Phys test 2

What photosensitive cells within the retina distinguish different spectral components of light

cones

Immune defense cells of the CNS

microglia

What is nearsightedness called

myopia

What is the photopigment in rods

rhodopsin

Photoreceptors that are responsible for night vision are called

rods

What does the PNS consist of?

trunk and limbs (also ANS and SNS)

Where is the optic chasm located

underneath the hypothalamus

What is the fastest transmission rate of A-delta fibers

up to 30m/sec

Night blindness is a result of a deficiency in what nutrient

vitamin A

What kind of tactile receptor is stimulated by light, sustained touch

Merkel's discs

Main neurotransmitters involved with pathways for emotions and behavior

Norepinephrine, dopamine, serotonin

Cells that are the main glue of the CNS, aid in establishing the BBB

astrocytes

How many pairs of cranial nerves are there?

12!!!!!!

How many tactile mechanoreceptors are estimated to be in a typical fingertip

17,000

Photoreceptors in the eye are sensitive to wavelengths between

400-700 nanometers

What is the estimated number of neurons in the brain

86 billion

What nerve fibers constitute the fast pain pathway

A-delta fibers

What part of the brain is associated with language understanding and speech

Broca's area

Impulses from polymodal nociceptors that respond to chemicals released into the ECF from damaged tissues are carried by small, unmyelinated fibers

C

What nerve fibers constitute the slow pain pathway

C fibers

The spinal cord is classified within which part of the nervous system?

Central nervous system

T/F Perception is our unconscious interpretation of the external world as created by the brain from a pattern of nerve impulses delivered to it from mechanoreceptors

False CONSCIOUS interpretation

T/f the afferent division carries information away from the CNS

False Efferent division

T/F Information lost from short term memory is temporarily forgotten, but information in long term storage is often permanently forgotten

False. Short term memory- permanently forgotten Long term memory- temporarily forgotten

What area of the brain is associated with language comprehension

Wernicke's area

Some receptors diminish the extent of their depolarization despite sustained stimulus strength, a phenomenon known as

adaptation

What receptors of the brain are blocked by caffeine

adenosine receptors

Three functional classes of neurons in the nervous system

afferent, efferent, interneurons

The aqueous humor, which carries nutrients between the cornea and lens, is located where

anterior cavity

What is the function of the cerebellum

balance and movement coordination

Depth perception relies on what kind of field of vision

binocular

The strength of the lens depends on its shape, which in turn is regulated by what muscle

ciliary muscle

What is the anterior, transparent outer layer of the eye through which light rays pass (focusing)

cornea

Neural bridge that connects the two cerebral hemispheres

corpus callosum

During pre cortical processing of sensory input, some features of stimuli are accentuated and others are suppressed through

cortical damping

Nociceptors are sensitive to

damage (pain)

Each spinal nerve carries afferent sensory fibers from a particular region on the body surface called a

dermatome

What painkilling mood enhancing compounds are released during prolonged exercise such as jogging

endorphins

These CNS cells line the internal cavities and circulate CSF

ependymal cells

T/F If the aqueous humor is not drained as rapidly as it forms, pressure builds up within the eye and creates a condition called cataracts

false glaucoma

T/F The two structures most important in the eye's refractive abilities are the iris and pupil

false lens and cornea

T/F The smaller the receptive field is in a region, the less its acuity or discriminative ability

false smaller receptive field= greater acuity

T/F Most of the eyeball is covered by a tough outer layer of connective tissue, the macula, which forms the visible white part of the eye

false. sclera

The limbic system includes the amygdala, which is important for processing what emotions

fear and anxiety

The optical center of the retina and the region of greatest acuity is called the

fovea

Which lobe of the brain is located most ventrally (front)

frontal

About 90% of the cells in the CNS are

glial cells

What ligand binds to the AMPA receptors and NMDA receptors of the postsynaptic neuron

glutamate

What are two forms of short-term memory

habituation and sensitization

What part of the brain plays an especially important role in declarative memories

hippocampus

What part of the limbic system controls the increase of HR and respiratory rate, elevation of BP, and diversion of blood to skeletal muscles

hippocampus

Photoreceptors are ____ by their adequate stimulus

hyperpolarized

What are of the brain is most involved in directly regulating the internal environment (homeostasis)

hypothalamus

What gland produces tears

lacrimal gland

The storage capacity of long term memory bank is ______ than the capacity of short term memory

larger

Besides receptor density, a second factor influencing acuity is

lateral inhibition

The pea sized area immediately surrounding the fovea with a high concentration of cones and fairly high acuity is called

macula lutea

What condition is typically referred to as "donut vision"

macular degeneration

What are the nourishing membranes that lie between the bony covering of the CNS and nervous tissue

meninges

The primary visual cortex is in what lobe of the brain

occipital

What lobe of the brain is situated most posteriorly

occipital

These cells form myelin in the CNS

oligodendrocytes

Which lobe of the brain is located most superiorly

parietal

What are rapidly adapting receptors called

phasic

What components make up the brain stem

pons, medula, midbrain

The vitreous humor, which maintains the spherical shape of the eye, is located where

posterior cavity

What condition occurs when the lens of the eye loses elasticity and can no longer assume the spherical shape required to accommodate for near vision

presbyopia

What compound greatly sensitized all nociceptors to noxious stimuli

prostaglandins

Storing long term memories involves the synthesis of what new compounds

proteins

What colors do specialized photoreceptors detect directly

red, blue, green

Within the eye, what innermost pigment layer contains nervous tissue

retina

What is the eye's tough, outer white layer of connective tissue

sclera

What is the function of the thalamus

sensory and relay station

The cerebral cortex is organized into how many well-defined layers

six

The withdrawal reflex is an example of what reflex category

somatic reflex

Which lobe of the brain is located laterally

temporal

Define proprioreception

the awareness of body position

What happen when the radial muscle of the eye contracts or shortens

the size of the pupil increases (dilates)

What are slowly adapting receptors called

tonic

T/F Only the interstitial fluid (not the blood) comes into direct contact with neurons and glial cells in the brain

true

T/F Sensitization is defined as increased responsiveness to mild stimuli following a strong or noxious stimulus

true

T/F The amount of light entering the eye is controlled by the iris

true

T/F The cortex has a default mode network that is most active when the mind wanders

true

T/F The larger posterior cavity between the lens and retina contains a clear, jellylike substance, vitreous humor

true

T/F The prefrontal cortex is largely responsible for the so-called executive functions

true

T/F The primary areas of cortical specialization for language are Broca's and Wernicke's area

true

T/F The vestibulocerebellum is important for maintaining balance and controls eye movements

true

T/F Tonic receptors do not adapt or adapt slowly

true