Physiology II Exam 1 Study Questions

Are there strong and weak action potentials within the body?

False

Which classification system includes both sensory and motor fiber classifications?

Erlanger's

What is a rapidly adapting mechanoreceptor essential for the detection of vibration?

Pacinian corpuscle

What triggers a sensory receptor to be stimulated?

Increase in membrane permeability to Na+

Which Erlanger's type fibers carry vibratory sensation?

A-beta

What is defined as the conversion of an environmental stimulus into an electrical impulse?

Sensory transduction

What are the fastest fibers classified in Erlanger's system?

A-alpha

Does a receptor responding to a weak stimulus relay a high frequency of action potentials?

False

Which of the following is NOT a property of all somatic sensory receptors?

They are all bipolar

Do nociceptors respond to extreme intensity of pressure, temperatures, or chemicals?

False

What are the thinnest fibers classified by Lloyd's?

Type IV fibers

Which ascending tract carries pain signals from the lower extremities?

Lateral spinothalamic

Does a neuron with a receptor in the foot synapse on the 2nd order neuron until it reaches the brain stem?

True

Are the fibers that make up the dorsal columns mostly slow B & C fibers?

False

Which statement is NOT correct regarding sensory innervation of joints?

Joints are lightly innervated with proprioceptors

Which ascending tract carries vibratory sensation from the feet?

Gracilis of dorsal columns

Do fibers from the lateral spinothalamic tract decussate shortly after originating in the dorsal gray horn?

True

Which ascending pathway allows for subconscious processing of proprioception?

Dorsal spinocerebellar

Where is the primary somatosensory cortex located?

Just posterior to the central sulcus

What carries efferent signals from the ventral horn of the spinal cord to the intrafusal muscle fibers?

A-gamma fibers

Which pathway is utilized when nociceptors are stimulated by chemical signals?

Paleo lateral spinothalamic

What signal is produced in the body when a sprained ankle is inflamed and swollen?

Nociceptive chemical stimuli

Which of the following is NOT one of the 3 wavelengths of light that cones are differentiated by?

Yellow

Which structure does light NOT pass through on its way to the retina?

Iris

How many layers of retinal cells must light pass through to reach the pigmented cells?

5

Which primary taste is due to chemosensitive receptor cells sensitive to H+ ions?

Sour

What occurs during visual transduction when light strikes a photoreceptor?

The photoreceptor hyperpolarizes, leading it to stop releasing inhibitory neurotransmitter at the synapse with a bipolar cell

During transduction of equilibrium, how must stereocilia bend for depolarization to occur?

Toward the kinocilium

What is the normal hearing range for healthy adults?

20 - 20,000 Hz

Which photoreceptor is most sensitive to low levels of light?

Rods

Which structure houses the site of auditory transduction, the organ of corti?

Scala media

Which photoreceptor responds to light in 3 different wavelength ranges?

Cones

Does olfactory transduction rely on 5 different receptor proteins?

False

What accounts for the ability to process sounds at varying pitches/frequencies?

Basilar membrane

Where is angular/dynamic equilibrium transduced?

Semicircular canals

Resting membrane potential is_______

-70mV

The sodium potassium pump transports________

3 Na+ out and 2 K+ in and Active Mechanism