together into fascicles?

perimysium

The proximal radioulnar joint is a __________ joint.

pivot

Which of the following is not a characteristic of a muscle cell?

plasticity

An inhibitory postsynaptic potential results from the opening of____________________.

potassium and/or chloride channels

Why does repolarization occur?

potassium ions continue to diffuse out of the cell after the inactivation gates of the voltage-gated sodium ion channels begin to close.

Graded potentials are produced within the _______________________ segment of a neuron.

receptive

Suppose that a new virus is discovered that specifically infects motor neurons. Assume that this virus enters neurons in conjunction with choline molecules. Once inside the cell, the virus enters the nucleus and replicates. Which direction describes the axonal transport route taken by this virus?

retrograde transport

The joint between the left and right parietal bones is called the __________.

sagittal suture

Which of the following is not a function of the muscular system?

secretion

Coronal, sagittal, and lambdoid are examples of __________.

serrate sutures

Normally, sodium and potassium leakage channels differ because

sodium ions diffuse through leakage channels into the cell, but potassium ions diffuse through leakage channels out of the cell

The skeletal muscles are innervated by __________.

spinal nerves and cranial nerves

In skeletal muscle, the term that describes the alternating light and dark bands is ___________.

striations

The __________ division tends to prepare the body for action.

sympathetic

The joint between the L2 and L3 vertebrae is a __________.

symphysis

The least movable joints are _____________ joints.

synostosis

The most movable joints are ___________ joints.

synovial

Why does hyperpolarization occur?

the increased potassium ion permeability lasts slightly longer than the time required to bring the membrane potential back to its resting level.

Which of these muscles attaches to both the thyroid cartilage of the larynx and to the hyoid bone?

thyrohyoid

The deepest muscle of the abdominal wall is the __________.

transverse abdominal

The __________ division carries signals to the smooth muscle in the large intestine.

visceral motor

What is another name for the autonomic nervous system?

visceral motor division

Because skeletal muscle is under the conscious control, it is said to be what?

voluntary

Skeletal muscle is called ___________, because it is usually subject to conscious control.

voluntary

Name the facial muscle labeled 3.

zygomaticus major

Name the facial muscle labeled 2.

zygomaticus minor