Anatomy, Chapter 11

¡Supera tus tareas y exámenes ahora con Quizwiz!

Function of Microglial Cells

- act as phagocytes

Functions of Astrocytes

- anchor neurons and blood vessels - regulate the extracellular environment - facilitate the formation of the blood-brain barrier - repair damaged tissue

Functions of Ependymal Cells

- line cavities - cilia circulate fluid around brain and spinal cord - some secrete this fluid

Function of Oligodendrocytes

- myelinate certain axons in the CNS

Function of Schwann Cells

- myelinate certain axons in the PNS

Function of Satellite Cells

- surround and support cell bodies

30. The resting membrane potential of a resting neuron is approximately

-70 mV

Assume you have a membrane with only potassium leak channels. The RMP is -90mV. Predict the RMP if we add leak channels. The most likely RMP value of is __________.

-70 mV

What is the value for the resting membrane potential for most neurons?

-70 mV

What is the value for the resting membrane potential for most neurons? a) +30 mV b) -70 mV c) -90 mV

-70 mV

what is the value for the resting membrane potential for most neurons

-70mV

What is the magnitude (amplitude) of an action potential? a) 70 mV b) 30 mV c) 100 mV

100 mV

Matched 12) Epinephrine and thyroxine cause both heart rate and cardiac output to 13) An increase in vagus nerve firing causes heart rate to 14) An increase in sympathetic nervous system firing causes cardiac output to 15) A decrease in peripheral resistance causes arterial blood pressure to 16) Aldosterone causes blood volume to 17) An increase in the deposition of saturated fats in the lining of blood vessels causes arterial blood pressure to 18) Salt causes both blood volume and arterial blood pressure to A)decrease B) increase

12) B 13) A 14) B 15) A 16) B 17) B 18) B

19) These vessels carry blood capillaries away from the heart 20) These vessels return blood to 21) Superior and inferior vena cava are classified as these types of vessels 22) The aorta is classified as one of these vessels 23) These vessels have thicker walls and a heavier tunica media 24) Nutrient and gas exchange occur in these vessels 25) Blood pressure in these vessels is low 26) These vessels have thinner walls and transport oxygenpoor blood 27) Some of these larger vessels have valves to prevent backflow 28) Venules drain these tiny B) veins C) arteries the heart

19) C 20) B 21) B 22) C 23) C 24) A 25) B 26) B 27) B 28) A

Place the events involved in the propagation of an action potential in the correct order of occurrence from left to right. 1. Axon segment depolarized to threshold 2. Local current flows to axon segment 3. Influx of Na+ 4. Voltage-gated Na+ channels open 5. AP regenerated in adjacent axon segment

2, 1, 4, 3, 5

For every ATP split into an ADP and a phosphate, the Na+/K+ pump moves __________ out of the cell and __________ into the cell. a) 3 Na+; 2 K+ b) 3 K+; 2 Na+ c) 2 Na+; 3 K+ d) 2 K+; 3 Na+

3 Na+; 2 K+

Place the events involved in generation of an action potential in the correct order of occurrence from left to right. 1. Na+ channels close, K+ channels open 2. Na+ influx, depolarization 3. Hyperpolarization, K+ channels close 4. Threshold stimulus, Na+ channels open 5. K+ efflux, repolarization

4, 2, 1, 5, 3

Order each of the following events so that they occur in the proper order with respect to the function of the channels, ion permeability, and changes in membrane potential. 1. Repolarization of the membrane 2. Depolarization of the membrane to +30 mV 3. K+ ion flow out of the neuron increases 4. Na+ ion flow into the neuron increases 5. Opening of voltage-gated Na+ channels

5, 4, 2, 3, 1

26) The average heart beats about __________ times per minute.

75

Match 9) Part of the cardiac cycle when the coronary system is emptying of blood ventricular systole 10) Part of the cardiac cycle when the bicuspid and tricuspid valves are open 11) Part of the cardiac cycle when both of the semilunar valves are closed A)ventricular systole B) ventricular diastole

9) A 10) B 11) B

Which of the following types of neurons carry impulses away from the central nervous system (CNS)? A. afferent B. association C. sensory D. motor

Motor

In which type of axon will velocity of action potential conduction be the fastest?

Myelinated axons with the largest diameter

Which of the following events will cause an EPSP? a) Ca ions exit the postsynaptic cell b) K ions exit postsynaptic cell c) Cl ions enter postsynaptic cell d) Na ions enter postsynaptic cell

Na ions enter postsynaptic cell

Depolarizing local potentials are caused by an influx of: a) Na ions via leak channels b) K ions via leak channels c) K ions via gated ion channels d) Na ions via gated ion channels

Na ions via gated ion channels

The diffusion of what ion, across the neuronal membrane, is responsible for the local currents that depolarize regions of the axon to threshold?

Na+

Which of the following is most likely to move through the cell membrane by facilitated diffusion?

Na+

The concentrations of which two ions are highest outside the cell. a) Na+ and A- (negatively charged proteins) b) Na+ and Cl- c) K+ and A- (negatively charged proteins) d) K+ and Cl-

Na+ and Cl-

During the action potential of a neuron, which ion is primarily crossing the membrane during the depolarization phase, and in which direction is the ion moving?

Na+ is entering the cell.

The Na+-K+ pump actively transports both sodium and potassium ions across the membrane to compensate for their constant leakage. In which direction is each ion pumped? a) K+ is pumped out of the cell and Na+ is pumped into the cell b) both Na+ and K+ are pumped into the cell c) Na+ is pumped out of the cell and K+ is pumped into the cell d) both Na+ and K+ are pumped out of the cell

Na+ is pumped out of the cell and K+ is pumped into the cell

The Na+-K+ pump actively transports both sodium and potassium ions across the membrane to compensate for their constant leakage. In which direction is each ion pumped?

Na+ is pumped out of the cell and K+ is pumped into the cell.

What prevents the Na+ and K+ gradients from dissipating? a) H+-K+ ATPase b) Na+-K+ ATPase c) Na+ and K+ leaks d) Na+ cotransporter

Na+-K+ ATPase

Which of the following membrane proteins is involved in active transport? a) Na+ leak channel b) Na+/K+ pump c) K+ leak channel d) Na+ voltage-gated channel

Na+/K+ pump

What is the role of neurotransmitter at a chemical synapse?

Neurotransmitter binds to receptors on the postsynaptic cell membrane and allows ions to diffuse across the membrane.

Dark-staining clusters of RER and ribosomes in neurons are called ________. a) dendrites b) neurofibrils c) Nissl bodies d) nodes of Ranvier

Nissl bodies

The rough ER of the cell.

Nissl bodies

An exceptionally strong stimulus can trigger a response.

Relative refractory period

The specific period during which potassium ions diffuse out of the neuron due to a change in membrane permeability.

Repolarization

Which of the following peripheral nervous system (PNS) neuroglia form the myelin sheaths around larger nerve fibers in the PNS?

Schwann cells

Define: neurolemmocytes

Schwann cells (also called neurolemmocytes) surround all nerve fibers in the PNS and form myelin sheaths around the larger fibers. Myelin protects and electrically insulates nerve fibers, and it increases the transmission speed of nerve impulses.

Numerous nerve impulses arriving at a synapse at closely timed intervals exert a cumulative effect.

Temporal summation

Numerous nerve impulses arriving at a synapse at closely timed intervals exert a cumulative effect. A) Spatial summation B) Subthreshold stimulus C) Threshold stimulus D) Temporal summation

Temporal summation

Which of the following best describes the Na+ and K+ concentrations across a neuron's plasma membrane?

The Na+ concentration is higher outside the cell compared to inside. The K+ concentration is higher inside the cell compared to outside.

Imagine that the cell membrane from the previous problem becomes more permeable to . Predict how this will affect the RMP.

The RMP will be more positive.

etraethylammonium (TEA) blocks voltage-gated K+ channels such that K+ cannot pass even when the channels are open. However, TEA leaves K+ leakage channels largely unaffected. How would you expect the action potential to change if you treated a neuron with TEA?

The action potential would depolarize as usual, but the repolarization phase would take longer, causing the action potential to be more broad in time.

Why does the action potential only move away from the cell body?

The areas that have had the action potential are refractory to a new action potential.

Which of the neuroglial cell types is the most abundant in the CNS?

The astrocytes within the CNS support neurons and anchor them to their nutrient source.

The cell body of the neuron is called

The cell body of neurons are alternatively termed perikaryon or soma.

What is the central nervous system

The central nervous system, which consists of the brain and spinal cord, is the integrating and control center of the nervous system. It interprets sensory input and dictates motor output based on reflexes, current conditions, and past experience.

Destruction of which of the neuroglial cell types leads to the disease multiple scleroses (MS)?

The defects in nerve transmission associated with MS are caused by a loss of myelin within the CNS. Myelin within the CNS is primarily produced by the oligodendrocytes

On average, the resting membrane potential is -70 mV. What does the sign and magnitude of this value tell you?

The inside surface of the plasma membrane is much more negatively charged than the outside surface.

What characterizes depolarization, the first phase of the action potential?

The membrane potential changes from a negative value to a positive value.

What event triggers the generation of an action potential?

The membrane potential must depolarize from the resting voltage of -70 mV to a threshold value of -55 mV.

What is the function of the myelin sheath?

The myelin sheath increases the speed of action potential conduction from the initial segment to the axon terminals.

The resting membrane potential depends on two factors that influence the magnitude and direction of Na+ and K+ diffusion across the plasma membrane. Identify these two factors.

The presence of concentration gradients and leak channels

During action potential propagation in an unmyelinated axon, why doesn't the action potential suddenly "double back" and start propagating in the opposite direction?

The previous axonal segment is in the refractory period.

In their resting state, all body cells exhibit a resting membrane potential ranging from -50 to about +50 millivolts.

The resting membrane potential is maintained by solely by passive transport processes.

Hypothetically, what would be the most immediate effect of doubling the number of Na+ leakage channels in the plasma membrane?

The resting membrane potential would become less negative (more positive).

Suppose a drug is developed that blocks K+ leakage channels. The drug prevents ions from passing through those channels. If this drug was applied to a neuron, what would be the most immediate effect on that neuron?

The resting membrane potential would become less negative (more positive).

Which of the neuroglial cell types are found in the PNS?

The satellite cell, wraps and insulates the soma of neurons within ganglia in the PNS.

Which of the following allows us to consciously control our skeletal muscles? a. the somatic nervous system b. the parasympathetic division of the autonomic nervous system c. the sympathetic division of the autonomic nervous system d. the afferent division of the nervous system

The somatic nervous system

The myelin on myelinated neurons can be degraded or destroyed in diseases such as multiple sclerosis-a process called demyelination. If a myelinated neuron was affected by demyelination, how would this affect action potentials in that neuron?

The speed of action potential propagation would be slower.

Select the correct statement regarding synapses.

The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another.

Select the correct statement regarding chemical synapses. A) The synaptic cleft uses the action potential to transmit a chemical signal to the post synaptic cell. B) The release of neurotransmitter molecules gives cells the property of being electrically coupled. C) Cells with gap junctions use chemical synapses. D) Neurotransmitter receptors are located on the axons terminals of cells.

The synaptic cleft uses the action potential to transmit a chemical signal to the post synaptic cell.

Describe Unipolar neuron

The unipolar neuron has a single short process that emerges from the cell body and divides into proximal and distal branches. Such neurons are found chiefly in the ganglia in the PNS where they conduct sensory information.

The plasma membrane is much more permeable to K+ than to Na+. Why?

There are many more K+ leak channels than Na+ leak channels in the plasma membrane.

Which of the following is NOT true of an electrical synapse?

They are specialized for release and reception of chemical neurotransmitters.

Which of the following is NOT a characteristic of peroxisomes?

They contain powerful enzymes called acid hydrolases.

Which of the following is not true of graded potentials?

They increase amplitude as they move away from the stimulus point.

Which of the following is not true of graded potentials? A) They increase amplitude as they move away from the stimulus point. B) They can be called postsynaptic potentials. C) They can form on receptor endings. D) They are short-lived.

They increase amplitude as they move away from the stimulus point.

The action potential is caused by permeability changes in the plasma membrane.

True

The oligodendrocytes can myelinate several axons.

True

The overlapping functions of the nervous system are sensory input, integration, and motor output.

True

True or False: Astrocytes are the most abundant and versatile glial cells

True

True or False: Motor, or efferent, neurons carry impulses away from the CNS to the effector organs (muscles and glands) of the body periphery.

True

True or False: dendrites are always nonmyelinated

True

True/False 10) The pacemaker of the heart under normal circumstances is called the sinoatrial (SA) node.

True

True/False 11) Systole means contraction of the ventricles.

True

True/False 14) Reductions in venous return cause reductions in both stroke volume and cardiac output.

True

True/False 16) Smooth muscle and elastic tissue in a blood vessel wall is found primarily in the tunica media.

True

True/False 18) Exchanges between blood and tissue cells occur in capillary beds

True

True/False 19) When precapillary sphincters are closed, blood flows through the shunts and bypasses the tissue cells.

True

True/False 2) The pulmonary arteries carry deoxygenated blood to the lungs

True

True/False 23) The common iliac vein drains blood into the inferior vena cava.

True

True/False 25) The great saphenous vein, the longest vein in the body, drains deoxygenated blood from the dorsal venous arch in the foot which then empties into the femoral vein.

True

True/False 28) The umbilical vein carries blood rich in nutrients and oxygen to the fetus.

True

True/False 31) An increase in blood vessel diameter causes arterial blood pressure to decrease

True

True/False 33) Cold temperatures have a vasoconstricting effect on blood vessels.

True

True/False 4) The tricuspid valve is located on the right side of the heart between the right atrium and right ventricle.

True

True/False 6) Arteries always carry blood away from the heart.

True

True/False 8) The coronary sulcus is also known as the atrioventricular groove.

True

True/False 9) The part of the intrinsic conduction system of the heart that directly supplies the walls of the ventricles is the Purkinje fibers.

True

Unipolar neurons have axons structurally divided into peripheral and central processes.

True

Voltage is always measured between two points and may be called the potential between these two points.

True

Which of these ions is actively transported through the cell membrane to establish a resting potential? A) Cl B) Ca C) Mg D) Na

D) Na

Receptive region of the neuron.

Dendrites

The interior of the cell becomes less negative due to an influx of sodium ions.

Depolarization

1) The thick layer of the heart wall that contains contractile cardiac muscle tissue is the: A) VISCERAL PERICARDIUM B) PARIETAL PERICARDIUM C) ENDOCARDIUM D) EPICARDIUM E) MYOCARDIUM

E

10) Which one of the following blood vessels carries oxygenated blood: A) superior vena cava B) inferior vena cava C) coronary sinus D) pulmonary artery E) pulmonary

E

14) Which one of the following represents the correct path for the transmission of an impulse in the intrinsic conduction system of the heart: A) atrioventricular (AV) node, sinoatrial (SA) node, atrioventricular (AV) bundle, right and left bundle branches, Purkinje fibers B) atrioventricular (AV) node, atrioventricular (AV) bundle, sinoatrial (SA) node, Purkinje fibers, right and left bundle branches C) sinoatrial (SA) node, atrioventricular (AV) bundle, atrioventricular (AV) node, Purkinje fibers, right and left bundle branches D) sinoatrial (SA) node, atrioventricular (AV) bundle, atrioventricular (AV) node, right and left bundle branches, Purkinje fibers E) sinoatrial (SA) node, atrioventricular (AV) node, atrioventricular (AV) bundle, right and left bundle branches, Purkinje fibers

E

21) The path of blood flow within the systemic vascular system is: A) arterioles, arteries, capillary beds, venules, veins B) arterioles, arteries, capillary beds, veins, venules C) arterioles, arteries, venules, veins, capillary beds D) arteries, arterioles, capillary beds, veins, venules E) arteries, arterioles, capillary beds, venules, veins

E

23) Which of the following reduces heart rate: A) exercise B) epinephrine C) thyroxine D) increased body temperature E) high blood pressure

E

24) Veins: A) carry blood away from the heart B) branch into smaller vessels called arterioles C) transport oxygen-rich blood D) operate under high pressure E) often have valves to prevent the backflow of blood

E

27) Which of the following blood vessels is a direct branch of the ascending aorta: A) right subclavian artery B) carotid artery C) right coronary artery D) left coronary artery E) both the right and left coronary arteries

E

34) The external iliac vein receives blood from all of the following EXCEPT: A) anterior tibial vein B) fibular vein C) popliteal vein D) femoral vein E) vertebral vein

E

Which of the neurological cell types shown are found in the peripheral nervous system (PNS)?

E

32. In a resting membrane the

ECF has a higher concentration of Na+ than the ICF

Which of the neuroglial cell types control the flow of cerebrospinal fluid within the CNS?

Ependymal cells line central cavities of the CNS. Much as the cilia of respiratory epithelium moves mucous along the surface of the tissue layer, the cilia of ependymal cells help circulate the cerebrospinal fluid that nourishes and cushions the brain and spinal cord.

Give examples of Astrocytes

Examples of their many functions include: anchoring neurons to capillaries, aiding in the exchanges between neurons and blood, guiding the migration of young neurons, and helping control the chemical environment around neurons.

27) Action potentials can be generated by virtually all cells of the body because all cells possess cell membranes.

False

A positive feedback cycle is the main force in the generation of graded potentials at receptor ends.

False

Neurons that are far away from the center of the neuron pool and that are not easily excited by an incoming stimulus are in the discharge zone.

False

Saltatory conduction occurs because of the presence of salt (NaCl) around the neuron.

False

Strong stimuli cause the amplitude of action potentials generated to increase.

False

The all-or-none phenomenon as applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place.

False

The autonomic nervous system is under voluntary control; whereas, the somatic nervous system is involuntary.

False

The nodes of Ranvier are found only on myelinated, peripheral neuron processes.

False

The sodium-potassium pump ejects two Na+ from the cell and then transports three K+ back into the cell in order to maintain the concentration gradients for sodium and potassium.

False

The two major classes of graded potentials are transmitter potentials and receptor potentials.

False

True or False: Unmyelinated fibers conduct impulses faster than myelinated fibers.

False

True/False 12) During ventricular diastole, the bicuspid and tricuspid valves are closed.

False

True/False 13) Cardiac output is calculated by multiplying the stroke volume times the systolic blood pressure.

False

True/False 15) An increased firing of the parasympathetic nervous system causes increased cardiac output.

False

True/False 17) The larger arteries contain valves to prevent the backflow of blood.

False

True/False 20) The portion of the aorta in the abdominopelvic cavity is known as the thoracic aorta.

False

True/False 22) The superior and inferior mesenteric arteries drain blood from the intestines

False

True/False 24) Veins draining the head and arms empty into the inferior vena cava.

False

True/False 26) The circle of Willis involves blood flow through the liver.

False

True/False 27) The major vessels involved in hepatic portal circulation are the inferior and superior mesenteric arteries, the splenic artery, and the left gastric artery.

False

True/False 30) Diastolic blood pressure is the pressure in the arteries at the peak of ventricular contraction

False

True/False 32) Hypotension is diastolic blood pressure below 100 mm Hg.

False

True/False 5) The semilunar valves prevent the backflow of blood into the atria when the ventricles are contracting.

False

True/False 7) The coronary sinus on the backside of the heart drains deoxygenated blood from the wall of the heart into the left atrium.

False

21) __________ are abnormal heart sounds that are fairly common in young children with healthy hearts because their heart walls are relatively thin and vibrate with rushing blood.

Heart murmurs

28. Olm's law is

I Current= Voltage/Resistance

What is the basic difference between simple diffusion and facilitated diffusion across a cell membrane?

In facilitated diffusion, molecules only move with the aid of a protein in the membrane.

Which of the following is a difference between primary and secondary active transport?

In primary active transport, the transport protein gets phosphorylated; in secondary active transport, the transport protein is not phosphorylated.

Which part of the neuron is responsible for generating a nerve impulse? Which part of the neuron is responsible for generating a nerve impulse? A. Chromatophilic substance B. Dendrite C. soma D. axon

Axon

11) The aortic semilunar valve is composed of: A) two cusps and opens when the left ventricle contracts B) three cusps and opens when the left ventricle contracts C) two cusps and opens when the right atrium contracts D) three cusps and opens when the right atrium contracts E) two cusps and closes when blood is filling the pulmonary circuit

B

13) The sinoatrial node is located in the: A) aorta B) right atrium C) left atrium D) right ventricle E) interventricular septum

B

15) A heart rate of over 100 beats per minute is called: A) bradycardia B) tachycardia C) ischemia D) diastole E) heart block

B

16) Which one of the following vessels receives blood during right ventricular systole: A) pulmonary veins B) pumonary trunk C) aorta D) superior vena cava E) coronary arteries

B

17) The mitral valve is normally closed: A) when the ventricle is in diastole B) when the ventricle is in systole C) when the atrium is contracting D) by the movement of blood from the atrium to the ventricle E) when the ventricle is contracting

B

29) Which of these arteries is NOT a branch of the abdominal aorta: A) renal arteries B) left common carotid artery C) inferior mesenteric artery D) common iliac arteries E) gonadal arteries

B

4) The right AV valve is known as the: A) aortic semilunar valve B) tricuspid valve C) mitral valve D) pulmonary semilunar valve E) bicuspid valve

B

7) When the ventricles contract, the bicuspid (mitral) valve prevents blood from flowing from the: A) right ventricle to the right atrium B) left ventricle to the left atrium C) left atrium to the right atrium D) right atrium to the left atrium E) left ventricle to the right ventricle

B

8) The tricuspid valve is located between the: A) right atrium and left atrium B) right atrium and right ventricle C) left ventricle and pulmonary artery D) left ventricle and aorta E) right ventricle and the pulmonary trunk

B

Which of the cell types shown helps determine capillary permeability?

B

18) A person with a heart rate of 75 beats per minute and a stroke volume of 60 mL per beat has a cardiac output of: A) 4500 mL/minute B) 1.25 mL/minute C) 0.8 mL/minute D) 6000 mL/minute E) 120 mL/minute

A

22) An increase in parasympathetic activity (primarily by the vagus nerves) causes: A) a decrease in both heart rate and cardiac output B) a decrease in heart rate and an increase in cardiac output C) an increase in both heart rate and cardiac output D) an increase in heart rate and a decrease in cardiac output E) no change in both heart rate and cardiac output

A

25) Which one of the following is caused by a decrease in venous return to the heart: A) a decrease in stroke volume and cardiac output B) a decrease in stroke volume and an increase in cardiac output C) an increase in stroke volume and cardiac output D) an increase in stroke volume and a decrease in cardiac output E) no change in stroke volume and cardiac output

A

32) Blood travels to the stomach by way of the branch of the celiac trunk called the: A) left gastric atery B) splenic artery C) common hepatic artery D) superior mesenteric artery E) inferior mesenteric artery

A

35) The brachial vein: A) drains blood from the radial and ulnar veins, then empties that blood into the axillary vein B) drains blood from the internal jugular vein, then empties that blood into the superior vena cava C) drains blood from the popliteal vein, then empties that blood into the external iliac vein D) drains blood from the axillary vein, then empties that blood into the superior vena cava E) drains blood from the popliteal vein, then empties that blood into the femoral vein

A

38) Which one of the following areas is NOT a pressure point: A) renal artery B) radial artery C) facial artery D) dorsalis pedis artery E) posterior tibial artery

A

6) What structure divides the left from the right ventricle: A) interventricular septum B) interatrial septum C) bicuspid valve D) tricuspid valve E) chordae tendineae

A

Destruction of which of the neuroglial cell types leads to the disease multiple sclerosis (MS)?

A

Which of neurological cell types shown form myelin sheaths within the CNS?

A

41. Nerve fibers fall into three groups: A, B, and C fibers

A fibers are the fastest

Which of the following is false or incorrect?

A nerve impulse occurs if the excitatory and inhibitory effects are equal.

Which of the following is false or incorrect? A) An excitatory postsynaptic potential occurs if the excitatory effect is greater than the inhibitory effect but less than threshold. B) An inhibitory postsynaptic potential occurs if the inhibitory effect is greater than the excitatory, causing hyperpolarization of the membrane. C) A nerve impulse occurs if the excitatory and inhibitory effects are equal.

A nerve impulse occurs if the excitatory and inhibitory effects are equal.

Which of the following is true of axons?

A neuron can have only one axon, but the axon may have occasional branches along its length.

described as multipolar neuron

A neuron that has many processes (axons and dendrites) that emerge from the cell body. Such a neuron is described as multipolar and typically functions as a motor neuron or interneuron.

Which of the following is a good example of a neuromodulator? A) acetylcholine B) nitric oxide C) any protein D) any carbohydrate

B) nitric oxide

89) Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?

A single type of channel will open, permitting simultaneous flow of sodium and potassium.

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane?

A single type of channel will open, permitting simultaneous flow of sodium and potassium.

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane? A) Sodium gates will open first, then close as potassium gates open. B) A single type of channel will open, permitting simultaneous flow of sodium and potassium. C) Specific sodium gates will open. D) Specific potassium gates will open.

A single type of channel will open, permitting simultaneous flow of sodium and potassium.

Neurons may be classified according to several characteristics. Which of the following is correct? A) Group C fibers are not capable of saltatory conduction. B) Group B fibers are highly myelinated and have the highest conduction velocities. C) Group A fibers are mostly somatic sensory and motor and are the smallest in diameter. D) A small cross-sectional area allows shorter conduction times.

A) Group C fibers are not capable of saltatory conduction.

Axon terminals release neurotransmitters. A) Secretory zone B) Conducting region C) Secretory region D) Trigger zone E) Receptive region

A) Secretory zone

Which of the following is not a function of the autonomic nervous system? A) innervation of skeletal muscle B) innervation of smooth muscle of the digestive tract C) innervation of cardiac muscle D) innervation of glands

A) innervation of skeletal muscle

Period during which the neuron cannot respond to a second stimulus, no matter how strong.

Absolute refractory period

The neuron cannot respond to a second stimulus, no matter how strong

Absolute refractory period

Also called a nerve impulse transmitted by axons.

Action potential

Adjacent Schwann cells along an axon and do not touch

Adjacent Schwann cells along an axon do not touch one another, so there are gaps in the sheath. These myelin sheath gaps, or nodes of Ranvier, occur at regular intervals (about 1 mm apart) along a myelinated axon. Axon collaterals can emerge from the axon at these gaps.

What conditions will increase the diffusion of molecules, such as neurotransmitters?

An increase in the amount of neurotransmitter exocytized by the presynaptic axon.

How is an action potential propagated along an axon?

An influx of sodium ions from the current action potential depolarizes the adjacent area.

2) The layer of the heart wall synonymous with the visceral layer of the serous pericardium is: A) myocardium B) endocardium C) epicardium D) parietal layer of the serous pericardium E) either endocardium or epicardium

C

20) The volume of blood pumped out by each ventricle with each beat of the heart is called the: A) cardiac output B) cardiac cycle C) stroke volume D) heart rate E) diastolic pressure

C

26) Which one is the correct sequence going from the outermost to the innermost layer of a blood vessel wall: A) tunica media, tunica intima, tunica externa B) tunica media, tunica externa, tunica intima C) tunica externa, tunica media, tunica intima D) tunica externa, tunica intima, tunica media E) tunica intima, tunica media, tunica externa

C

30) Which of these pathways correctly traces blood as it travels from the aortic arch to the left arm: A) aortic arch, brachiocephalic trunk, right common carotid artery B) aortic arch, left common carotid artery, left internal carotid artery C) aortic arch, left subclavian artery, left axillary artery, left brachial artery D) ascending aorta, right coronary arteries E) abdominal aorta, celiac trunk, left gastric artery

C

31) The carotid artery is located in the: A) armpit B) groin C) neck D) abdomen E) leg

C

33) The right and left renal veins empty blood from the: A) kidneys B) common iliac vein C) inferior vena cava D) hepatic portal vein E) vertebral vein

C

37) Which one of the following blood vessels in the fetus has the highest concentration of oxygen: A) umbilical arteries B) inferior vena cava C) ductus venosus D) ductus arteriosus E) left atrium

C

40) The friction blood encounters as it flows through the vessels is called: A) cardiac output B) stroke volume C) peripheral resistance D) blood pressure E) diastolic pressure

C

41) Generalized vasoconstriction occurs as a result of: A) an increase in parasympathetic nervous system firing B) a decrease in parasympathetic nervous system firing C) an increase in sympathetic nervous system firing D) a decrease in sympathetic nervous system firing E) an increase in blood pressure

C

44) Substances tend to leave the bloodstream at the arterial end of the capillary because: A) the osmotic pressure of the blood is higher at the arterial end of the capillary B) the osmotic pressure of the blood is higher at the venular end of the capillary C) blood pressure is higher at the arterial end of the capillary D) blood pressure is higher at the venular end of the capillary E) interstitial pressure is higher at the arterial end of the capillary

C

5) Pulmonary veins: A) transport oxygenated blood to the lungs B) transport blood rich in carbon dioxide to the lungs C) transport oxygenated blood to the heart D) split off the pulmonary trunk E) return blood to the right atrium of the heart

C

9) The superior vena cava empties: A) oxygenated blood into the left atrium B) oxygenated blood into the left ventricle C) deoxygenated blood into the right atrium D) deoxygenated blood into the right ventricle E) deoxygenated blood into the left atrium

C

In which area of the neuron is an action potential initially generated?

C

Which of the following membrane regions would have significant numbers of voltage-gated ion channels?

C and D

Which of the following is correct relative to Ohm's law? A) The more intense the stimulus, the more voltage changes. B) I = R / V C) Current is directly proportional to the voltage. D) R = V + I

C) Current is directly proportional to the voltage.

Select the correct statement about serial processing. A) Memories are triggered by serial processing. B) Smells are processed by serial pathways. C) Spinal reflexes are an example of serial processing. D) Input travels along several different pathways.

C) Spinal reflexes are an example of serial processing.

The part of a neuron that conducts impulses away from its cell body is called a(n) ______.

C) axon

The chemically gated channel, NMDA, allows ______ions entry into the nerve cell.

Ca2+

Which of these ions triggers exocytosis of synaptic vesicles? a) Ca2+ b) Na+ c) K+ d) Cl-

Ca2+

What is the role of calcium in synaptic activity?

Calcium influx into the synaptic terminal causes vesicle fusion.

Based on your knowledge of action potentials in neurons, what can you conclude about how they occur in cardiac muscle fibers?

Cardiac muscle fibers depolarize more quickly and spend more time depolarized than neurons do.

When a neurotransmitter like acetylcholine is acting in an excitatory manner which of the following is likely a result of the acetylcholine acting on the post synaptic cell? A) Chemically gated chloride channels will open. B) Chemically gated potassium channels will open. C) Chemically gated sodium channels will open. D) Chemically gated sodium channels will be closed.

Chemically gated sodium channels will open.

60. ____ is most responsible for hyper-polarization from inhibitory receptors channels opening

Cl-

Plasma membrane exhibits voltage-gated Na+ and K+ channels. A) Secretory zone B) Conducting region C) Secretory region D) Trigger zone E) Receptive region

Conducting region

12) Which one of the following are direct branches of the left coronary artery: A) circumflex and marginal arteries B) anterior and posterior interventricular arteries C) anterior interventricular and marginal arteries D) anterior interventricular and circumflex arteries E) posterior interventricular and marginal arteries

D

19) Which one of the following is true concerning the lub-dup sounds of the heart: A) the first sound is longer and louder and is caused by closure of the tricuspid valve; the second sound is shorter and sharper and is caused by closure of the mitral valve B) the first sound is shorter and sharper and is caused by closure of the tricuspid valve; the second sound is longer and louder and is caused by closure of the mitral valve C) they are caused by contraction of the ventricles, followed by contraction of the atria D) the first sound is longer and louder and is caused by closure of the AV valves; the second sound is shorter and sharper and is caused by closure of the semilunar valves E) the first sound is shorter and sharper and is caused by closure of the semilunar valves; the second sound is longer and louder and is caused by closure of the AV valves

D

28) Which one of the following does NOT receive blood directly from the aortic arch: A) brachiocephalic artery B) left subclavian artery C) left common carotid artery D) right common carotid artery E) thoracic aorta

D

3) Which area of the heart receives blood from the systemic veins: A) right ventricle B) left ventricle C) aorta D) right atrium E) left atrium

D

36) The umbilical vein carries: A) metabolic wastes and carbon dioxide from the fetus to the placenta B) metabolic wastes and carbon dioxide from the placenta to the fetus C) oxygen and nutrients from the fetus to the placenta D) oxygen and nutrients from the placenta to the fetus E) blood from the navel into the inferior vena cava

D

39) In which one of the following blood vessels is blood pressure the highest: A) veins B) capillaries C) vena cava D) arteries E) arterioles

D

42) Which one of the following is the main function of renin and aldosterone: A) they are produced whenever blood pressure rises and ultimately cause an increase in blood volume and blood pressure B) they are produced whenever blood pressure rises and ultimately cause a decrease in blood volume and blood pressure C) they are produced when blood pressure rises and have no long-term effect on blood volume and blood pressure D) they are produced whenever blood pressure falls and ultimately cause an increase in blood volume and blood pressure E) they are produced whenever blood pressure falls and ultimately cause a decrease in blood volume and blood pressure

D

43) Which one of the following are the main functions of renin and angiotensin II: A) blood pressure rises this causes vasoconstriction and further increases blood pressure B) blood pressure rises this causes vasoconstriction and a decrease in blood pressure C) blood pressure rises this causes vasodilation and a decrease in blood pressure D) blood pressure falls this causes vasoconstriction and an increase in blood pressure E) blood pressure falls this causes vasodilation and an increase in blood pressure

D

45) Varicose veins are caused by: A) a loss of elasticity in blood vessels B) the accumulation of fatty substances within blood vessels C) excessive production of the enzyme renin D) incompetent venous valves E) orthostatic hypotension

D

Which of the cell types shown is most associated with the production and flow of the cerebrospinal fluid (CSF)?

D

What changes occur to voltage-gated Na+ and K+ channels at the peak of depolarization?

Inactivation gates of voltage-gated Na+ channels close, while activation gates of voltage-gated K+ channels open.

During the hyperpolarization phase of the action potential, when the membrane potential is more negative than the resting membrane potential, what happens to voltage-gated ion channels?

K+ channels close. Na+ channels go from an inactivated state to a closed state.

During an action potential, hyperpolarization is caused by: a) K+ influx b) Na+ efflux c) K+ efflux d) Na+ influx

K+ efflux

Which of the following is the clearest example of a neuronal membrane's selective permeability?

K+ ions can diffuse across the membrane more easily than Na+ ions.

During an action potential, hyperpolarization beyond (more negative to) the resting membrane potential is primarily due to __________.

K+ ions diffusing through voltage-gated channels

The repolarization phase of the action potential, where voltage becomes more negative after the +30mV peak, is caused primarily by __________.

K+ ions leaving the cell through voltage-gated channels

Which of the following causes the hyperpolarization phase of an action potential? a) K+ outflow via voltage-gated potassium ion channels b) Na+ outflow via voltage-gated sodium ion channels c) K+ influx via voltage-gated potassium ion channels d) Na+ influx via voltage-gated sodium ion channels

K+ outflow via voltage-gated potassium ion channels

The membranes of neurons at rest are very permeable to __________ but only slightly permeable to ___________. a) K+; Cl- b) K+; Na+ c) Na+; Cl- d) Na+; K+

K+; Na+

Sodium and potassium ions can diffuse across the plasma membranes of all cells because of the presence of what type of channel?

Leak channels

Which statement best describes exocytosis?

Membrane organelles fuse with the membrane and release contents out of the cell.

Which of the following is NOT true of association neurons?

Most association neurons are confined within the peripheral nervous system (PNS).

What type of channel on the postsynaptic membrane binds neurotransmitter?

a chemically gated channel

27. A substance with low electrical resistance is called

a conductor

The neural circuit pattern in which the signal goes from several neurons to one is called _______________. a) a diverging circuit b) a stabilizing circuit c) an amplifying circuit d) a converging circuit

a converging circuit

The part of the neuron that normally receives stimuli is called ____.

a dendrite

35. A -30 mV membrane potential would be an example of

a depolarized membrane

36. The following is least likely to produce an action potential

a hyper-polarized membrane

A bundle of axons in the PNS is called _______. a) a tract b) a spinal cord c) a ganglion d) a nerve

a nerve

A postsynaptic cell can be a neuron, a muscle cell, or a secretory cell. What is an example of a presynaptic cell?

a neuron

which of the following is true of axons?

a neuron can have only one axon, but the axon may have occasional branches along its length

If a post synaptic cell is stimulated to threshold by temporal summation this implies that ________. A) the postsynaptic cell can be influenced by only one presynaptic cell B) the postsynaptic cell is sending frequent action potential C) a presynaptic neuron is sending frequent EPSP D) the presynaptic neuron is sending frequent IPSP

a presynaptic neuron is sending frequent EPSP

The velocity of the action potential is fastest in which of the following axons? a) a large unmyelinated axon b) a small unmeylinated axon c) a small myelinated axon

a small myelinated axon

42. The functional connection between neurons is called

a synapse

What is a membrane potential?

a voltage or electrical charge across the plasma membrane

If a neuron had a mutation that prevented the production of voltage-gated Na+ channels, what function would the neuron NOT be able to accomplish? a. depolarization leading to action potentials b. graded depolarization c. graded hyperpolarization d. resting membrane potentials

a. depolarization leading to action potentials

Which of the choices below describes the ANS? a. motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands b. sensory and motor neurons that supply the digestive tract c. motor fibers that conduct nerve impulses from the CNS to skeletal muscles

a. motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands

Cranial nerve II, the optic nerve sends nerve impulses to the brain carrying information about the things we see. These nerve fibers most likely belong to which division of the nervous system? a. sensory (afferent) division b. somatic nervous system c. sympathetic division d. parasympathetic division

a. sensory (afferent) division

Which of these materials or structures would be found in greatest amounts or numbers at E? a. vesicles containing neurotransmitter b. chemically gated sodium ion channels c. chromatophilic substance (Nissl bodies) d. the nucleolus

a. vesicles containing neurotransmitter

An excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle is ________.

acetylcholine

The first identified neurotransmitter was

acetylcholine

The mechanism by which the neurotransmitter is returned to a presynaptic neuron's axon terminal is specific for each neurotransmitter. Which of the following neurotransmitters is broken down by an enzyme beofre being returned? a) acetylcholine b) glutamate

acetylcholine

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle?

acetylcholine

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle? A) gamma aminobutyric acid B) cholinesterase C) norepinephrine D) acetylcholine

acetylcholine

Which of the following correctly describes a graded potential?

amplitude of various sizes

Which statement best describes the all-or-none principle? a) all neurons conduct an action potential together, or none do b) all voltage-gated sodium channels will open or none will open c) an action potential happens completely, or it doesn't happen at all d) local, or graded, potentials will always become action potentials

an action potential happens completely, or it doesn't happen at all

How is an action potential propagated along in an axon? a) an influx of sodium ions from the current action potential depolarizes the adjacent area b) stimuli from the graded (local) potentials from the soma and dendrites depolarize the entire axon c) an efflux of potassium from the current action potential depolarizes the adjacent area

an influx of sodium ions from the current action potential depolarizes the adjacent area

Which of the following describes the nervous system integrative function? A) responds to stimuli by gland secretion or muscle contraction B) analyzes sensory information, stores information, makes decisions C) senses changes in the environment

analyzes sensory information, stores information, makes decisions

Which of the following describes the nervous system integrative function? A. responds to stimuli by gland secretion or muscle contraction B. analyzes sensory information, stores information, makes decisions C. senses changes in the environment

analyzes sensory information, stores information, makes decisions

8) Crushing chest pain caused by oxygen deprivation of the myocardium is called __________.

angina pectoris

21. Movement away from the cell body is called

anterograde

Cold sores on the skin of the mouth occur when herpes simplex viruses that are dormant in neural ganglia become active and travel to the skin of the mouth. Which of the following is the mechanism by which these viruses travel from the ganglia (located within the head) to the skin of the mouth?

anterograde transport

12) The pointed tip of the heart that is directed toward the left hip is called the __________.

apex

Nerve cell adhesion molecules (N-CAMs) ________.

are crucial for the development of neural connections

Define: Microglial cells

are small andovoid with relatively long "thorny" processes. Their processes touch nearby neurons, monitoring their health, and when they sense that certain neurons are injured or are in other trouble, the microglial cells migrate toward them. Where invading microorganisms or dead neurons are present, the microglial cells transform into a special type of macrophage that phagocytizes the microorganisms or neuronal debris.

29) Larger blood vessels that carry blood away from the heart are called __________.

arteries

A neuron that has as its primary function the job of connecting other neurons is called a(n) _____.

association neuron

A neuron that has as its primary function the job of connecting other neurons is called a(n) ________.

association neuron

14. The most abundant neuroglia of the CNS is

astrocytes

Neuroglia that control the chemical environment around neurons by buffering potassium and recapturing neurotransmitters are ________.

astrocytes

Which neuroglia are the most abundant and versatile of the glial cells? A. ependymal cells B. astrocytes C. Schwann cells D. oligodendrocytes

astrocytes

15. What two cells are best pair functionally

astrocytes and satellite cells

During what part of the action potential do voltage-gated Na+ channels begin to inactivate (their inactivation gates close)?

at the end of the depolarization phase, as the membrane potential approaches its peak value

Where are action potentials regenerated as they propagate along a myelinated axon?

at the nodes of Ranvier

10) The two superior receiving chambers of the heart are known as the __________, while the two inferior discharging chambers of the heart are known as the __________.

atria; ventricles

11) The valves located between the atria and ventricles are known as the __________ valves.

atrioventricular (or AV)

Involuntary control of smooth and cardiac muscles and glands is provided by the __________. a) visceral sensory division b) afferent division c) autonomic nervous system d) somatic motor division

autonomic nervous system

The part of a neuron that conducts impulses away from its cell body is called a(n) ________.

axon

Which of the following is the conducting region of the neuron?

axon

which of the following is the conducting region of the neuron?

axon

18. The cone shaped area that leads into the process leaving the cell body is called the

axon hillock

Where in the neuron is an action potential initially generated? a) axon hillock b) soma and dendrites c) anywhere on the axon

axon hillock

20. The distal end of an axon is called

axon terminals and terminal boutons

40. When talking of conduction velocities of a nerve a(n)

axon with saltatory conduction is faster than continuous

Bacteria in the blood stream can be prevented entry to the fluids surrounding the brain. Which cells are most responsible for preventing bacterial from entering the fluids of the brain? a. satellite cells b. astrocytes c. Schwann cells d. oligodendrocytes

b. astrocytes

Collections of nerve cell bodies in the peripheral nervous system are called ________. a. nuclei b. ganglia c. nerves d. tracts

b. ganglia

Like all cells, the neurons' internal organization dictates its function. Neurons have relatively many mitochondria, an extensive network of rough endoplasmic reticulum and many clusters of ribosomes. These cellular features indicated all of the following EXCEPT _________. a. neurons must meet a high demand for ATP b. neurons have stable, relatively unchanging internal environments c. neurons produce many proteins d. neurons have a relatively high consumption of oxygen

b. neurons have stable, relatively unchanging internal environments

Which of the following circuit types is involved in the control of rhythmic activities such as the sleep-wake cycle, breathing, and certain motor activities (such as arm swinging when walking)? a. parallel after-discharge circuits b. reverberating circuits c. converging circuits d. diverging circuits

b. reverberating circuits

Which is the main receptive portion of the neuron? a. the synapse b. the dendrite c. the axon d. the cell body or soma

b. the dendrite

Select the correct statement regarding chemical synapses. a. Neurotransmitter receptors are located on the axons terminals of cells. b. The synaptic cleft transmits a chemical signal to the post synaptic cell through diffusion of neurotransmitters across the cleft. c. Cells with gap junctions use chemical synapses. d. The release of neurotransmitter molecules gives cells the property of being electrically coupled.

b. the synaptic cleft transmits a chemical signal to the post synaptic cell through diffusion of neurotransmitters across the cleft.

43) The pressure blood exerts against the inner walls of the blood vessels is known as __________.

blood pressure

47) Fluid tends to be forced out of a capillary bed by __________ while __________ tends to draw fluid into the capillary bed.

blood pressure; osmotic pressure

Which areas of this neuron would be classified as receptive regions?

both A and B

during depolarization, which gradient moves Na+ into the cell?

both chemical and electrical

44. Most neurons function as

both pre and post synaptic neurons

During depolarization, which gradient(s) move(s) Na+ into the cell? a) both the electrical and chemical gradients b) only the chemical gradient c) only the electrical gradient d) Na+ does not move into the cell. Na+ moves out of the cell

both the electrical and chemical gradients

38) The __________ veins join to form the superior vena cava before emptying into the right atrium.

brachiocephalic

The term central nervous system refers to the _______.

brain and spinal cord

The term central nervous system refers to the ________.

brain and spinal cord

The term central nervous system refers to the ________. A) brain and spinal cord B) sensory (afferent) nerves C) the somatic nerves D) the spinal nerves

brain and spinal cord

Which of the following are organs of the central nervous system? a) brain and cranial nerves b) spinal cord and spinal nerves c) brain and spinal cord d) brain, cranial nerves, spinal cord, and spinal nerves

brain and spinal cord

A neuromodulator is a chemical messenger released by neurons that does not cause EPSPs or IPSPs

but does affect the strength of synaptic transmission

How do neurofibrils differ from nerve fibers? a. There is no real difference, since they are both capable of impulse conduction away from a neuron. b. Neurofibrils are axon subunits that are bundled together to make up a single nerve fiber. c. Neurofibrils are cytoskeletal intermediate filaments maintaining cell shape, but they do not conduct impulses.

c. Neurofibrils are cytoskeletal intermediate filaments maintaining cell shape, but they do not conduct impulses.

Which of the following peripheral nervous system (PNS) neuroglia from the myelin sheaths around larger nerve fibers in the PNS? a. oligodendrocytes b. satellite cells c. Schwann cells d. astrocytes

c. Schwann cells

Many neurons have many short, branching extensions called dendrites. What is the benefit of these structures for a neuron? a. There is a large amount of space for myelin to form and make electrical conduction more efficient. b. There is a large area for production of chemicals used to signal other neurons c. The dendrites provide a large surface are for connections from other neurons. d. There is a large surface area to send signals to other cells

c. The dendrites provide a large surface area for connections from other neurons.

Which of the following is NOT a difference between graded action potentials and action potentials? a. Graded potentials occur along dendrites, whereas action potentials occur along axons. b. Greater stimulus intensity results in larger graded potentials, but not larger action potentials. c. The magnitude of action potentials decrease as the impulse travels further away from the start of the impulse while graded potentials do not decrease in magnitude.

c. The magnitude of action potentials decrease as the impulse travels further away from the start of the impulse while graded potentials do not decrease in magnitude.

Suppose that both stimuli seen in these graphs happened equally at the same time on a postsynaptic membrane as a result of two different synapses. Which of the following best descries the result? a. Temporal summation would occur. b. No chemically gated ion channels would open. c. There would be little or no graded potential. d. An action potential would result.

c. There would be little or no graded potential.

Ependymal cells line many open cavities in the central nervous system (CNS). Ependymal cells have cilla on the side of the cell that face these openings. What is the most likely function of these ciliated cells? a. exchange of nutrients between the circulatory system and neurons b. act as macrophage cells to destroy microorganisms or neuronal debris c. movement and circulation of cerebrospinal fluid d. create myelin sheaths for CNS cells

c. movement and circulation of cerebrospinal fluid

Which of the following stimuli caused the reaction in the graph on the left? a. opening of gated Ca2+ channels b. opening of gated K+ channels c. opening of gated Na+ channels d. opening of gated Cl- channels

c. opening of gated Na+ channels

Which of the following is NOT a function of astrocytes? a. anchor neurons to blood vessels. b. support and brace neurons. c. provide the defense for the CNS. d. control the chemical around neurons.

c. provide the defense for the CNS.

30) The smallest blood vessels known as __________ connect arterioles and venules.

capillaries

32) The amount of blood being pumped out of the heart at any time is called __________.

cardiac output

Bundles of axons known as tracts are part of the: a) ganglion b) myelin sheath c) central nervous system d) peripheral nervous system

central nervous system

What part of the nervous system performs information processing and integration?

central nervous system

Which nervous system division is responsible for the integration of sensory information? a) visceral motor division b) peripheral nervous system c) somatic motor division d) central nervous system

central nervous system

The two anatomical divisions of the nervous system are the: a) sensory division and motor division b) somatic sensory division and visceral sensory system c) central nervous system and peripheral nervous system d) visceral motor division and somatic motor division

central nervous system and peripheral nervous system

45. Two main types of synapses are

chemical and electrical

The presence of a synaptic cleft between cells is characteristic of: a) electrical synapse b) chemical synapse c) both chemical and electrical synapses d) neither chemical nor electrical synapses

chemical synapse

Which component has a role in the postsynaptic cell during synaptic activity?

chemically gated channels

Binding of a neurotransmitter to its receptors opens ___________ channels on the ____________ membrane. a) chemically gated; presynaptic b) voltage-gated; postsynaptic c) voltage-gated; presynaptic d) chemically gated; postsynaptic

chemically gated; postsynaptic

Which of the following is NOT one of the chemical classes into which neurotransmitters fall?

chlorides

14) The tiny white cords that anchor the cusps or flaps of endocardium to the walls of the ventricles are called the __________.

chordae tendineae

40) The complete circle of connecting vessels in the brain is called the __________.

circle of Willis or cerebral arterial circle

Ependymal cells: a) form myelin in the brain and spinal cord b) help form the blood-brain barrier c) serve as wandering phagocytes during brain injury d) circulate cerebrospinal fluid

circulate cerebrospinal fluid

Branches that may occur along an axon are called: a) collaterals b) dendrites c) hillocks d) telodendria

collaterals

4. What is false of the central nervous system

consist of nerves that extend from the brain/spinal cord

Action potential propagation in unmyelinated axons happens via: a) saltatory conduction b) synaptic transmission c) local potentials d) continuous conduction

continuous conduction

What type of conduction takes place in unmyelinated axons? a) saltatory conduction b) continuous conduction c) synaptic transmission d) electrical conduction

continuous conduction

18) When ventricles __________, the AV valves are closed.

contract

19) The coronary veins empty blood from the myocardium into a large vein on the posterior side of the heart known as the __________.

coronary sinus

1. The gray covering of the Cerebrum is called the

cortex

Which of the following is NOT one of the basic functions of the nervous system? a. integrate sensory input for decision making. b. Generate direct, electrical signals. c. Decode sensory information from the environment. d. Release hormones into the bloodstream to communicate with other cells in the body.

d. Release hormones into the bloodstream to communicate with other cells in the body.

Which of the following is an excitatory neurotransmitter secreted by motor neurons innervating skeletal muscle? a. cholinestrase b. norepinephrine c. gamma aminobutyric acid d. acetylcholine

d. acetylcholine

Bipolar neurons are commonly ________. a. found in ganglia b. called neuroglial cells c. motor neurons d. found in the retina of the eye

d. found in the retina of the eye

Nerve impulses are sent to slow the heart's rate of contraction. The nerve fibers sending these signals will most likely belong to which division of the nervous system? a. sensory (afferent) division b. somatic nervous system c. sympathetic division d. parasympathetic division

d. parasympathetic division

Which of the following is NOT a type of circuit? a. converging circuits b. diverging circuits c. reverberating circuits d. pre-synaptic circuits

d. pre-synaptic circuits

Which of the following statements most accurately describes the effects caused by binding of the neurotransmitter (green dots) to the structure labeled C? a. an action potential is generated b. the neurotransmitter is transported into the postsynaptic neuron c. the membrane potential of the presynaptic membrane changes d. the membrane potential of the postsynaptic membrane changes

d. the membrane potential of the postsynaptic membrane changes.

Which of the following is not characteristic of neurons? a. they have an exceptionlly high metabolic rate. b. they conduct impulses. c. the have extreme longevity. d. they are mitotic.

d. they are mitotic

Immediately after an action potential has peaked, which of the following channels will open? a. voltage gated calcium channels b. chemically gated chloride channels c. voltage gated sodium channels d. voltage gated potassium channels

d. voltage gated potassium channels

Which of the following is one of the mechanisms for termination of synaptic transmission? a) storage of neurotransmitter in vesicles b) reuptake of neurotransmitter into the postsynaptic cell c) release of neurotransmitter into the synaptic cleft d) degradation of neurotransmitter by enzyme

degradation of neurotransmitter by enzyme

Which of the following is a factor that determines the rate of impulse propagation, or conduction velocity, along an axon?

degree of myelination of the axon

Determine the direction in which and electrical signal is carried in a typical multipolar neuron. a) dendrites, cell body, axon b) cell body, axon, dendrites c) dendrites, axon, cell body d) axon, cell body, dendrites

dendrites, cell body, axon

An excitatory postsynaptic potential is a local ______________ of the postsynaptic membrane

depolarization

If a stimulus opens ligand-gated sodium ion channels, the neuron will ___________. a) remain at its resting membrane potential b) repolarize c) hyperpolarize d) depolarize

depolarize

An action potential is self-regenerating because _________. a) repolarizing currents established by the efflux of Na+ flow down the axon and trigger and action potential at the next segment b) repolarizing currents established by the efflux of K+ flow down the axon and trigger and action potential at eh next segment c) depolarizing currents established by the influx of K+ flow down the axon and trigger an action potential at the next segment d) depolarizing currents established by the influx of Na+ flow down the axon and trigger and action potential at the next segment

depolarizing currents established by the influx of Na+ flow down the axon and trigger an action potential at the next segment

an action potential is self-regenerating because...

depolarizing currents established by the influx of Na+‎ flow down the axon and trigger an action potential at the next segment

What is the role of acetylcholinesterase?

destroy ACh a brief period after its release by the axon endings

The role of acetylcholinesterase is to ________.

destroy ACh a brief period after its release by the axonal endings

Depolarization to threshold during action potential propagation in axons is due to: a) diffusion of K ions up to the previous segment of the axon b) diffusion of K ions down to the next segment of the axon c) diffusion of Na ions up to the previous segment of the axon d) diffusion of Na ions down to the next segment of the axon

diffusion of Na ions down to the next segment of the axon

The following are types of circuits in neuronal pools

diverging, converging, and reverberating

During the action potential, when does sodium permeability initially decrease? a) during repolarization b) during the peak of depolarization c) during hyperpolarization d) during the rising phase of depolarization

during the peak of depolarization

Bidirectional, instantaneous synaptic transmission is typical of ___________. a) electrochemical synapses b) chemical synapses c) electrical synapses d) all synapses

electrical synapses

Which of the following neurotransmitters inhibits pain and is mimicked by morphine, heroin, and methadone?

endorphin

Which neurotransmitter(s) is/are the body's natural pain killer?

endorphins

25. Which of the following statements is false

energy is bound when charges move towards one another

Caveolae are closely associated with all of the following except ________.

enzymes involved in cell metabolism

What are ciliated CNS neuroglia that play an active role in moving the cerebrospinal fluid called?

ependymal cells

9) The visceral layer of the serous pericardium is actually the same layer as the __________.

epicardium

Which membrane potential occurs because of the influx of Na+ through chemically gated channels in the receptive region of a neuron?

excitatory postsynaptic potential

A vesicle fuses with the plasma membrane and releases its contents to the extracellular fluid. This statement describes _____.

exocytosis

Neurotransmitter is released from presynaptic neurons through what mechanism?

exocytosis

Some transport processes use transport proteins in the plasma membrane, but do not require ATP. This type of transport is known as _____.

facilitated diffusion

The majority of water molecules moving across plasma membranes by osmosis do so via a process that is most similar to ____.

facilitated diffusion

The all-or- none phenomenon as applied to nerve conduction states that the whole nerve cell must be stimulated for conduction to take place.

false

The sensory, or afferent, division of he peripheral nervous system carries information from the brain and spinal cord to effector organs. a) true b) false

false

True/False 1) Cardiac muscle is enclosed by a double sac of serous membrane known as the peritoneum.

false

True/False 3) The chordae tendineae anchor the semilunar valves to the walls of the ventricles.

false

36) The blood vessel that is the immediate inferior continuation of the external iliac artery is the __________.

femoral artery

42) The flaplike opening in the interatrial septum of the fetus through which blood is shunted directly from the right atrium to the left atrium is the __________.

foramen ovale

Bipolar neurons are commonly ________.

found in the retina of the eye

What does the central nervous system use to determine the strength of a stimulus? A) size of action potentials B) origin of the stimulus C) type of stimulus receptor D) frequency of action potentials

frequency of action potentials

Loss of K ions from the cytosol will have the same effect as: a) gain of Na ions b) gain of Cl ions c) gain of K ions d) loss of Cl ions

gain of Cl ions

Collections of nerve cell bodies outside the central nervous system are called _______.

ganglia

Collections of nerve cell bodies outside the central nervous system are called ________.

ganglia

Collections of nerve cell bodies outside the central nervous system are called ________. A) ganglia B) nerves C) tracts D) nuclei

ganglia

When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________.

generator potential

When a sensory neuron is excited by some form of energy, the resulting graded potential is called a(n) ________. A) action potential B) excitatory potential C) postsynaptic potential D) generator potential

generator potential

34. Change in the resting membrane potential produce 2 types of potential signals: graded or action

graded potential travel short distances

Which group of fibers spreads impulses at up to 1 meter per second?

group C fibers

27) Cardiac output is the product of __________ and __________.

heart rate (HR); stroke volume (SR)

Ependymal cells ________.

help to circulate the cerebrospinal fluid.

39) The single vessel that drains blood from the digestive tract organs to the liver is the __________.

hepatic portal vein

An inhibitory postsynaptic potential (IPSP) is associated with ________.

hyperpolarization

An inhibitory postsynaptic potential (IPSP) is associated with ________. A) lowering the threshold for an action potential to occur B) a change in sodium ion permeability C) hyperpolarization D) opening of voltage-regulated channels

hyperpolarization

The relative refractory period is caused by: a) inactivation of voltage-gated Na ion channels b) depolarization to threshold c) hyperpolarization d) inactivation of voltage-gated K ion channels

hyperpolarization

A series of measurements with a voltmeter show a neuron's membrane potential becoming more negative, from -70 mV to -85 mV. This neuron is experiencing a: a) hyperpolarization phase b) polarization phase c) repolarization phase d) depolarization phase

hyperpolarization phase

In an inhibitory synapse the membrane of the postsynaptic neuron becomes

hyperpolarized

46) A systolic blood pressure reading below 100 mm HG is called __________.

hypotension

Batrachotoxin produced by certain species of frogs is a toxin that permanently opens voltage-gated Na ion channels. The results of exposure to batrachotoxin will be: a) inability to generate action potentinals b) increased frequency of action potentials c) no depolarization d) permanent hyperpolarization

inability to generate an action potential

what changes occur to voltage gated Na+ and K+ channels at the peak of depolarization?

inactivation gates of voltage gated Na+ channels close, while activation gates of voltage gated K+ channels open

Define: Multipolar

is a structural classification that groups neurons according to the number of processes extending from their cell body. Multipolar neurons have three or more processes - one axon and multiple dendrites.

Define: axon

is the conducting region of the neuron. It generates nerve impulses (action potentials) and transmits them, typically away from the cell body, along the axolemma (cell membrane of the axon).

3. Processing and interpretation of sensory input

is the function of the integration component

11. The counterpart in the central nervous system to schwann cells in the peripheral nervous system

is the oligodendrocytes

13) Lack of adequate blood supply to the heart is called __________.

ischemia

Which of the following correctly describes a graded potential? A) it has a depolarization, repolarization and hyperpolarization phase B) it can have amplitudes of various sizes C) it is initiated by voltage changes in the membrane D) it travels long distances

it can have amplitudes of various sizes

Conduction speed will be fastest in a ____________. a) large unmyelinated axon b) small unmyelinated axon c) small myelinated axon d) large myelinated axon

large myelinated axon

Sodium and potassium ions can diffuse across the plasma membranes of all cells because of the plasma membranes of all cells because of the presence of what type of channel? a) ligand-gated channels b) leak channels c) sodium-potassium ATPases d) voltage-gated channels

leak channels

31. The two types of ion channels in the membrane are

leakage and gated channels

24. What is true of interneurons

lie between motor and sensory neurons

Postsynaptic potentials are: a) local potentials b) action potentials c) resting potentials d) chemical potentials

local potentials

25) During diastole, the pressure in the heart is __________.

low

What is the major role of the Na+-K+ pump in maintaining the resting membrane potential?

maintaining the concentration gradients for Na+ and K+ across the cell membrane

What channels open or close in response to physical distortion of the membrane surface, such as vibrations or pressure? a) voltage-gated b) mechanically-gated c) chemically-gated d) ligand-gated

mechanically-gated

34) The flow of blood through a capillary bed is called __________.

microcirculation

Which of the following types of glial cells monitors the health of neurons, and can transform into a special type of macrophage to protect endangered neurons?

microglia

17) The bicuspid valve is also referred to as the __________ valve.

mitral

A primary active transport process is one in which __________.

molecules move through transport proteins that have been activated by ATP

22. Which is not a structural classification of neurons

monopolar

Which of the following would increase the membrane permeability to K+?

more K+ leakage channels

If the cytosol loses K+ ions through leak channels, it will become: a) less negative b) more positive c) more negative d) there will be no change in the membrane potential

more negative

Which of the choices below describes the ANS?

motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands

What symptoms would a nurse focus on in his or her care of a client with multiple sclerosis?

Visual disturbances, paralysis, and weakness

During the hyperpolarization phase of the action potential, voltage eventually returns to the resting membrane potential. What processes are primarily responsible for this return to the resting membrane potential?

Voltage-gated K+ channels close. K+ and Na+ diffuse through leakage channels.

What opens first in response to a threshold stimulus?

Voltage-gated Na+ channels

What is the first change to occur in response to a threshold stimulus?

Voltage-gated Na+ channels change shape, and their activation gates open.

29. Which opens and closes in response to changes in membrane potential

Voltage-gated channels

Which of the following best explains diffusion?

movement of molecules from an area of high concentration to an area of low concentration

Complete the following sentence. The operation of the ATPase pump __________.

moves 3 to the ECF and 2 to the cytoplasm

Which of the following is NOT a functional classification of neurons?

multipolar

In which type of axon will velocity of action potential conduction be the fastest? a) myelinated axons with the largest diameter b) unmyelinated axons of the shortest length c) unmyelinated axons with the largest diameter d) myelinated axons with the smallest diameters

myelinated axons with the largest diameter

Saltatory propagation occurs in _________ axons, in which action potentials __________. a) myelinated; move from one node of Ranvier to another b) unmyelinated; spread by depolarizing the adjacent region of the axon membran c) unmyelinated; move from one node of Ranvier to another d) myelinated; move continuously along the axon toward the axon hillock

myelinated; move from one node of Ranvier to another

Which of the following is an effect of myelination? a) myelination increases the speed of conduction of action potentials b) myelination increases the volume of cerebrospinal fluid in circulation c) myelination increases the rate of mitosis in damaged neurons d) myelination increases the rate at which phagocytosis occurs in the brain

myelination increases the speed of conduction of action potentials

6) The layer of the heart wall that receives the stimulus from letter E is called the __________.

myocardium

The interior surface of a neuron's plasma membrane at resting membrane potential will have a ________. A) negative charge and contains more sodium than outside of the cell B) positive charge and contains less sodium than outside of the cell C) positive charge and contains more sodium than outside of the cell D) negative charge and contains less sodium than outside of the cell

negative charge and contains less sodium than outside of the cell

In what way does the interior surface of a cell membrane of a resting (nonconducting) neuron differ from the external environment? The interior is ________.

negatively charged and contains less sodium

The sheath of Schwann is also called the ________.

neurilemma

19. The neuron cell membrane is called the

neurilemma and axolemma

Which of the following are bundles of neurofilaments that are important in maintaining the shape and integrity of neurons?

neurofibrils

16. Which is not a term for the excitable cell bodies of the nervous system

neuroglia

9. Nervous system histology reveal the following as glial cells except

neurons

The discharge zone refers to

neurons closer to the incoming fiber

Like all cells, the neurons' internal organization dictates its function. Neurons have relatively many mitochondria, an extensive network of rough endoplasmic reticulum and many clusters of ribosomes. These cellular features indicate all of the following EXCEPT ________. A) neurons produce many proteins B) neurons must meet a high demand for ATP C) neurons have a relatively high consumption of oxygen D) neurons have stable, relatively unchanging internal environments

neurons have stable, relatively unchanging internal environments

A molecule that carries information across a synaptic cleft is a: a) receiving neuron b) synapse c) synaptic cleft d) neurotransmitter e) sending neuron

neurotransmitter

The substance released at axon terminals to propagate a nervous impulse is called a(n) _______.

neurotransmitter

The substance released at axon terminals to propagate a nervous impulse is called a(n) ________.

neurotransmitter

If a neuron simultaneously receives a stimulus that results in local depolarization of 10 mV and a stimulus that results in a local hyperpolarization of 10 mV, the net effect would be: a) net depolarization b) no net change in membrane potential c) neurons can only receive one incoming stimulus at a time d) net hyperpolarization

no net change in membrane potential

Which of the following are gaps found along a myelin sheath?

nodes of Ranvier

13. Non-myelinated segments along periferal nerve are called

nodes of ranvier

7. The counterpart in the central nervous system for the ganglia is the

nuclei

Which of the following is not a chemical class of neurotransmitters?

nucleic acid

Which of the following is not a chemical class of neurotransmitters? A) biogenic amine B) nucleic acid C) amino acid D) ATP and other purines

nucleic acid

schwann cells are functionally similar to...

olidendrocytes

Schwann cells are functionally similar to ________.

oligodendrocytes

Schwann cells are functionally similar to ________. A) astrocytes B) microglia C) ependymal cells D) oligodendrocytes

oligodendrocytes

Which of the following types of glial cells produces the myelin sheaths that insulate axons, or nerve fibers, in the central nervous system (CNS)?

oligodendrocytes

What characterizes repolarization, the second phase of the action potential? a) as the membrane repolarizes to a negative value, it goes beyond the resting state to a value of -80 mV b) before the membrane has a chance to reach a positive voltage, it repolarizes to its negative resting value of approximately -70 mV c) once the membrane depolarizes to a peak value of +30 mV, it repolarizes to its negative resting value of -70 mV d) once the membrane depolarizes to a threshold value of approximately -55 mV, it repolarizes to its resting value of -70 mV

once the membrane depolarizes to a peak value of +30 mV, it repolarizes to its negative resting value of -70 mV

Second messengers can

open and close ions channels, activate kinase enzymes, and phosphorylate channel proteins

Direct-acting neurotransmitters ________.

open ion channels to provoke rapid responses

The Peripheral Nervous System (PNS) is the part of the nervous system that is located_______ the CNS.

outside

20) The sinoatrial node, located in the right atrium of the heart, is often called the __________.

pacemaker

5. Spinal nerves and cranial nerves are both components of the

peripheral nervous system

6. Ganglia are a part of the

peripheral nervous system

44) The amount of friction blood encounters as it flows through the blood vessels is known as __________.

peripheral resistance

Immediately after an action potential has peaked, which cellular gates open?

potassium

During the repolarization of a neuron: a) sodium ions move out of the cell b) potassium ions move out of the cell c) potassium ions move into the cell d) sodium ions move into the cell

potassium ions move out of the cell

Which of the following is NOT a type of circuit?

pre-discharge circuits

Which best represents synaptic transmission?

presynaptic axon to synapse to dendrite or postsynaptic cell body

In a synapse, neurotransmitters are stored in vesicles located in the ____________. a) presynaptic neuron b) postsynaptic neuron c) synaptic cleft

presynaptic neuron

The sodium-potassium pump uses ATP to move sodium and potassium ions across the plasma membrane. This statement describes _____.

primary active transport

Which of the following is not a function of astrocytes? A. anchor neurons to blood vessels B. support and brace neurons C. provide the defense for the CNS D. control the chemical environment around neurons E. guide the migration of young neurons, synapse formation, and helping to determine capillary permeability

provide the defense for the CNS

16) The circulation from the heart to the lungs and back is known as __________ circulation.

pulmonary

The sodium-potassium pump ________.

pumps three sodium ions outside the cell and two potassium ions inside.

Which of the following processes allows cells to concentrate material that is present only in very small amounts in the extracellular fluid?

receptor-mediated endocytosis

8. Autonomic nervous system consists of visceral motor nerve fibers that

regulate smooth muscle, are apart of the parasympathetic nervous system, regulate cardiac muscle

Which of the following is NOT one of the basic functions of the nervous system?

regulation of neurogenesis

Which is not a one of the basic functions of the nervous system? a. monitor changes occurring both inside & outside the body b. control the activity of muscle and glands c. regulation of neurogenesis d integration of sensory input

regulation of neurogenesis is not one of the basic functions of the nervous system

37. The down slope on an AP graph represents

repolarization phase

Ions are unequally distributed across the plasma membrane of all cells. This ion distribution creates an electrical potential difference across the membrane. What is the name given to this potential difference?

resting membrane potential

Ions are unequally distributed across the plasma membrane of all cells. This ion distribution creates an electrical potential difference across the membrane. What is the name given to this potential difference? a) action potential b) resting membrane potential (RMP) c) threshold potential d) positive membrane potential

resting membrane potential (RMP)

In addition to diffusion, what are two other mechanisms that terminate neurotransmitter activity?

reuptake and degragation

47. Neurotransmitter effects are terminated how

reuptake by astrocytes or axon terminal degradation by enzymes diffusion away from the synaptic cleft

A neural circuit in which a single impulse is transmitted over and over is a ________.

reverberating circuit

Which neuron circuit pattern is involved in the control of rhythmic activities such as breathing?

reverberating circuit

neural circuit in which a single impulse is transmitted over and over is a ________.

reverberating circuit

The node-to-node "jumping" regeneration of an action potential along a myelinated axon is called __________.

salatory conduction

The type of action potential propagation in which action potentials are only generated at nodes of Ranvier is called ___________. a) saltatory conduction b) synaptic transmission c) unmyelinated conduction d) continuous conduction

saltatory conduction

10. All of the following are found in the central nervous system except

satellite cells

Cranial nerve II, the optic nerve sends nerve impulses to the brain carrying information about the things we see. These nerve fibers most likely belong to which division of the nervous system? A) sensory (afferent) division B) somatic nervous system C) sympathetic division D) parasympathetic division

sensory (afferent) division

46. The synaptic cleft

separates the presynaptic from the postsynaptic neurons

Which pattern of neural processing works in a predictable, all-or-nothing manner, where reflexes are rapid and automatic responses to stimuli in which a particular stimulus always causes the same response?

serial processing

Which of the following describes the excitatory postsynaptic potential?

short distance depolarization

Which of the following describes the excitatory postsynaptic potential? A) moves membrane potential away from threshold B) opens K+ or Cl- channels C) short distance depolarization D) short distance hyperpolarization

short distance depolarization

Which of the following is controlled by the somatic motor division? a) smooth muscle b) cardiac muscle c) glands d) skeletal muscle

skeletal muscle

Hyperpolarization results from ___________. a) slow closing of voltage-gated Na+ channels b) slow closing of voltage-gated K+ channels c) fast closing of voltage-gated K+ channels

slow closing of voltage-gated K+ channels

hyperpolarization results from...

slow closing voltage gated K+ channels

Which of the following is least likely to increase the rate of diffusion?

small concentration gradient

Which of the following best characterizes depolarization?

small consecutive steps of Na+ penetration into the axon along its length

Which of the following is true about the movement of ions across excitable living membranes?

sodium gates in the membrane can open in response to electrical potential changes

Sarah sensed a mosquito land on her arm and swatted it away with her hand. Which specific PNS division was responsible for the movement of Sarah's hand? a) somatic motor division b) visceral sensory division c) somatic sensory division d) autonomic nervous system

somatic motor division

The somatic nervous system is composed of?

somatic motor nerve fibers that conduct impulses from the central nervous system to skeletal muscles. It is often referred to as the voluntary nervous system because it allows us to consciously control our skeletal muscles

Upon entering your house, you noticed the smell of cake baking in the oven. What division of the peripheral nervous system is responsible? a) somatic sensory division b) somatic motor division c) visceral motor division d) visceral sensory division

somatic sensory division

Changes in membrane potential that cancel each other are likely are result of

spacial summation of EPSP and IPSPsy

An impulse from one nerve cell is communicated to another nerve cell via the ________.

synapse

The small space between the sending neuron and the receiving neuron is the: a) vesicle b) synaptic terminal c) neurotransmitter d) calcium channel e) synaptic cleft

synaptic cleft

The time needed for neurotransmitter to release and diffuse across the synapse is called the

synaptic delay

If a signal from a sending neuron makes the receiving neuron more negative inside, a) the receiving neuron is less likely to generate an action potential b) the receiving neuron is more likely to generate an action potential c) the receiving neuron immediately generates an action potential d) the sending neuron becomes more negative inside e) the sending neuron becomes more positive inside

the receiving neuron is less likely to generate an action potential

If a signal from a sending neuron makes the receiving neuron more negative inside,

the receiving neuron is less likely to generate an action potential.

A neurotransmitter may have an excitatory or an inhibitory effect on the postsynaptic cell, depending on ____________. a) which class of neurotransmitters it belongs to b) the quantity of neurotransmitter released c) the receptor to which it binds d) the frequency of neurotransmitter release

the receptor to which it binds

During an action potential, the rapid decrease in sodium permeability and simultaneous increase in potassium permeability is responsible for __________. a) the depolarization phase b) returning to the resting membrane potential after the action potential c) the repolarization phase d) the hyperpolarization phase

the repolarization phase

33. What system stabilizes a resting membrane

the sodium potassium pump

What is the electrochemical gradient of an ion?

the sum of the electrical and concentration gradients for that ion

In the axon hillock, slow depolarization to threshold is due to ____________. a) the summation of EPSPs b) the opening of Na+ voltage-gated channels c) the opening of K+ voltage-gated channels d) the summation of IPSPs

the summation of EPSPs

During the relative refractory period of an action potential, a larger than normal stimulus is needed to cause another action potential. This is due to the fact that ________. A) the voltage gated potassium ion channels remain open long enough to hyperpolarize the axon membrane B) the membrane is now impermeable to all ions C) the sodium potassium pump will stop working during relative refractory D) the inactivation gates on voltage gated sodium ion channels are closed

the voltage gated potassium ion channels remain open long enough to hyperpolarize the axon membrane

The plasma membrane is much more permeable to K+ than to Na+. Why? a) there are many more voltage-gated K+ channels than voltage-gated Na+ channels b) ligand-gated cation channels favor a greater influx of Na+ than K+ c) there are many more K+ leak channels than Na+ leak channels in the plasma membrane d) the Na+-K+ pumps transport more K+ into cells than Na+ out of cells

there are many more K+ leak channels than Na+ leak channels in the plasma membrane

Which of the following is not characteristic of neurons?

they are mitotic

When calcium ions enter the synaptic terminal, a) they cause an action potential in the sending neuron b) the inside of the receiving neuron becomes more negative c) the inside of the receiving neuron becomes more positive d) they cause vesicles containing neurotransmitter molecules to fuse to the plasma membrane of the sending neuron e) neurotransmitter molecules are quickly removed from the synaptic cleft

they cause vesicles containing neurotransmitter molecules to fuse to the plasma membrane of the sending neuron

When calcium ions enter the synaptic terminal,

they cause vesicles containing neurotransmitter molecules to fuse to the plasma membrane of the sending neuron.

35) Inflammation of varicose veins can result in a clot in that vessel; this condition is referred to as __________.

thrombophlebitis

23. Proximal processes form unipolar cells head

to the central nervous system

43. Presynaptic neurons conduct information

toward the synapse

17. which of the following is a term for a bundle of neuron processes

tracts and nerves

True/False 21) The three branches of the aortic arch are the brachiocephalic trunk, left common carotid artery, and the left subclavian artery.

true

True/False 29) In fetal circulation, blood travels directly from the right atrium to the left atrium through the foramen ovale.

true

efferent nerves may be described as motor nerve fibers.

true

31) The innermost blood vessel wall that lines the lumen and consists of cells that fit closely together to form a slick surface that decreases friction and allows blood to flow smoothly is the __________.

tunica intima

Which of the following is NOT one of the mechanisms for synaptic transmission termination? a) diffusion of neurotransmitter away b) uptake of neurotransmitter into postsynaptic neuron c) reuptake of neurotransmitter into presynaptic neuron d) degradation of neurotransmitter by enzyme

uptake of neurotransmitter into postsynaptic neuron

33) Larger veins have __________ to prevent the backflow of blood.

valves

45) The narrowing of blood vessels is known as __________.

vasoconstriction

41) The umbilical cord contains an umbilical __________ that transports oxygen and nutrientrich blood to the fetus.

vein

26. The measure of potential energy generated by separated charges is the definition of

voltage

the depolarization phase of an action potential results from the opening of which channels?

voltage gated Na+ channels

Immediately after an action potential has peaked, which of the following channels will open? A) voltage gated calcium channels B) chemically gated chloride channels C) voltage gated potassium channels D) voltage gated sodium channels

voltage gated potassium channels

An action potential releases neurotransmitter from a neuron by opening which of the following channels? a) chemically gated Ca2+ channels b) voltage-gated Ca2+ channels c) voltage-gated K+ channels d) voltage-gated Na+ channels

voltage-gated Ca2+ channels

The channels that open when the axolemma reaches threshold depolarization are the: a) voltage-gated K ion channels b) voltage-gated Na ion channels c) chemically gated K ion channels d) chemically gated Na ion channels

voltage-gated Na ion channels

The depolarization phase of an action potential results from the opening of which channels? a) voltage-gated Na+ channels b) chemically gated K+ channels c) voltage-gated K+ channels d) chemically gated Na+ channels

voltage-gated Na+ channels

what opens first in resonse to a threshold stimulus? a) voltage-gated Na+ channels b) ligand-gated cation channels c) ligand-gated Cl- channels d) voltage-gated K+ channels

voltage-gated Na+ channels

What is the first change to occur in response to a threshold stimulus? a) voltage-gated Na+ channels change shape, and their inactivation gates close b) voltage-gated K+ channels change shape, and their activation gates open c) voltage-gated Ca2+ channels change shape, and their activation gates open d) voltage-gated Na+ channels change shape, and their activation gates open

voltage-gated Na+ channels change shape, and their activation gates open

Which ion channel opens in response to a change in membrane potential and participates in the generation and conduction of action potentials?

voltage-gated channel

The generation of an action potential in a neuron requires the presence of what type of membrane channels? a) voltage-gated channels b) chemically gated channels c) leakage channels d) membrane channels are not required

voltage-gated channels

When an action potential arrives at the end of the axon terminal, a series of events take place that result in the release of neurotransmitter from the presynaptic axon. Select the answer that correctly describes the primary stimulus for vesicles to move towards the cell membrane and eventually release their contents.

voltage-gated membrane channels open, and Ca+2 enters the cytoplasm, increasing intracellular calcium

59. A converging circuit is

when different sensory stimuli elicit the same memory

12. Myelin is associated with the

white matter

Myelinated axons in the CNS are known as: a) dark matter b) internodes c) gray matter d) white matter

white matter

Matching 1) Heart chamber with the 2) Superior discharging 3) Heart chamber that pumps 4) Heart chamber that contains the sinoatrial node 5) Roof of this chamber contains the bicuspid valve 6) The coronary sinus empties blood from cardiac circulation into this chamber 7) The four pulmonary veins return oxygenated blood to this chamber 8) This chamber sends blood into the aorta A) right atrium thickest wall B) right ventricle C) right atrium chamber on the left side of the heart D) left ventricle E) left atrium blood to the pulmonary trunk

1) D 2) D 3) B 4) C 5) D 6) A 7) E 8) D

Identify the sequence of events that occurs at a synapse. 1. An action potential arrives at the synaptic terminal 2. Vesicles containing neurotransmitter fuse with the plasma membrane of the sending neuron 3. Neurotransmitter molecules diffuse across the synaptic cleft 4. The neurotransmitter molecules bind to receptors in the plasma membrane of the receiving neuron, causing ion channels there to open 5. Calcium channels open, and calcium ions enter the synaptic terminal

1, 5, 2, 3, 4

Which of the neuroglial cell types form myelin sheaths within the CNS?

Oligodendrocytes form myelin sheaths within the white matter of the CNS

Define: Oligodendrocytes

Oligodendrocytes wrap their processes around the thicker axons in the CNS, producing an insulating covering called a myelin sheath that increases the transmission speed of nerve impulses.

What characterizes repolarization, the second phase of the action potential?

Once the membrane depolarizes to a peak value of +30 mV, it repolarizes to its negative resting value of -70 mV.

22) The electrocardiogram (ECG) wave that results from depolarization of the atria is the __________.

P wave

How do action potential propagation speeds compare in myelinated and unmyelinated axons?

Propagation is faster in myelinated axons.

Which of the following is true about the movement of ions across excitable living membranes? A) Ions always move actively across membranes through leakage channels. B) Sodium gates in the membrane can open in response to electrical potential changes. C) Ions always move from an area of higher concentration to an area of lower concentration. D) Ions always move passively across membranes.

Sodium gates in the membrane can open in response to electrical potential changes.

Which of the following is NOT a difference between graded potentials and action potentials?

Spatial summation is used to increase the amplitude of a graded potential; temporal summation is used to increase the amplitude of an action potential.

Local anesthetics block voltage-gated Na+ channels, but they do not block mechanically gated ion channels. Sensory receptors for touch (and pressure) respond to physical deformation of the receptors, resulting in the opening of specific mechanically gated ion channels. Why does injection of a local anesthetic into a finger still cause a loss of the sensation of touch from the finger?

Touch stimulation of this sensory receptor will open the mechanically gated ion channels, but action potentials are still not initiated because propagation of an action potential requires the opening of voltage-gated Na+ channels.

Which statement best characterizes a leak channel?

Trans-membrane protein channels that are always open to allow to cross the membrane without the additional input of energy.

A postsynaptic potential is a graded potential that is the result of a neurotransmitter released into the synapse between two neurons.

True

A stimulus traveling toward a synapse appears to open calcium ion channels at the presynaptic end, which in turn promotes fusion of synaptic vesicles to the axonal membrane.

True

Axon diameter and degree of myelination determine nerve impulse conduction velocity.

True

Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.

True

During depolarization, the inside of the neuron's membrane becomes less negative.

True

During depolarization, the inside of the neurons's membrane becomes LESS negative T/F

True

Efferent nerve fibers may be described as motor nerve fibers.

True

Enkephalins and endorphins are peptides that act like morphine.

True

If bacteria invaded the CNS tissue, microglia would migrate to the area to engulf and destroy them.

True

In myelinated axons the voltage-regulated sodium channels are concentrated at the nodes of Ranvier.

True

Large-diameter nerve fibers conduct impulses much faster than small-diameter fibers.

True

Myelination of the nerve fibers in the central nervous system is the job of the oligodendrocyte.

True

Neurons are also called nerve cells.

True

Neurons in the CNS are organized into functional groups.

True

Opening K+ or Cl- channels in a postsynaptic membrane would produce an inhibitory postsynaptic potential (IPSP).

True

Reflexes are rapid, automatic responses to stimuli that will produce the dame effect every time.

True

Reflexes are rapid, automatic responses to stimuli.

True

Some neurotransmitters can be either excitatory or inhibitory depending upon the receptor.

True

Which of the following statements is correct regarding the polarization of a neuronal membrane and the formation of a resting membrane potential? a. As Na+ leaks across the membrane, that establishes a negative charge inside the membrane. b. Sodium/Potassium pumps maintain concentration gradients; sodium and potassium move down their concentration gradients through leakage channels. c. As sodium leaks into the cell, the inside of the cell becomes more negative. d. A resting potential can be generated without the energy as an input.

b. Sodium/Potassium pumps maintain concentration gradients; sodium and potassium move down their concentration gradients through leakage channels.

The period after an initial stimulus when a neuron is NOT sensitive to stimulus is the _________. a. depolarization b. absolute refractory period c. repolarization d. resting period

b. absolute refractory period

Which of the following describes the nervous system integrative function? a. senses changes in the environment b. analyzes sensory information, stores information, makes decisions c. responds to stimuli by gland secretion or muscle contraction

b. analyzes sensory information, stores information, makes decisions

Cold sores on the skin of the mouth occur when herpes simplex viruses that are dormant in neural ganglia become active and travel to the skin of the mouth. Which of the following is the mechanism by which these viruses travel from the ganglia (located within the head) to the skin of the mouth? a. transport along nerve impulses that travel down the axons b. anterograde axonal transport c. retrograde axonal transport d. travel of the viruses along neurofibrils

b. anterograde axonal transport

A neuron that has as its primary function the job of connecting other neurons is called a(n) _________. a. efferent neuron b. association neuron c. glial cell d. afferent neuron

b. association neuron

Which of the following will occur when an excitatory postsynaptic potential (EPSP) is being generated on the dendritic membrane? a. Sodium gates will open first, then close as potassium gates open. b. Specific sodium gates will open. c. A single type of channel will open, permitting simultaneous flow of sodium and potassium. d. Specific potassium gates will open.

c. A single type of channel will open, permitting simultaneous flow of sodium and potassium.

Neurotransmitters classified by function are grouped into 2 classifications

effects or actions

Binding of the neurotransmitter to its receptor causes the membrane to _____________. a) depolarize b) either depolarize or hyperpolarize c) hyperpolarize

either depolarize or hyperpolarize

What changes occur to the voltage-gated Na+ and K+ channels at the peak of depolarization? a) inactivation gates of voltage-gated Na+ channels close, while activation gates of voltage-gated K+ channels open b) activation gates of voltage-gated Na+ channels close, while activation gates of voltage-gated K+ channels open c) inactivation gates of voltage-gated Na+ channels close, while inactivation gates of voltage-gated K+ channels open d) activation gates of voltage-gated Na+ channels close, while inactivation gates of voltage-gated K+ channels open

inactivation gates of voltage-gated Na+ channels close, while activation gates of voltage-gated K+ channels open

15) A decrease in the elasticity of blood vessels (i.e., increase in rigidity) causes arterial blood pressure to __________.

increase

28) The hormones epinephrine and thyroxine will cause the heart rate to __________.

increase

If a drug inhibits the enzyme Acetylcholinesterase, the effect will be: a) decreased stimulation of ACh receptors b) increased ACh reuptake into presynaptic cell c) increased ACh availability in synaptic cleft d) increased levels of ACh inside synaptic vesicles

increased ACh availability in synaptic cleft

37) The vessel that drains blood from all body regions below the diaphragm muscle before emptying into the right atrium is the __________.

inferior vena cava

Where do most action potentials originate? a) axon terminal b) cell body c) Nodes of Ranvier d) initial segment

initial segment

Which of the following is not a function of the autonomic nervous system? A innervation of cardiac muscle B innervation of skeletal muscle C innervation of glands D innervation of smooth muscle of the digestive tract

innervation of skeletal muscle

What component of the reflex arc determines the response to a stimulus?

integration center

What type of neuron is found within the CNS to perform the job of information processing? a) interneurons (association neurons) b) motor (efferent) neurons c) bipolar neurons d) sensory (afferent) neurons

interneurons (association neurons)

7) The partition where the bundle branches are located is called the __________.

interventricular septum

Autonomic Nervous System (ANS) is also called the

involuntary nervous system

When neurotransmitter molecules bind to receptors in the plasma membrane of the receiving neuron, a) vesicles in the synaptic terminal fuse to the plasma membrane of the sending neuron b) ion channels in the plasma membrane of the sending neuron open c) the receiving neuron becomes more positive inside d) the receiving neuron becomes more negative inside e) ion channels in the plasma membrane of the receiving neuron open

ion channels in the plasma membrane of the receiving neuron open

When neurotransmitter molecules bind to receptors in the plasma membrane of the receiving neuron,

ion channels in the plasma membrane of the receiving neuron open.

Learning or memory is a result of

synaptic potentiation

24) The term that means heart contraction is __________.

systole

23) A heart rate over 100 beats per minute is referred to as __________.

tachycardia

Why does the action potential only move away from the cell body? a) the flow of the sodium ions only goes in one direction - away from the cell body b) the areas that have had the action potential are refractory to a new action potential

the ares that have had the action potential are refractory to a new action potential

which areas of the neuron would be classified as receptive regions?

the cell body and dendrites

which criterion is used to functionally classify neurons?

the direction in which the nerve impulse travels relative to the central nervous system

Imagine you changed the concentration of K+ outside a neuron such that the resting membrane potential changed to -80 mV (from the normal resting value of -70 mV). What have you changed?

the electrical gradient for K+ and the concentration gradient for K+

39. When coding for stimulus intensity

the frequency of impulses in registered in the CNS

An action potential in one segment of axon causes adjacent sections of axon membrane to reach threshold through what mechanism?

the generation of local currents

If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon ________.

the impulse would spread bidirectionally

If a motor neuron in the body were stimulated by an electrode placed about midpoint along the length of the axon ________. A) the impulse would move to the axon terminal only, and the muscle contraction would occur B) the impulse would spread bidirectionally C) muscle contraction would occur D) the impulse would move to the axon terminal only

the impulse would spread bidirectionally

Why does regeneration of the action potential occur in one direction, rather than in two directions?

the inactivation gates of voltage gated Na+ channels close in the node, or segment that has just fired an action potential

Why does regeneration of the action potential occur in one direction, rather than in two directions? a) the activation gates of voltage-gated Na+ channels close in the node, or segment, that has just depolarized b) the inactivation gates of voltage-gated Na+ channels close in the node, or segment, that has just fired an action potential c) the activation gates of voltage-gated K+ channels open in the node, or segment, that has just depolarized d) the inactivation gates of voltage-gated K+ channels close in the node, or segment, that has just fired an action potential

the inactivation gates of voltage-gated Na+ channels close in the node, or segment, that has just fired an action potential

On average, the resting membrane potential is -70 mV. What does the sign and magnitude of this value tell you? a) the inside surface of the plasma membrane is much more positively charged than the outside surface b) the inside surface of the plasma membrane is much more negatively charged than the outside surface c) the outside surface of the plasma membrane is much more negatively charged than the inside surface d) there is no electrical potential difference between the inside and the outside surfaces of the plasma membrane

the inside surface of the plasma membrane is much more negatively charged than the outside surface

What characterizes depolarization, the first phase of the action potential? a) the membrane potential changes to a much more negative value b) the membrane potential changes from a negative value to a positive value c) the membrane potential reaches a threshold value and returns to the resting state d) the membrane potential changes to a less negative (but not a positive) value

the membrane potential changes from a negative value to a positive value

A second nerve impulse cannot be generated until ________. A) all sodium gates are closed B) the membrane potential has been reestablished C) the Na ions have been pumped back into the cell D) proteins have been resynthesized

the membrane potential has been reestablished

What event triggers the generation of an action potential? a) the membrane potential must hyperpolarize from the resting voltage of -70 mV to the more negative value of -80 mV b) the membrane potential must return to its resting value of -70 mV from the hyperpolarized value of -80 mV c) the membrane potential must depolarize from the resting voltage of -70 mV to a threshold value of -55 mV d) the membrane potential must depolarize from the resting voltage of -70 mV to its peak value of +30 mV

the membrane potential must depolarize from the resting voltage of -70 mV to a threshold value of of -55 mV

Saltatory conduction is made possible by ________. A) erratic transmission of nerve impulses B) diphasic impulses C) large nerve fibers D) the myelin sheath

the myelin sheath

What is the function of the myelin sheath? a) the myelin sheath increases the speed of action potential conduction from the initial segment to the axon terminals b) the myelin sheath decreases the speed of action potential conduction from the initial segment to the axon terminals c) the myelin sheath increases the insulation along the entire length of the axon d) the myelin sheath decreases the resistance of the axonal membrane to the flow of charge

the myelin sheath increases the speed of action potential conduction from the initial segment to the axon terminals

what is the function of the myelin sheath?

the myelin sheath increases the speed of action potential from the initial segment to the axon terminals

2. The master controlling and communicating system of the body is

the nervous system

In a myelinated axon, how do the nodes of Ranvier differ from other segments of the same axon?

the nodes are more permeable to ions

the repolarization phase of an action potential results from....

the opening of voltage gated K+ channels

The repolarization phase of an action potential results from ___________. a) the closing of voltage-gated K+ channels b) the closing of voltage-gated Na+ channels c) the opening of voltage-gated K+ channels d) the opening of voltage-gated Na+ channels

the opening of voltage-gated K+ channels

38. The refractory period is

the period where another action potential cannot be produced the period of hyperpolarization

A neuron that receives neurotransmitters from another neuron is called: a) a Schwann cell b) the presynaptic neuron c) the postsynaptic neuron d) an oligodendrocyte

the postsynaptic neuron

The resting membrane potential depends on two factors that influence the magnitude and direction of Na+ and K+ diffusion across the plasma membrane. Identify these two factors. a) the presence of concentration gradients and Na+-K+ pumps b) the presence of a resting membrane potential and leak channels c) the presence of concentration gradients and leak channels d) the presence of concentration gradients and voltage-gated channels

the presence of concentration gradients and leak channels

If a post synaptic neuron is stimulated to threshold by spatial summation this implies that ________. A) the post synaptic cell has a lower than normal threshold B) the post synaptic cell has many voltage gated ion channels C) the post synaptic cell is slow to repolarize D) the postsynaptic cells has many synapses with many presynaptic neurons

the postsynaptic cells has many synapses with many presynaptic neurons

Reflexes are rapid, automatic responses to stimuli that will produce the same effect every time.

true

An action potential is regarded as an example of a positive feedback. Which of the following examples below best illustrates the positive feedback aspect of an action potential? A) The sodium potassium pump consistently moves ions as long as ATP is available, and regardless of membrane potential changes. B) Potassium permeability is about 25 times greater than sodium ions. C) Voltage gated potassium ion channels open slowly and remain open long enough to cause hyperpolarization. D) A threshold stimulus will cause the opening of voltage gated sodium ion channels that will cause further depolarizing stimulus. This stimulus will open still more voltage gated sodium ion channels.

A threshold stimulus will cause the opening of voltage gated sodium ion channels that will cause further depolarizing stimulus. This stimulus will open still more voltage gated sodium ion channels.

Select the correct statement about synapses. A) The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another. B) Neurotransmitter receptors are located on the axons of cells. C) The release of neurotransmitter molecules gives cells the property of being electrically coupled. D) Cells with interconnected cytoplasm are chemically coupled.

A) The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another.

Conducting region of the neuron.

Axon

Neurotransmitters are released at the ________.

Axon terminal

Receives stimuli. A) Secretory zone B) Conducting region C) Secretory region D) Trigger zone E) Receptive region

Receptive region

Which of the following is true about the movement of ions across excitable living membranes? A) The bulk of the solutions inside a cell are negatively charged. B) Ions always move actively across membranes through leakage channels. C) Some ions are prevented from moving down their concentration gradients by ATP-driven pumps. D) Sodium gates in the membrane can open in response to electrical potential changes.

C) Some ions are prevented from moving down their concentration gradients by ATP-driven pumps.

Choose the statement that is most correct about membrane potential. A) Voltage would be measured by placing one electrode on one end of the axon and another electrode on the other end. B) Voltage would be measured by placing one electrode on the axon and grounding the other electrode. C) Voltage would be measured by placing two electrodes on the exterior of the axon. D) Voltage would be measured by placing one electrode inside the membrane and another outside the membrane.

D) Voltage would be measured by placing one electrode inside the membrane and another outside the membrane.

All of the following are true of graded potentials except that they ________. A) can be called postsynaptic potentials B) are short-lived C) can form on receptor endings D) increase amplitude as they move away from the stimulus point

D) increase amplitude as they move away from the stimulus point

Which of the following is not a structural feature of a neuron? A) Nissl bodies B) dendrites C) axon D) synaptic cleft

D) synaptic cleft

Multiple sclerosis (MS) is a disease in which the myelin sheaths are destroyed. What process does this interfere with and what would be the consequence?

Demyelination interferes with saltatory conduction, which would result in a slowing down of nerve impulse propagation.

The effect of acetylcholine can be stimulating or inhibiting. Which of the following gives the best explanation for why this is so? A) Acetylcholine has many different forms. B) Acetylcholine has a "dose effect". Larger doses are stimulating while small doses inhibit. C) Postsynaptic cells have a dynamic and changing metabolism and respond differently at different times. D) Different post synaptic cells will have different receptors.

Different post synaptic cells will have different receptors.

________ is an indolamine.

Epinephrine

The nodes of Ranvier are found only on myelinated, peripheral neural processes.

False

Plasma membrane exhibits chemically gated ion channels. A) Secretory zone B) Conducting region C) Secretory region D) Trigger zone E) Receptive region

Receptive region

Plasma membrane exhibits voltage-gated Ca2+ channels. A) Secretory zone B) Conducting region C) Secretory region D) Trigger zone E) Receptive region

Secretory region

A client was admitted for depression. What should the nurse explain to the client regarding the role of serotonin and depression?

Serotonin is a biogenic amine neurotransmitter widely distributed in the brain, where it plays a role in emotional behavior and helps to regulate the biological clock.

Stimulation of a postsynaptic neuron by many terminals at the same time.

Spatial summation

Stimulation of a postsynaptic neuron by many terminals at the same time. A) Spatial summation B) Subthreshold stimulus C) Threshold stimulus D) Temporal summation

Spatial summation

An insufficient stimulus to reach an action potential. A) Spatial summation B) Subthreshold stimulus C) Threshold stimulus D) Temporal summation

Subthreshold stimulus

An insufficient stimulus.

Subthreshold stimulus

Which of the following is not characteristic of neurons? A) They have an exceptionally high metabolic rate. B) They conduct impulses. C) They have extreme longevity. D) They are mitotic.

They are mitotic.

The depolarization phase of an action potential is punctuated by the closing of inactivation gates in the voltage gated sodium ion channels. All of the following are consequences of this inactivation except one. Choose the statement below that is not a consequence of the closing of inactivating gates. A) This allows for the efflux (diffusion out) of potassium ions, resulting in the repolarization of the cell. B) This allows for the one way transmission of action potential down the axon. C) This limits the frequency of action potentials down the axon. D) This stops the depolarization of the axon membrane.

This allows for the efflux (diffusion out) of potassium ions, resulting in the repolarization of the cell.

Any stimulus at or above this level will result in action potential. A) Spatial summation B) Subthreshold stimulus C) Threshold stimulus D) Temporal summation

Threshold stimulus

Any stimulus below this intensity will result in no response in a neuron.

Threshold stimulus

Area where nerve impulse is generated. A) Secretory zone B) Conducting region C) Secretory region D) Trigger zone E) Receptive region

Trigger zone

32) Cell bodies of sensory neurons may be located in ganglia lying outside the central nervous system.

True

A graded potential that is the result of a neurotransmitter released into the synapse between two neurons is called a postsynaptic potential.

True

A stimulus traveling toward a synapse appears to open calcium channels at the presynaptic end, which in turn promotes fusion of synaptic vesicles to the axonal membrane.

True

A synapse formed between the axon ending of one neuron and the cell body of another neuron is called an axosomatic synapse.

True

Acetylcholine is not a biogenic amine.

True

The period after an initial stimulus when a neuron is not sensitive to another stimulus is the ________. A) repolarization B) resting period C) absolute refractory period D) depolarization

absolute refractory period

Bacteria in the blood can be prevented entry to the fluids surrounding the brain. Which cells are most responsible for preventing bacteria from entering the fluids of the brain? A) satellite cells B) astrocytes C) Schwann cells D) oligodendrocytes

astrocytes

The concentration neurotransmitters in the fluid of the synaptic cleft must be tightly regulated for neurons to function properly. Which of the following cells is most responsible for aiding in this regulation? A) satellite cells B) astrocytes C) Schwann cells D) oligodendrocytes

astrocytes

The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated for neurons to function properly. Which of the following cells is most responsible for this? A) satellite cells B) astrocytes C) Schwann cells D) oligodendrocytes

astrocytes

The sympathetic and parasympathetic are subdivisions of the _____.

autonomic nervous system

A neuronal circuit that concentrates or directs a large number of incoming impulses to a rather small number of neurons is called a(n) _______.

converging circuit

Ciliated CNS neuroglia that play an active role in moving the cerebrospinal fluid are called ________.

ependymal cells

These cells in the CNS have cilia that move in order to circulate cerebrospinal fluid ________. A) ependymal cells B) astrocytes C) oligodendrocytes D) Schwann cells

ependymal cells

Bipolar neurons are commonly ________. A) motor neurons B) called neuroglial cells C) found in the retina of the eye D) found in ganglia

found in the retina of the eye

An inhibitory postsynaptic potential (IPSP) is associated with _______.

hyperpolarization

When a neurotransmitter like GABA is acting in an inhibitory manner which of the following is likely a result of the GABA acting on the post synaptic cell? A) influx of positively charged ions into the postsynaptic cell B) opening of chemically gated sodium channels C) depolarization of the postsynaptic cell membrane D) hyperpolarization of the postsynaptic cell membrane

hyperpolarization of the postsynaptic cell membrane

Loss of function in the enzyme acetylcholine esterase would result in which of the following? A) inability to destroy and remove acetylcholine from the synaptic cleft B) stimulation of the production of acetylcholine C) amplify or enhance the effect of ACh D) inability to release acetylcholine

inability to destroy and remove acetylcholine from the synaptic cleft

Which of the following is not a function of the autonomic nervous system? A) innervation of smooth muscle of the digestive tract B) innervation of skeletal muscle C) innervation of cardiac muscle D) innervation of glands

innervation of skeletal muscle

An action potential _____.

is essential for impulse propagation

Meningitis can be caused by infection of the central nervous system by bacteria. Which cells would be most responsible for removing the infection? A) Schwann cells B) oligodendrocytes C) microglia D) satellite cells

microglia

Which of the choices below describes the ANS? A) motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands B) motor fibers that conduct nerve impulses from the CNS to skeletal muscles C) sensory and motor neurons that supply the digestive tract D) sensory neurons that convey information from somatic receptors in the head, body wall, and limbs and from receptors from the special senses of vision, hearing, taste, and smell to the CNS

motor fibers that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands

Nerve impulses are sent to slow the heart's rate of contraction. The nerve fibers sending these signals will most likely belong to which division of the nervous system? A) sensory (afferent) division B) somatic nervous system C) sympathetic division D) parasympathetic division

parasympathetic division

Nerve impulses leading to the brain carry information about cool temperatures on the skin.The nerve fibers sending these signals will most likely belong to which division of the nervous system? A) sensory (afferent) division B) somatic nervous system C) sympathetic division D) parasympathetic division

sensory (afferent) division

Nerve impulses leading to the skeletal muscle carry information to direct movement. The nerve fibers sending these signals will most likely belong to which division of the nervous system? A) sensory (afferent) division B) somatic nervous system C) sympathetic division D) parasympathetic division

somatic nervous system

The point at which an impulse from one nerve cell is communicated to another nerve cell is the _______.

synapse


Conjuntos de estudio relacionados

contribution to lower flexibility

View Set

NURS 420 community health practice test 4 (Ch 25-32)

View Set

Chapter 14: The Newborn with a Perinatal Injury or Congenital Malformation

View Set

Pharmacology PrepU; Chapter 22- Psychotherapeutic Agents #5

View Set