CH 15-18 Packets (BIO 181) Flashcards
what are the two properties of sound and how are they measured?
loudness: amplitude dB
pitch: frequency Hz
where does the external ear end?
tympanic membrane
where do we see the first and second level of amplfication of sound
1st: ossicles
2nd: oval window
where does transduction of sound energy occur?
cochlea
what are the three fluid filled compartments of the cochlea
scala vestibuli
scala media
scala tympani
in which compartments are perilymph and endolymph found?
perilymph: scala vestibuli; scala tympani
endolymph: scala media
what are the receptor cells
hair cells
what types of ion channels are located at the tips of the stereocillia of hair cells
mechanically gated
what happens when the steriocillia bend towards the tall stereocillia
channels open (depolarization) potassium enters cell
what happens when the steriocillia bend towards the short steriocillia
channels close (hyperpolarization) potassium doesnt enter cell
describes the neural pathway for sound
hair cells synapse on afferent axons of CN VIII, cochlear enters brainstem, synapse with 2nd order neuron to 3rd order neuron and travels to auditory cortex to cranial nerve 8
what are the two branches of the vestibylocochlear nerve and what is their function
- vestiular—-> equilibrium
2. cochlear—> hearing
what are the three types of cells in the olfactory epithelium and what is their function
- supporting cell—> secrete mucous
- receptor cells—>neurons that respond to odorants
- basal cells—> regeneration
what important proteins are found in mucus and what is their function
olfactory binding protiens
Describe the steps involved in olfactory signal transduction
chemicals dissolve in mucus, travel to receptor cells, trigger production of cAMP—> depolarization of receptor cells, then receptors send axons through cribiform plate to brain
what happens to the axons of the receptor cells of olfaction once they have depolarized
receptors send their axons through cribriform plate towards brain
map out the neural pathway for olfaction
olfactory nerve—> olfactory bulb—>olfactory tract to olfactory cortex (NO THALAMUS)
what are the three types of lingual papillae
curcumvallate, fungiform, filiform
how many taste buds would be found in the circumvallate papillae
100
how many tast buds would be found in the fungiform papillae
5
what is the only function of th filiform papillae
only to provide friction (NO TASTE BUDS)
what two types of cells are found in the taste buds
basal and gustatory
describe the four primary tastes and what rimary transduction mechanism is used by each
- sour: H+ binding with K+ (depolarize)
- salty: Na+(depolarize)
- bitter: nitrogen (ligands) (depolarize)
- sweet: ligands (depolarize)
describe the neural pathway for taste
receptor cells to afferent neurons via CN VII, IX, X –> CNs synapse to 2nd order neurons that project to thalamus, 3rd order neurons terminate in gustatory cortex in parietal lobe.
what does the somatic nervous system control?
voluntary control of skeletal muscles
what does the autonmic nervous system control
visceral effectors
what are the two divisions of the automonic nervous system
parasympathetic and sympathetic
describe the meaning of duel innervation
parasympathetic and sympathetic innrcate all body systems
what part of the spinal cord do the sympathetic nerves originate
thoracolumbar (t1-L2)
what regions of the spinal cord do the parasympathetic nerves originate?
sacral region and brainstem
describe the anatomy of the sympathetic nervous system
short preganglionic–> ganglia–> ling postganglionic –> effector organ
waht are the two exceptions for the general rule of anatomy of the sympathetic nervous system
collateral ganglia
suprarneal medulla
describe the anatomy of the parasympathetic nervous system
long preganglionic–> short postganglionic–> ganglia–> effector organ
where do preganglionic nerves originate in the parasympathetic nervous system
brain stem or sacral spinal cord
what cranial nerves are involved in the parasympathetic nervous system
III, VII, IX, and X
with respect to the sacral spinal nerves of the parasympathetic nervous system, what do the postganglionic nerve fibers innervate
visceral organs in the ingerior portion of the abdominopelvic cavity
what are the primary neurotransmitters involved in the automonic nervous system
acetylcholine, norpinephrine and epinephrin
describe which brances release acetylcholine versus corepinephrine in the sympathetic and parasympathetic nervous systems
1.acetylcholine–>
SYMPATHETIC: preganglionic & PARASYMPATHETIC: preganglionic and postganglionic
2.norepinephrine–>
SYMPATHETIC: postganglionic
what areas of the brain regulate autonomic function
hypothalamus, pons, medulla oblongata
give a summary of the characteristics of parasympathetic activity
rest & digest, decreased HR, BP, and metabolic rate; increased digestion and gastrointestinal activities
characteristics of sympathetic activity
fight or flight, increased HR, BP, and alertness; decreased gastrointestinal and urinary function; pupils dilate
describe what is means by tonic activity at rest
both branches are active, but at rest, parasympathetic nervous system dominates
what are the four ways in which cells can communicate
direct communication
paracrine communication
synaptic communication
endocrine communication
describe the direct communication between cells
- Exchange of ions and molecules between adjacent cells across gap junctions (cell to cell adhesion molecules)
- Occurs between two cells that are the same type
- Highly specialized and extremely fast
- Found a lot in brain and heart
describe the communication that occurs when paracrines are involved
- Chemical signals are secreted and travel a short distance to a nearby cell
- Information is transferred between different cells of a single tissue type
- Most common form of intercellular communication
describe synaptic communication
- Chemical signals (neurotransmitters) are released by a neuron into a synapse
- Target cell (postsynaptic cell) can be any type of cell
describe endocrine communication
- Endocrine cells release chemicals (hormones) into bloodstream
- Alters metabolic activities of multiple tissues and organs simultaneously
- Endocrine communication involves a hormone and it’s target cell
what are the three ways in which hormones can alter the activity of a target cell
- Stimulate synthesis of enzymes or structural proteins that are not already in the target cell
- Increase or decrease the rate of synthesis of certain enzymes or proteins
- Can turn an existing enzyme or membrane channel “on” or “off”
what are the three types of hormones based on structure alone
amino acid
peptide
what are the two ways in which hormones are transported through the body
freely
bound to transport proteins
describe the characteristics of free hormones
short lived, broken down by enzymes, taken in by liver
describe the characteristics of hormones that are bound to transport proteins
stay in blood longer (are on reserve)
what are the two types of responses that mediate the transport of chemicals in the body
intracellular
membrane bound receptors
describe the characteristics of intracellular mediated responses
used by lipid soluble hormones
what type of hormones use membrane bound receptors
not lipid soluble
what are G proteins
regulatory protein associated with plasma membrane
map out the second messenger system involving cAMP
messenger->activates G protein->alpha G protein activates adenylate cyclase->produces conversion of ATP to cAMP->activates protein cynase->phosphorlate protein-> cell response
Map out the second messenger system that uses PLC as its amplifier enzyme
messenger attachs to membrance->activates G protein->alpha G protein detaches and acivates PLC-> generates DAG and IP3->
- DAG activates protein kinase C-> phosphoralate proteins to make response in target cell
- IP3 moves into cytosol->binds to receptor on the ER-> opens channels and allows Ca into cytosol to cause a response (contraction, secretion)
five types of second messengers
cAMP IP3 cGMP DAG calcium ions (only ions that can be)
what are the two types of endocrine organs in the body and what is the difference between the two
- primary: only hormone secretion
- secondary: secrete hormones but are known for different function (eg heart)
what second messenger does the pituitary glad use
cAMP
what connects the hypothalamus to the pituitary gland
infindibulum
what are the hormones secreted by the posterior pituitary galnd and what is their function
- antidiuretic hormone: water balance and osmolarity of kidney
- oxytocin: uterine contraction and milk
what are tropic hormones
alters secretion of another hormone
describe a common tropic hormone pathway
hypothalamus–>pitutary gland–>specific endocrine gland
describe the events that occur which ultimately lead to the release of thyroid hormones, beginning with the hypothalamus
Hypothalamus releases TRH (Thyrotropin-releasing hormone)–> Anterior pituitary releases TSH (Thyroid Stimulating Hormone)–>Thyroid Gland releases Thyroid Hormone
Describe the events that occur which ultimately leads to the release of glucocoticoids, beginning with the hypothalamus
hypothalamus releases CRH–> anterior pituitary releases ACTH–> super arenal cortex releases CORTISOL
what causes the release of FSH and LH from the anterior pituitary gland
-Hypothalamus releases GnRH (Gonadotropin-releasing hormone)–>Anterior pituitary releases FSH or LH–> to Ovaries
(Estrogen, Progesterone) or Testes (Testosterone)
what causes the release of prolactin from the anterior pituitary gland
Hypothalamus releases PRF (Prolactin-releasing factors)–>Anterior pituitary releases PRL (Prolactin)–> Mammary Glands (Milk production)
describe the events that occur which ultimately leas to the release of somatomedins
Hypothalamus releases GH-RH (Growth hormone-releasing hormone)—>Anterior pituitary releases GH (Growth Hormone) –> Liver releases Somatomedins (insulin-like growth factors)
what are the three mechanisms that control tropic hormone release
neural input, hormonal input, and circadian rhythm
what two types of thyroid hormones and give their function
T3 and T4 both regulate metabolism
what is the funciton of calcitonin
to regulate calcium
what is the precursor to the thyroid hormones and where is it found
thyroid globulin molecule
describe the chain of events that occur with the synthesis and secretion of thyroid hormones
- Thyroglobulin (TG) = protein located in colloid
- Precursor for thyroid hormones
- Contains tyrosine residues
- Iodide ions = I- = absorbed from the diet
- Actively transported from blood into colloid
- Added to thyroglobulin to form T3 and T4 thyroid hormones
- Once T3 and T4 hormones are made, they can remain in the colloid (bound to TG molecule) for up to three months
- When TSH arrives via the bloodstream, it binds to it’s receptor on the membrane to activate cAMP (step 4)
- The cascade of events of this second messenger system ultimately phosphorylates a follicular protein (step 4)
- This triggers Follicular cell to take in the TG (with T3 and T4 attached to it) via phagocytosis (step 5)
- Phagosome containing TG fuses with a lysosome and allows the separation and breakdown of TG and the diffusion of T3 and T4 into the bloodstream (step 6 and 7)
how long can T3 and T4 remain in the colloid
up to three months
what are the functions of thyroid hormones
regulate metabolism
what hormones is secreted by the parathyroid gland and what is its function
parathyroid hormone: regulates calcium levels
all hormones secreted by the adrenal cortex are referred to as what
adrenocorticoids
what are the three hormones secreted by the adrenal cortex
mineralocorticoids, glucocortocoids, sex hormone
what is the function of mineralocorticoids
regulates Na and K levels
what is the function of glucocorticoids
regulates metabolism and mediates stress response
all hormones secreted by the adrenal medulla are known as what
catecholamines
name the three types of catecholamines and what cells secrete them in the adrenal medulla
epinephrine, norepinephrine, dopamine
what hormone is secretes by the pineal gland and what is its function
melatonin–> circadian rhythm
what are the four types of cells in the endocrine pancreas and what hormones do they secrete
- Delta cells produce somatostatin
- F cells secrete pancreatic polypeptide (PP)
- Alpha cells produce glucagon
- Beta cells produce insulin
what is the function of pancreatic polypeptide
Functions in regulating production of pancreatic enzyme and the rate of food absorption
what is the function of somatostatin
similar to GH-IH (growth hormone-inhibiting hormone) regulates digestion & absorption as well as suppresses insulin and glucagon release
what are the funcitons of insulin and glucogon
regulate metabolism and blood glucose levels
what happens when blood glocose levels rise above normal?
- Beta cells secrete insulin
- Increases glucose uptake by cells
- Promotes glucose use for energy
what happens when blood glocose levels fall blow normal?
- Alpha cells secrete glucagon
- Stimulates glycogen breakdown
- Stimulates glucose release by liver
name five types of secondary endocrine gland
- Intestines (digestive system)
- Kidneys (urinary system)
- Heart (cardiovascular system)
- Thymus (lymphoid system and immunity)
- Gonads (reproductive system)
what is the function of the hormones secreted by the intestines
aid in digestion
what hormones are secreted by the kidney and what is their function
- erythroprotien: stimulates red blood cell production
2. calcitriol : regulate blood calcium level
what hormones are secreted by the heard and what is their function
ANP and BNP
both reduce the blood volume and pressure
what hormone is secreted by the thymus gland and what is its function
thymosin: maintain normal immune defense by regulating T cell function
what hormones are secreted by the gonads in males and females
- males: androgens
- females: estrogens
what are the four ways in which two or more hormones can have an affect when they are released simultaneously
- Antagonistic (opposing) effects
- Synergistic (additive) effects
- Permissive effects: one hormone is necessary for another to produce effect
- Integrative effects: hormones produce different but complementary results
name the hormones that are important for growth
growth hormone, thyroid hormone, insulin, parathyroid hormone
describe the effects of growth hormone in children and adults
- In children it Supports muscular and skeletal development
* In adults it Maintains normal blood glucose concentrations and Mobilizes lipid reserves
what is the affect of thyroid hormones during fetal development
develops nervous system
what is the alarm phase and what hormones dominate this phase of stress?
immediate response to stress; epinephrine and norepinephrine
what is the resistance phase and what is the primary hormone mediating this phase of stress
Occurs when stress lasts for more than a few hours
•Glucocorticoids (Cortisol)
what is the exhaustion phase and what can happen if the stress is not corrected
multiple organ failure and death if its not corrected
draw a concept map of the nervous system showing all components
CNS
PNS–>
afferent
efferent
what are the two subdivisions of the PNS
afferent and efferent
what are the functions of sensory receptors
sensory, interpretation, processing, transduction
define sensory receptors
specialized nerve ending or cells that detect a sensory stimulus
define transduction
the process by which the stimulus energy is converted into electrical energy
what is adaptation
reduction in sensitivity to a constant stimulus
what are slow and fast adapting receptors
- slow: active for duration of stimulus (eg root hair plexus, meisner corpuscles,laminated corpuscles)
- fast: only active at the onset and offset of stimulus (riffini corpusles, merkles discs, free nerve endings)
how does the brain code for stimulus type
specific pathway
how does the brain code for stimulus intensity and define each mechanism
- frequency coding: more action potentials
- recruitment: more receptors activated
how does the brain code for stimulus location and acuity
size and overlap
define receptive field
area of the body that is monitored or innervated yt a receptor
what body part(s) have the greatest tactile acuity
lips
what is the difference between the general and special senses
- general: somastetic sensation involving touch, pain, propriception
- special: vision, taste, smell, auditory, equilibrium
what are the four types of somatosensory receptors
nocieceptors
thermoreceptors
chemoreceptors
mechanoreceptors
what are nociceptors
pain receptors
what two types of pain do we perceive
- fast prickling (we can localize)
- slow, burning, aching (we can can’t localize)
what type of pain is carried by myelinated type A fibers
fast, pricking pain
what type of pain is carried by unmyelinated type C fibers
slow, aching, burning pain
where are thermoreceptors found
dermis, skeletal muscles, liver, hypothalamus
what are mechanoreceptors and what type of ion channels do they possess
- sensitive to stimuli that distort their plasma
- mechanically gated ion channels
what are the three types of mechanoreceptors
baroreceptors
proprioceptors
tactile receptor
what do baroreceptors detect
pressure changes in walls of blood vessels and in portions of the digestive, reproductive, and urinary tracts
what do proprioceptors monitor
position of joints, tension in tendons and ligaments, and state of muscle contraction
what are the characteristics of the tactile receptors that detect fine touch and pressure
extremely sensitive, small receptive fields, give detailed information on source of stimulation
what are the characteristics of the tactile receptors that detect CRUDE touch and pressure
lare receptor fields, poor localization, give little information on stimulation
what are the characteristics of free nerve endings
detect pain, located between epidermal cells, tonic receptors, have small receptive fields, slow adapting
what are the characteristics of Merkel discs
detect fine touch and pressure, extremely sensitive tonic receptors, have small receptive fields, slow adapting
what are the characteristics of Ruffini Corpuscles
detect crude pressure and distortion, deep in dermis, slow adapting
what are the characteristics of Root hair plexus
detect hair movement across body surfaces; rapidly adapting
what are the characteristics of Meissner corpuscles
detect fine touch, pressure, and low frequency vibrations, fairly large, rapidly adapting, in eyelids, lips and fingertips
what are the characteristics of Pacinian corpuscles
detect seep pressure, most sensitive to pulsing or high frequency stimuli, rapidly adapting
describe the sensory pathway from the receptors to the cortex
first, second, and third
what sensations are carried by the posterior column pathway and where does that information cross over
highly localized (fine) touch, pressure, vibration, and proprioception crosses over at the brainstem
what sensations are carried by the spinothalamic pathway and where does that information cross over
conscious sensations of poorly localized (crude) touch, pressure, pain, and temperature.
crosses over immediately at the spinal cord
what type of information is carried by the spinocerrebellar pathway and where does this information terminate
carries proprioceptive information about position of skeletal muscles, tendons and joints
terminates in the cerebellum
what three pathways are included in the descending Pyramidal system
anterior corticospinal pathway
lateral corticospinal pathway
corticobulbar pathway
what type of information is carried by the pyramidal system and where does this information terminate
voluntary movement of skeletal muscles
what type of information is carried by the descending extrapyramindal tracts
involuntary
what are the three layers that make up the eye
fibrous tunic
vascular tunic
neural tunic
waht makes up the fibrous tunic
sclera and cornea
what makes up the vascular tunic
choriod
ciliary body
iris
define refraction
bending of light as it passes through
define accommodation
curvature of lens can change as needed
describe how we focus on near objects
lens increases curvature, lens becomes more curved, and refractive index increases
describe how we focus on distant objects
lens decreases curvature, lens becomes more flattened and refractive index decreases
discuss the parasympathetic innervation of the eye and how it affects the shape of the lens
constrict inner circular muscles (less light enters the eye)
what are the characteristics of myopia and how is it corrected
lens is too strong and converges light too much, mage focused in front of retina
concave lens diverges more light
what are the characteristics of hyperopia and how is it corrected
lens is too wear and doesn’t converge light enough, image is focused behind retina
convex lins converges more light
describe how the nervous system control the amount of light entering the eye
- parasympathetic–> less light enter d(inner muscles)
- sympathetic–> more light enter eye (radial, outer muscle)
what is the pathway of information within the retina
pigmented epithelium–>photo receptor layer–>bipolar cell layer–> ganglion cell layer
define fovea
central point of the retina; packed with cones (NO RODS), point of highest visual acuity
define optic disc
circular region just medial to fovea where optic dic originates
describe the process of phototransduction in the darkness and in the presence of light
- dark=photoreceptor depolarization–> increase in neurotransmitter release
- light= photoreceptor hyper polarization–> decrease in neurotransmitter release
what are the first cells in the visual pathway that generate action potentials
ganglion cells
describe the neural pathway of visual information from the retina to the primary visual cortex
retina–> lateral geniculate nucleus—> primary visual cortex
