Zool 2200 Final 2

The falling or repolarization phase of an action potential is due to:

(b) and (c) - opening of voltage gated potassium channels. - closing of voltage gated sodium channels.

The brain uses 20% of the oxygen we take in during rest because: - it is continuously active - it cannot do anaerobic glycolysis - it can only aerobically metabolize glucose - all of the above

all of the above

Which of the following statements about sensory coding is TRUE? - Coding for a stimulus type is maintained from receptor to cortex. - The intensity of stimulus is coded for by the frequency of the action potential. - The location of the stimulus is coded for by the receptive field activated. - The type of stimulus is coded for by the specific pathway activated. - All of the above are true.

all of the above are true

Which is characteristic of fast pain?

impulses carried along myelinated fibers

Which of the following physiological responses would be associated with elevated sympathetic nervous system activity?

increased contractile force of the heart

If a cell became permeable to sodium:

the cell would depolarize.

What type of glial cell myelinate efferent and afferent neurons?

Schwann cells

Olfactory receptors: - are specialized endings on afferent neurons. - detect thousands of types of odorants. - only detect chemicals that are volatile. - send excitatory messages to the olfactory bulb when a specific odorant binds to a receptor. - all of the above

all of the above

The absolute refractory period of an action potential: incorrect causes the unidirectional flow of action potentials. - spans all of the depolarization phase and most of the repolarization phase. - is the period in which a second action cannot be fired. - is the period in which the sodium channels are either open or inactivated. - all of the above.

all of the above

Electrical synapses: - are formed when two neurons are connected by gap junctions. - are much less common than chemical synapses. - transfer messages faster than chemical synapses. - are bidirectional. - are all of the above.

are all of the above.

The _______ is the first place on a neuron that fires an action potential.

axon hillock

The ______ is a region of the cerebrum that selects and maintains purposeful motor activity while suppressing useless or unwanted patterns of movement. This area of the brain is damaged in Parkinson's disease.

basal nuclei

In order for ions like sodium, potassium and calcium to move across the capillary endothelial cells of the blood-brain barrier, they must ________.

be transported across endothelial cells

The ________ is the region of the brain that controls heart and blood vessel function, respiration, and many digestive functions.

brainstem

The ________ is the region of the brain involved in the control of subconscious coordination of learned motor tasks like walking.

cerebellum

Which types of receptors would the body use to detect overall solute levels in blood?

chemoreceptors and osmoreceptors

At an excitatory synapse, neurotransmitter released from the presynaptic neuron may cause the __________.

depolarization of the postsynaptic cell

Whether the hair cells in the semicircular canal are depolarized or hyperpolarized is dependent upon the ________.

direction the stereocilia on the hair cells are bent

Unmyelinated axons:

have action potentials spread down the axon by contiguous conduction.

Cones:

have high acuity

The ________ is a region of the diencephalon that provides an important link between the endocrine and nervous system.

hypothalmus

he resting membrane potential of cells:

is maintained by the sodium potassium pump.

The opening of which channel would cause an inhibitory graded potential?

ligand gated potassium channel

The ________ is a region of the diencephalon that filters and refines sensory information, allowing us to direct our attention to specific external stimuli.

limbic system

Which of the following characteristics is NOT a specialization of the right side of the cerebrum in most individuals? - artistic qualities - creativity - logic - musical - spatial perception

logic

What type of sensory receptor detects sound waves in the cochlea?

mecahnoreceptor

Sensory receptors that respond to tissue-damaging stimuli or stimuli that have the potential to damage tissue are called ________.

nociceptors

The ________ contains the visual cortex because visual information is processed there.

occipital lobe

The rising or depolarization phase of an action potential is due to:

opening of voltage gated sodium channels.

The _______ localizes the source of sensory input from the skin and perceives the level of intensity of the stimulus.

primary somatosensory cortex

When we enter a dark room, the retinal and opsin molecules within the ________ must first ________ before low light levels can be detected.

rods : associate

Which taste is perceived when sodium ions in food or drink enter through channels on taste receptor cells?

salty

The sympathetic nervous system has ________ preganglionic neurons and _______ postganglionic neurons.

short : long

When the ciliary muscles of the eye are contracted, the zonular fibers are _____ and the lens is relatively ________, allowing the eye to focus on objects that are ________.

slack: round : close

he knee jerk reflex is an example of a(n) ______ reflex.

stretch

he radial muscles of the iris are innervated by the ________ nervous system and their contraction causes pupillary ________.

sympathetic : dilation

Pain signals from visceral receptors are 'referred' to the body surface by ________.

the convergence of visceral and somatic afferent neurons on the same second-order neurons

Amplitude or loudness of sound is coded for by ________.

the degree of deflection of the stereocilia on the hair cells stimulated.

During the relative refractory period it is harder to fire another action potential because _________.

voltage gated potassium channels are open and the membrane is hyperpolarized.

Order the following events that occur at the synapse from first to last. 1 - calcium triggers exocytosis of neurotransmitter from the presynaptic neuron 2 - neurotransmitter diffuses across the synapse and binds to a receptor on the postsynaptic cell 3 - an action potential reaches the axon terminal of the presynaptic cell 4 - neurotransmitter is removed from the synapse to terminate the response 5 - voltage gated calcium channels open on the axon terminal of the presynaptic cell 6 - the postsynaptic cell responds

3,5,1,2,6,4

he steps of synaptic transmission at the neuromuscular junction are listed below, out of order. Choose the correct order. 1 - Acetylcholine binds to receptors on the motor end plate. 2 - Acetylcholine is released by exocytosis from the motor neuron. 3 - An action potential is produced on the muscle fibers sarcolemma. 4 - Voltage-gated calcium channels on the motor neurons plasma membrane open. 5 - An action potential arrives at the motor neurons axon terminal.

54213

Which of the following is the correct order of the meninges, from bone to neural tissue?

Arachnoid mater : pia mater : dura mater

Which of the following statements concerning receptors is correct? - Receptor adaptation results from nerve fatigue. - Receptors are part of efferent neurons. - The larger the receptor potential, the greater the amplitude of action potentials initiated in the afferent neuron. -Tonic receptors often exhibit an off-response. - Tonic receptors are important in situations where maintained information about a stimulus is valuable.

Tonic receptors are important in situations where maintained information about a stimulus is valuable.

Graded potentials: - can sum temporally or spatially. - can be excitatory. - can be inhibitory - cause action potentials - all of the above.

all of the above

A reading disability like dislexia is due to a problem in _________ that governs language comprehension.

Wernicke's area

With respect to their innervation, individual skeletal muscle fibers (cells) are innervated by:

a single motor neuron

Parasympathetic preganglionic neurons release the neurotransmitter ________; sympathetic postganglionic neurons release the neurotransmitter ________.

acetylcholine : norepinephrine

Which of the following endocrine glands is innervated by sympathetic preganglionic neurons and releases epinephrine and norepinephrine into the bloodstream when stimulated?

adrenal medulla

Sensory neurons often act as the ___________ in basic reflexes.

afferent pathway