physiology exam 2

What are the functions of the meninges?

protection and they are highly vascularized

What are the functions of CSF (Cerebral Spinal Fluid)?

protection and nourishment

Is the cerebral spinal fluid the brains ECF?

no

Is the entire brain protected by the blood brain barrier?

no, parts of the hypothalamus arent

Why does the brain require a constant supply of blood?

neurons need oxygen because they cant go anaerobic and need glucose because they cant story glycogen

What is “referred pain>?”

pain from internal organ you feel on dermatome

What causes a stroke?

blood clot to the brain

What is TIA?

transient stroke, doesn’t cause permanent damage

What are a few of the functions of the brainstem?

cranial nerves emerge from here, start processing material, one of two autonomic control centers

Where are the two major autonomic control centers located in the CNS?

Brainstem and hypothalamus

What is a major function of the thalamus?

acts as a relay station for sensory info

What brain structure is the link between the nervous and endocrine system?

hypothalamus

What is the primary function of Wernicke’s area of the cortex?

language comprehension

What is the primary function of the Broca’s area of the cortex?

speaking ability

On which side of the brain do Wernicke’s and Broca’s normally develop in most people?

left side

Which side of your cortex is better at analytical tasks such as math?

left side

Where is your somatosensory cortex located?

parietal lobe

Which part of your cortex is your primary visual cortex>?

occipital

Which part of your cortex is your primary auditory cortex?

temporal

What is the basic function of your limbic system?

emotions and urges

What part of the brain functions as your internal biological clock?

SCN part of hypothalamus

How long is the normal human circadian rhythm?

a little longer than 24 hours

Is sleep an active or passive process?

active

How many periods of REM or Delta wave sleep occur during a normal night of sleep?

delta- 2, REM - 4 or 5

Why do we sleep?

repairs neurons and loads them up with glucose

What sort of drugs are often used to treat epilepsy?

GABA enhancing drugs

What neurotransmitter is released in the sympathetic chain og ganglia?

acetylcholine

What type of receptors are on the parasympathetic effector organs?

muscarinic receptors (acetylcholine)

How does ephedrine effect the autonomic nervous system?

enhances release of norepinephrine

What effect do “beta blockers” have on the autonomic nervous system?

block beta receptors at effector organ

How does atropine exert its effect on the autonomic nervous system?

inhibits, blocks receptors

What is the physiological basis of “presbyopia?”

loss of elasticity in the lens with age

WHat is the physiological basis of “myopia?”

the image is focusing in front of the retina, eyeball too long or the lens is too powerful

What causes a cataract?

denaturation of proteins in lens

What is the physiological cause of glaucoma?

too much pressure on the retina due to fluid buildup

What is the physiological importance of the optic disc?

blood vessels and nerves enter eye there

How does your brain adapt to not having photoreceptors in the optic disc?

it fills in the blindspot

What effect does light hitting the photoreceptors have on the amount of cGMP in the photoreceptors?

decrease cGMP

What is the function of the fovea of the retina?

high density of cones, area of greatest visual acuity (resolution)

What wavelengths of light are optimally detected by the rods?

green

What (physiologically) causes color blindness, and what is the most common form of color blindness?

Most common is red/green colorblindness, due to one kind of cone being nonfunctional

Rods are used for night vision

true

Cones are used for night vision

false, rods

Rods are high sensitivity low acuity

true

Rods are high acuity low sensitivity

false, cones

Only one type of photopigment is in each type of cone

true

Protanope is a person who is missing the activity of red cones

true

Protanope is a person who is missing the activity of blue cones

false, red

Protanope is a person who is missing the activity of green cones

false, red

Deuteranope is a person who is missing the activity of red cones

false, green

Deuteranope is a person who is missing the activity of green cones

true

Deuteranope is a person who is missing the activity of blue cones

false, green

Red/Green color blindness is a genetic condition and is due to a recessive gene on the Y chromosome

false, X chromsome

Red/Green color blindness is a genetic condition and is due to a recessive gene on the X chromosome

true

John Dalton was a deuteranope and was missing his green cones

true

rods are extremely bleached in bright light and are essentially non functional

true

cones are extremely bleached in bright light and are essentially non functional

false, rods

Rods adapt more slowly than cones

true

cones stop at less than a 100x increase when adapting

true

rods can increase sensitivity up to 25,000x or more within 45 minutes

true

using blue light at night helps preserve the sensitivity of the rods

false, red light

using red light at night helps preserve the sensitivity of the rods

true

part of your field of view is ________, which enhances depth perception

binocular

the pineal gland recieves sensory information from the eyes through the ________.

SCN

Pineal releases ________ during the dark

melatonin

sound waves are mechanical waves

true

the frequency range of human hearing is 20 to 20,000 cycles per second

true

the decibel scale is a logarithmic scale

true

the ear drum separates the middle and external ear

true

the ear drum separates the middle and inner ear

false, outer and middle ear

the middle ear is air filled

true

the middle ear is fluid filled

false, air filled

the eustachian tube connects the middle ear with pharynx to equalize pressure

true

The stapes attaches to “oval window” of the cochlea

true

the middle ear bones amplify the pressure wave/sound

true

the inner ear bones amplify the pressure wave/sound

false, middle ear bones

the ________ is the outermost structure of the eye

cornea

the cornea is adjustable

false, lens

the cornea is not adjustable

true

The cornea is important in helping focus light

true

the lens has an adjustable shape

true

ciliary muscle contraction results in thick lens for focusing on far objects

false, near

ciliary muscle contraction results in thick lens for focusing on near objects

true

ciliary muscle contraction results in thin lens for focusing on far objects

true

ciliary muscle contraction results in thin lens for focusing on near objects

false, far

the decrease in the ability to change the shape of the lens as you age

presbyopia

the condition when eyes can only focus on near objects

myopia

why does the image focus in front of the retina in myopia ?

the eyeball is too long or the lens system is too powerful

the condition where eyes can only focus clearly on far objects

hyperopia

why does the image focus behind the retina in hyperopia

the eyeball is too short or the cornea/lens system isnt powerful enough

_________ is an error in the curvature of the cornea

Astigmatism

the denaturation of proteins in the lens causing the lens to become cloudy or opaque

cataracts

During ________ the fluid does not drain properly through the canals of schlemm

glaucoma

_________ stimulates contraction of ciliary muscle and helps treat glaucoma

pilocarpine

the iris is composed of smooth muscle

true

pigment enhances the iris’ ability to block/control light entering the eye

true

pigment prevents the iris’ ability to block/control light entering the eye

false, enhances

Sympathetic stimulation increases pupil aperture

true

atropine is a parasympatholytic (blocks parasympathetic)

true

neurons carrying light information synapse with motor neurons in the _________.

brainstem