Exam 2 - Chapter 10

Describe the sequence of signal transduction in the retina...

1. Light passes through the lens and strikes the retina 2. Rods & cones become excited and phototransduction occurs 3. Glutamate is released onto the bipolar cells. 4. Signal is conducted to the ganglion cells. 5. Optic nerve delivers signal to the brain.

Which primary-to-secondary neuron ratio would allow for the greatest receptive field sensitivity?

1:1

The ability to distinguish different pitches (frequencies) of sound results from which of the following?

Changing sensitivity to pitch along the length of the basilar membrane

A layer containing an abundance of blood vessels.

Choroid

The _____ are a group of photoreceptor cells that function best for color vision.

Cones

What type of neural circuit is represented by the sensory neurons of the retina?

Convergent

The CNS must distinguish four properties of a stimulus. These properties include location, intensity, modality, and which other property?

Duration

Which of the following would occur if you were to surgically remove the pigmented epithelium of the retina?

Entering light would be scattered across the retina and it would be difficult to obtain a sharp image.

The _____ is an area that contains only cones and serves as the eye's point of sharpest vision.

Fovea

A receptor potential is a type of ________ potential.

Graded

What is the significance of the neuronal circuit setup of the retina?

It allows for a single multipolar neuron to process the signal from hundreds of different photoreceptors.

A neuron that has responded to a stimulus causes decreased activity in neighboring neurons in which process?

Lateral inhibition

Which of the following types of receptors are involved in hearing?

Mechanoreceptors

Which receptors are the hair cells of the ear?

Mechanoreceptors

What sensory pathway is the only one not to synapse in the thalamus?

Olfaction

The extension of the forebrain that receives odor input from the nose is the ________.

Olfactory Bulb

A convergence of axons from the retina that leave the eye through the optic disc.

Optic Nerve

Baroreceptors in the aortic arch and carotid bodies are mechanoreceptors that respond to the stretch that occurs in these arterial walls with changes in blood pressure. If pressure changes rapidly, the baroreceptors initiate a feedback mechanism that reduces blood pressure; however, if pressure changes slowly, as in developing hypertension, the receptors do not respond. Given this information, the baroreceptors are most likely which type of receptor?

Phasic Receptors

A layer that functions to absorb excess light.

Pigment epithelium

Which of the following structures is/are found in the retina?

Pigment epithelium, ganglion cells, amacrine cells, photoreceptors, horizontal cells, bipolar cells.

A pigmented layer and layers of neuronal cells that together serve for phototransduction.

Retina

The ______ are a group of photoreceptor cells that function best in low light.

Rods

A layer that contains collagen fibers, forming a thick fibrous protective layer around the eye.

Sclera

Which structures contain receptors that detect rotation of the head?

Semicircular canals

Where do all tertiary somatic sensory neurons terminate?

Somatosensory cortex

Which of the following correctly describes how a photoreceptor responds to light?

The receptor hyperpolarizes, decreasing the amount of neurotransmitter it releases.

What mechanism causes hair cell depolarization as stereocilia bend in response to sound waves?

Tip links open ion channels, which causes membrane depolarization.

What specific area of a neuron could be considered the integrator?

Trigger zone