Human Physiology Exam 2 Questions (Chapters 5 & 6)

what photosensitive cells within the retina distinguish different spectral components of light?

cones

What are the immune defense cells of the CNS called?

microglia

what are the main neurotransmitters involved with pathways for emotions and behavior?

norepinephrine, dopamine and serotonin

what is the photopigment in rods?

rhodopsin

photoreceptors called ______ are responsible for night vision

rods

True or False "the larger posterior cavity between the lens and the retina contains a clear, jellylike substance, the vitreous humor"

true

True or False "the prefrontal cortex is largely responsible for the so-called 'executive' functions"

true

True or False "the primary areas of cortical specialization for language are Broca's area and Wernicke's area"

true

True or False "the vesibulocerebellum is important for maintaining balance and controls eye movements"

true

True or False "tonic receptors do not adapt or adapt slowly"

true

where is the optic chiasm located?

underneath the hypothalamus

what is the fastest transmission rate of A-delta fibers?

up to 30 m/sec

night blindness is a result of a deficiency of what nutrient?

vitamin A

what kind of tactile receptor is stimulated by light, sustained touch?

Merkel's discs

what are two forms of short-term memory?

habituation and sensitization

how many pairs of cranial nerves are there?

12

how many tactile mechanoreceptors are estimated to be in a typical fingertip?

17,000

the photoreceptors in the eye are sensitive to wavelengths between _________

400 and 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

impulses from polymodal nociceptors that respond to chemicals released into the ECF from damaged tissue are carried by small, unmyelinated ______ fibers

C fibers

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 called ______

adaptation

what receptors in the brain are blocked by caffeine?

adenosine receptors

What are the three functional classes of neurons in the nervous system?

afferent, efferent, and interneurons

depth perception relies on what kind of field of vision?

binocular

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

central nervous system

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

ciliary muscle

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

meninges

What is the name of the neural bridge connecting the two cerebral hemisphere of the brain?

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

each spinal nerve carries afferent sensory fibers from a particular region on the body surface called a(n):

dermatome

what painkilling and mood enhancing compounds are released during prolonged exercise, such as jogging?

endorphins

True or False "information lost from short-term memory is temporary forgotten, but information in long-term storage is often forgotten permanently"

false

True or False "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

True or False "the smaller the receptive field is in a region, the less its acuity or discriminative ability"

false

True or False "the two structures most important in the eye's refractive ability are the iris and the pupil"

false

True or False "the afferent division carries information away from the CNS"

false carries to CNS

True or False "if the aqueous humor is not drained as rapidly as it forms, pressure builds within the eye and creates a condition called cataracts"

false glaucoma

True or False "most of the eyeball is covered by a tough outer later 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 ________ is in the optical center of the retina and the region with greatest acuity

fovea centralis

About 90% of the cells within the CNS are ________

glial cells

what ligand binds to the AMPA receptors and NMDA receptors of the postsynaptic neuron?

glutamate

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

hippocampus

what part of the limbic system controls the increase of heart rate and respiratory rate, elevation of blood pressure, and diversion of blood to skeletal muscles?

hippocampus

photoreceptors are _______ by their adequate stimulus

hyperpolarized

what area of the brain is most involved in directly regulated the internal environment (homeostasis)?

hypothalamus

what gland produces tears?

lacrimal gland

the storage capacity of the long-term memory bank is __________ than the capacity of short-term memory

larger

besides receptor density, a second factor influencing acuity is _________ inhibition

lateral

the pea-sized area immediately surrounding the fovea is called the _______ which has a high concentration of cones and fairly high acuity

macula lutea

what components make up the brain stem?

medulla, pons and midbrain

the primary visual cortex is situated in the _______ lobe of the brain

occipital

what lobe of the brain is situated most posteriorly (back of the head)?

occipital

what are rapidly adapting receptors called?

phasic

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

__________ is the awareness of body position

proprioception

what compound greatly sensitizes all nociceptors to noxious stimuli?

prostaglandins

storing long-term memories involves the synthesis of what new compounds?

proteins

what colors do special photoreceptors detect directly?

red, green, and blue

within the eye, what innermost pigment layer contains nervous tissue?

retina

based on varying distributions of several distinctive cell types, the cerebral cortex is organized into how many well-defined layers?

six

the withdrawal reflex is an example of what reflex category?

somatic reflex

what happens when the radial muscle of the eye contracts or shortens?

the size of the pupil increases

True or False "only the interstitial fluid (not the blood) comes into direct contact with the neurons and glial cells in the brain"

true

True or False "sensitization is defined as increased responsiveness to mild stimuli following a strong or noxious stimulus"

true

True or False "the amount of light entering the eye is controlled by the iris"

true

True or False "the cortex has a default mode network that is most active when the mind wanders"

true