Mastering Module I PDF

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Questions from the Mastering modules to study...

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Module 1: Concept Map: Feedback Mechanisms Part A

Part B: Which of the following is an example of positive feedback? a.) b.) c.) d.)

the increase in milk production while a mother is nursing her infant sweating when hot so that as sweat evaporates the body is cooled breathing and heart rate increase as a person climbs a set of stairs constriction of the pupils when the eyes are exposed to bright light

Part C: Which of the following is a typical effector in a feedback system? a.) b.) c.) d.)

pressure-sensitive cells in the blood vessel walls temperature-sensitive nerve endings in the skin an endocrine gland the brain

Part D: Which of the following represents activation of an “afferent” pathway? a.) b.) c.) d.)

jerking the hand back in a reflex action increasing the production of chemicals that attract more platelets to produce a blood clot sending a signal to sweat glands to produce sweat the perception of being in a cold environment

Part E: The cruise control in a car monitors the car’s speed and adjusts the accelerator as needed to maintain the speed at a set point determined by the driver. Which of the following would serve as the receptor in this feedback system? a.) b.) c.) d.)

the car’s accelerator the computer chip within the cruise control device that compares actual speed to desired speed the car’s tires the car’s speedometer

Get Ready for A&P Video Tutor: Cell Membrane Structure Part A: Which of the following is the main component of the cell membrane? a.) b.) c.) d.)

phospholipids carbohydrates water cholesterol

Part B: Which of the following is a characteristic of the cell membrane? a.) b.) c.) d.)

impermeable fully permeable semipermeable not permeable

Part C: Which of the following is not a major function of proteins in the cell membrane? a.) b.) c.) d.)

forming the entire glycocalyx anchoring cells to other structures forming channels acting as receptors

Part D: What part of a cell membrane is usually in contact with the interstitial fluid? a.) b.) c.) d.)

fatty acid tails hydrophobic molecules phosphate heads of phospholipids cholesterol

Focus Figure 11.2: Action Potential Part A 1. This neuron is most depolarized at +30 mV. 2. This neuron spends approximately 2.5 msec in a hyperpolarized state. 3. The ion K+ is crossing the cell's plasma membrane at 1.5 msec. 4. This cell reaches threshold at approximately 0.6 msec.

Part B: What does 0 mV on the Y-axis of an action potential tracing represent? a.) b.) c.) d.)

Ions are no longer moving across the membrane. The cell is at its resting membrane potential. The cell is both depolarized and repolarized. The cell's membrane is at equilibrium.

Part C: Similarities:   

The stimulus that triggers opening The polarity of the substances they transport across the membrane The placement of the channel protein relative to the membrane

Differences:  

The inactivation mechanism The direction of ion movement through the channel

Part D: Place the action potential events in the correct sequence. Activation gates on Na+ channels open; Na+ enters cell -> Cell depolarizes -> Inactivation gates on Na+ channels close and activation gates in K+ channels open; K+ leaves cell -> Cell repolarizes -> Activation gates on K+ channels begin to close -> Cell experiences hyperpolarization Video Tutor: Generation of an Action Potential Part A: 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? a.) b.) c.) d.)

K+ is entering the cell. Na+ is exiting the cell. K+ is exiting the cell. Na+ is entering the cell.

Part B:

What is happening to voltage-gated channels at this point in the action potential? a.) Na+ channels are opening, and K+ channels are closing. b.) Na+ channels are inactivating, and K+ channels are closing.

c.) Both Na+ and K+ channels are opening. d.) Na+ channels are inactivating, and K+ channels are opening. Part C: During what part of the action potential do voltage-gated Na+ channels begin to inactivate (their inactivation gates close)? a.) b.) c.) d.)

at the end of the repolarization phase, as the membrane potential briefly passes its resting value at the beginning of an action potential, as the membrane potential reaches threshold at the end of the depolarization phase, as the membrane potential approaches its peak value at the end of the hyperpolarization phase of an action potential, as the membrane potential returns to its resting value

Part D: The repolarization phase of the action potential, where voltage becomes more negative after the +30mV peak, is caused primarily by __________. a.) b.) c.) d.)

K+ ions entering the cell through voltage-gated channels Na+ ions transported out of the cell by the Na+-K+ pump Na+ ions leaving the cell through voltage-gated channels K+ ions leaving the cell through voltage-gated channels

Part E: During an action potential, hyperpolarization beyond (more negative to) the resting membrane potential is primarily due to __________. a.) b.) c.) d.)

Na+ diffusing through voltage-gated channels K+ ions diffusing through voltage-gated channels K+ ions diffusing through leakage channels Na+-K+ pump activity

Part F: 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? a.) b.) c.) d.)

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

Part G: Tetraethylammonium (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? a.) The action potential would fail. Once the voltage reached threshold, it would return to the resting membrane potential. b.) The membrane would depolarize as usual but then stay at that depolarized voltage (about +30 mV). c.) The membrane would depolarize and repolarize as usual, but no hyperpolarization beyond (more negative to) the resting membrane potential would occur. d.) The action potential would depolarize as usual, but the repolarization phase would take longer, causing the action potential to be more broad in time.

Video Tutor: Propagation of an Action Potential Part A: The diffusion of what ion, across the neuronal membrane, is responsible for the local currents that depolarize regions of the axon to threshold? a.) b.) c.) d.)

Na+ (sodium) Ca2+ (calcium) K+ (potassium) voltage-gated Na+ (sodium) channels

Part B: An action potential in one segment of axon causes adjacent sections of axon membrane to reach threshold through what mechanism? a.) b.) c.) d.)

Na+ ions diffusing across the membrane through leakage channels neurotransmitters causing chemically gated channels to open the generation of local currents K+ ions diffusing through voltage-gated channels

Part C: During action potential propagation in an unmyelinated axon, why doesn't the action potential suddenly "double back" and start propagating in the opposite direction? a.) The previous axonal segment is in the refractory period. b.) New action potential generation near the soma repels previously generated action potentials, causing them to always propagate away from the soma. c.) The extracellular sodium concentration is too low around the previous axonal segment for an action potential to be (re)generated. d.) Positive charges only move in one direction after they enter the cell. Part D: In a myelinated axon, how do the nodes of Ranvier differ from other segments of the same axon? a.) b.) c.) d.)

The nodes are longer segments of the axon. The nodes are less numerous. The nodes are wrapped in myelin. The nodes are more permeable to ions.

Part E: Where are action potentials regenerated as they propagate along a myelinated axon? a.) b.) c.) d.)

at the myelinated segments at every segment of the axon at the axon hillock at the nodes of Ranvier

Part F: How do action potential propagation speeds compare in myelinated and unmyelinated axons? a.) Propagation is faster in myelinated axons. b.) Propagation speeds are similar in both axon types. c.) Propagation in unmyelinated axons is faster over short distances, but propagation is faster in myelinated axons over long distances. d.) Propagation is faster in unmyelinated axons.

Part G: The node-to-node "jumping" regeneration of an action potential along a myelinated axon is called __________. a.) b.) c.) d.)

myelinated conduction continuous conduction local conduction saltatory conduction

Part H: 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? a.) b.) c.) d.)

Action potentials would propagate in both directions along the axon. The speed of action potential propagation would be faster. The speed of action potential propagation would be slower. Initial generation of action potentials would be more difficult.

Concept Map: Functional Areas of the Cerebrum Part A: Complete the Concept Map describing the major lobes, fissures, and functional areas of the cerebral cortex. Drag the appropriate labels to their respective targets.

Part B: Which of the lobes of the brain contains the gustatory cortex? a.) b.) c.) d.)

parietal temporal frontal insula

Part C: Which is NOT a function of a multimodal area of the brain? a.) becoming fearful or nervous when on a high ladder

b.) learning new concepts and relating them to previous experiences and previously learned ideas c.) maintaining body homeostasis via the interaction of the autonomic nervous system and the endocrine glands d.) recognizing someone’s face in a crowded room Part D: What brain structure separates the temporal lobe from the frontal and parietal lobes? a.) b.) c.) d.)

parieto-occipital sulcus transverse cerebral fissure central sulcus lateral sulcus

Part E: Which area of the cerebrum is responsible for understanding written or spoken words? a.) b.) c.) d.)

Broca’s area somatosensory association cortex the primary visual cortex Wernicke’s area

Concept Map: Cranial Nerves Part A

Part B: Which of the cranial nerves is responsible for regulating and balancing the effects of the sympathetic nervous system on many organs of the body? a.) b.) c.) d.)

trochlear nerves trigeminal nerves hypoglossal nerves vagus nerves

Part C: Which cranial nerve group is collectively responsible for the special senses? a.) b.) c.) d.)

cranial nerves I, II, III, and IV cranial nerves I, II, VIII, and IX cranial nerves V, VIII, IX, and XI cranial nerves II, IV, VII, and X

Part D: Which of the following symptoms would you expect a person suffering from abducens nerve paralysis to display? a.) The patient would experience partial blindness. b.) The patient would experience drooping of the eyelid, sagging of the cheek, and partial paralysis of the mouth. c.) The patient’s sense of smell would be significantly impaired. d.) The patient’s eye would have a tendency to rotate medially. Part E: The majority of cranial nerves arise from this brain region. a.) b.) c.) d.)

cerebrum brain stem cerebellum midbrain

Concept Map: Sympathetic and Parasympathetic Responses Part A:

Part B: What do the parasympathetic and sympathetic divisions have in common? a.) Most nerve fibers from both divisions share the same sites of origin. b.) Most nerve fibers from both divisions innervate many of the same effectors. c.) The ganglia from both divisions are located in or near visceral organs.

d.) The preganglionic nerve fibers in both divisions are of similar length. Part C: Most preganglionic fibers of the parasympathetic system arise from which nerve pair? a.) b.) c.) d.)

Oculomotor Glossopharyngeal Vagus Splanchnic

Part D: A normal response to sympathetic nervous system activation would most likely include the __________. a.) b.) c.) d.)

inhibition of digestive system activity decrease in heart rate increased uptake of glucose from the blood constriction of bronchioles

Part E: Which structure or organ is innervated exclusively by sympathetic fibers? a.) b.) c.) d.)

arrector pili muscles gallbladder heart iris

Concept Map: The Pathway of Light through the Eye Part A:

Part B: Which of the following structures of the eye is most responsible for absorbing light? a.) cornea b.) pupil

c.) choroid d.) lens Part C: Which eye structure is primarily responsible for making the adjustments required to focus on objects both near and far? a.) b.) c.) d.)

ciliary muscles iris cornea sclera

Part D: What is the major purpose for vitreous humor? a.) b.) c.) d.)

Circulate oxygen and nutrients to the lens Produce tears Refract the light to focus images on the retina Helps the eye maintain its shape

Part E: Cataracts typically affect which eye structure? a.) b.) c.) d.)

Cornea Ciliary muscles Retina Lens

Concept Map: The Pathway of Sound through the Ear Part A:

Part B: Which ossicle is directly connected to the tympanic membrane?

a.) b.) c.) d.)

Stapes Incus Malleus Cochlea

Part C: The semicircular canals of the bony labyrinth are responsible for detecting which type of stimulus? a.) b.) c.) d.)

low-frequency sound waves high-pitched sounds changes in head position changes in external air pressure

Part D: What is the major role of the basilar membrane? a.) b.) c.) d.)

transmit sound vibrations to the spiral organ transmit vibrations from the stapes to the oval window transmit vibrations from the outer ear to the middle ear block pathogens from entering the inner ear

Part E: What is the role of the pharyngotympanic tube? a.) b.) c.) d.)

pass sound waves from the tympanic membrane to the oval window equalize pressure between the environment and the middle ear capture sound waves and funnel them to the tympanic membrane pass sound vibrations from the nasopharynx to the tympanic membrane...