QUIZ 5 Flashcards
(122 cards)
1
Q
visceral efferent: autonomic
A
- sympathetic
- parasympathetic
2
Q
somatic vs autonomic: type of control
A
- somatic- voluntary (conscious)
- autonomic- involuntary (unconscious)
- you can control the autonomic by some extent through meditation (raise heart beat)
3
Q
somatic vs autonomic: type of effector organ that it innervations
A
- somatic- skeletal muscle
- autonomic (visceral efferent)- smooth, cardiac glandular
4
Q
somatic vs autonomic: number of neurons from CNS to effector organ
A
- somatic- only one neuron (myelinated) runs out of the CNS from the spinal cord directly to synapse on the effector organ
- autonomic- two -> preganglionic (myelinated) and postganglionic (unmyelinated)
5
Q
parasympathetic
A
- peripheral portion of a parasympathetic -> preganglionic neuron is longer
- preganglionic neuron long
- postganglionic neuron short
- ganglion closer to target organ (in the wall of the target organ)
- rest and digest
- preganglionic secretes ACh
- postganglionic secrete ACh
- outflow cranially (4 cranial nerves) and caudal/sacral (S2,S3,S4)
- preganglionic cell bodies (brainstem or S2-S4 lateral horns)
- ganglion- terminal ganglia and intramural ganglia
- pelvic splanchnic nerve
6
Q
sympathetic
A
- preganglionic neuron short
- postganglionic neuron long
- ganglion closer to CNS
- fright, flight, fight
- preganglionic secretes ACh
- postganglionic secrete norepinephrine
- outflow from the CNS from the spinal cord (T1-L2)
- preganglionic cell bodies- T1=L2 (lateral horn)
- ganglion- paravertebral, prevertebral (celiac, superior mesenteric, inferior mesenteric)
- sympathetic chain (trunk)
- sympathetic splanchnic nerve (pass through the sympathetic chain to synapse at the prevertebral ganglion)
- sympathetic organ nerve
7
Q
bright light on retina
A
- picked up by CNS
- brain nucleus
- synapse at ciliary ganglion
- ACh release
- received by nicitonic receptors
- pupil contriction
8
Q
parasympathetic innervation
A
-cranial nerves CNIII ,CN VII, CN IX , CNX and S2-S4
9
Q
parasympathetic ganglia
A
- terminal ganglion- ganglion located near the target effector
- intramural ganglion- ganglion located in the wall of the target organ (pelvic sphlancnic nerves or vagus nerve
10
Q
cranial terminal ganglion
A
- ciliary ganglion
- pterygopalatine ganglion
- submandibular ganglion
- otic ganglion
11
Q
oculomotor nerve CNIII
A
- parasympathetic
- terminal ganglion- ciliary ganglion
- target effectors- ciliary muscle and constrictor pupillae
12
Q
ciliary mucles
A
- has parasympathetic innervation starts in midbrain and travels with oculomotor nerve and synapses at ciliary ganglion -> postganglionic fiber travels along V1 fibers and ends at ciliary muscle
- sympathetic- cell bodies at T1-L2 -> going through ventral root of spinal nerve
- paravertebral ganglion and up the sympathetic chain
- superior cervical ganglion organ nerve ciliary muscle
13
Q
facial nerve CN VII
A
-2/3 branches include parasympathetic
-ganglion- pterygopalatine
-target- lacrimal gland
-chorda tymapni
-
14
Q
which major foramen does the facial nerve pass through before it splits into 3 distinct branches
A
-internal acoustic meatus
15
Q
submandibular gland
A
- parasympathetic- pons -> facial nerve (chorda tympani) -> submandibular ganlgion -> V3 fibers (lingual nerve) -> submandibular gland
- sympathetic -> T1-L2 -> white ramus -> paravertebral ganglion -> up sympathetic chain -> superior cervical ganglion -> organ nerve -> submandibular gland
16
Q
glossopharyngeal nerve
A
- parasympathetic
- terminal ganglion- otic ganglion
- target effectors- parotid gland
17
Q
vagus nerve
A
- transmits a lot pf parasympathetic (80% of all parasympathetic preganglionic axons are transmitted through the vagus nerve)
- parasympathetic-
- preganglionic axons project to intramural ganglia of many organs (heart, tracheobronchial tree, most abdominal organs to splenic flexure)
18
Q
splenic fixture
A
-between transverse and descending colon on the left side of the body
19
Q
stomach
A
- parasympathetic- medulla oblongata -> vagus (abdominal aortic plexus) -> intramural ganglion -> intramural ganglion -> short nerves -> stomach
- sympathetic- T1-L2 (T5-T9) -> white ramus -> paravertebral ganglion -> splanchnic nerve -> celiac ganglion -> organ nerve -> stomach
20
Q
collateral abdominal ganglia
A
- there are 3
- T5-T9 -> celiac ganglion (stomach, liver, gallbladder, spleen, pancreas, kidney)
- T9-T12 -> superior mesenteric ganglion (small intestine and first part of large intestine)
- T12-L2 -> inferior mesenteric ganglion (lateral part of large intestine, rectum, pelvic organs)
- distribute the postganglionic fibers to the abdominal contents (foregut, midgut, hindgut)
21
Q
parasympathetic outflow: S2-S4
A
- sacral outflow- S2-S4
- pelvic splanchnic nerves come off- 3 (preganglionic travel here)
- hypogastric plexus- preganglionic nerves merge here)
- preganglionic axons project/synapse to intramural ganglia of almost all organs inferior to the splenic flexure:
- descending colon
- rectum
- bladder
- reproductive organs
22
Q
vagus
A
- comes out of the skull and descends
- 80% of parasympathetic innervation
- thorax and abdomen
23
Q
bladder
A
- parasympathetic:
- S2-S4
- pelvic splanchnic nerves
- intramural ganglion
- short nerves
- bladder
- sympathetic:
- T1-L2 (T10-L2
- white ramus
- paravertebral ganglion
- down sympathetic chain
- splanchnic nerve
- inferior mesenteric ganglion
- postganglionic fiber
- bladder
24
Q
S2-S4 (preganglion)
A
- goes through hypogastric plexus
- targets lower digestive
- pelvic (various)
25
Vagus (CN X): preganglion
- goes through cardiac plexus -> targets heart
- goes through pulmonary plexus -> tracheobronchial tree
- goes through esophageal plexus -> esophagus, stomach
- goes through abdominal aortic plexus -> abdominal (various)
26
autonomic plexus
- usually include both sympathetic and parasympathetic axons,
- no neural signaling occurs between these systems though
27
parasympathetic nervous system function
- rest and relaxation responses
- energy conservation
- maintaining resting homeostasis
- counteracts sympathetic responses
- always "on"
- some organs have more parasympathetic and sometimes more sympathetic signaling
- discrete and localized effects: activation of a single organ -> no mass activation (unlike symp)
28
examples of parasympathetic effects
- heart: decreased heart rate, weakened contractions, high blood pressure
- respiratory system: decreased diameter of airways
- face: pupil constriction, visual accommodation (close vision), increased saliva production
- digestive: increased smooth muscle motion, increased secretory activity
- bladder: smooth muscle contraction
- reproductive organs: erection of penis of clitoris (you feel safe)
29
visceral afferent
- unlocalized sensation (referred pain)
- subconscious receptor signaling (ex. CO2 concentration)
- provokes responses from autonomic responses
- associated with neurons of most internal organs
- go back to CNS or reflex arch in CNS to provokes a response
- pain types:
- ischemia (lack of O2) -> symp
- cramping -> symp
- distension (full tummy or full bladder) -> parasympathetic
- inflammation -> symp
30
somatic sensory
- localized sensation
- conscious perception (usually)
- associated with sensory neurons of skin, muscles and tendons
31
visceral afferent pathways
- follows path taken by sympathetic efferent
- afferent neurons DO NOT synapse in prevertebral or paravertebral ganglia (single peripheral neuron to CNS)
- afferent neuron cell bodies in posterior root ganglion of spinal nerve
- peripheral receptor -> CNS
32
referred pain
- particularly strong visceral sensations are frequently perceived consciously as pain in specific dermatome regions
- relevant visceral sensory fibers enter the spinal cord at the same level as somatic sensory fibers of that dermatome
- somatic sensory signal at the same level of spinal cord as visceral sensory signal
- appendix inflammation -> pain in belly button
33
visceral afferent pathways
- follows path taken by sympathetic efferent
- TWO EXCEPTIONS:
- follow path taken by parasympathetic in
1. tracheobronchial tree, heart, abdominal viscera -> follows vagus
- 2. distension of pelvic organs (bladder, uterus) -> follows pelvic splanchnic nerves
34
visceral sensory signal resulting from ischemia of the bladder is collateral to which nerve
- sacral splanchnic nerves (sympathetic)
- distension follows pelvic splanchnic nerves
- ischemia travels with sacral splanchnic nerves (sympathetic)
35
labor pain
- visceral afferent
- cervical distension (cervix dilation) -> follow a parasympathetic pathway -> pelvic splanchnic via S2-S4
- cramping of uterus (uterine contraction) -> follow a sympathetic pathway T10-L1
36
visceral afferent function
-provoke an autonomic response
-ex. micturition:
-distension of bladder
-visceral afferent signals CNS
-synapse at spinal cord
-parasympathetic
-
37
sensory receptors are specialized
- only certain kinds of stimulation
| - convert stimulation to nerve impulse
38
general somatic senses
- touch
- temperature
- pain
- proprioception
39
special somatic senses
- smell (chemoreceptors)
- taste (chemoreceptors)
- vision (photoreceptors)
- hearing (mechanoreceptors)
- equilibrium (mechanoreceptors)
40
chemoreceptors
- specific molecules in fluid
| - taste, smell
41
thermoreceptors
- identify changes in temperature
- free nerve endings- epidermis
- not all nociceptors are also thermoreceptors
- same free nerve endings at thermoreceptors in the skin
42
nociceptors
- pain receptors
- chemical changes
- free nerve endings- epidermis
- not all nociceptors are also thermoreceptors
- same free nerve endings at thermoreceptors in the skin
43
mechanoreceptors
- distortion of plasma memberane (various)
- baroreceptors- blood vessel stretch
- touch
- proprioception
- tactile corpuscule- papillary layer of dermis, discriminative touch (fine touch)
- lamellated corpuscule- reticular layer of dermis, coarse touch, deep pressure, vibration
- proprioception in mechanoreceptors is in sensory nerve ending of muscle spindles- detect stretching of the surrounding muscle fibers (change in plasma membrane)
44
photoreceptors
- light intensity, color, motion
| - rods, cones
45
what kind of sensory receptors are associated with sensing the movement of arm hairs when we put on a shirt in the morning
-mechanoreceptors
46
special senses: smell: chemoreceptors
- CN I
- olfactory mucosa
- mucus membrane of olfactory epithelium -> chemoreceptors are here
- lines superior region of nasal cavity
- traps and dissolves an odorant
- stuffy nose -> odorants need to make their way up to the mucus membrane
- olfactory receptors- cells stimulated by odorants
- modified bipolar neurons
- each bind to a small number of odorants
- humans can perceive 1000s of odorants
- supporting cell- sustain and support receptor cells
- basal cells- cell population that continuously replace receptor cells (receptors are damaged by chemicals)
- bipolar neurons transmit signal (after binding to olfactins) through the cribriform plate to the olfactory bulb
- olfactory bulb- synapse of CN1 with interneurons, enlargement of olfactory tract (cell bodies)
47
why does sniffing help us to perceive smells more strongly
- brings more odorant to the olfactory mucosa
| - increases air pressure and turbulence -> allows larger odorants to come to the olfactory mucosa
48
special senses: taste: chemoreceptors
- paillae- tissue elevations of the tongue composed of epithelium and connective tissue (there are 4 on tongue)
- filiform papilla- pointy, move food around by friction, bumps
- fungiform papilla- within this papillae there are taste buds, rounded
- vallate papilla- most taste buds on the side walls of this papilla are here, V shape, back of tongue
- foliate papilla- childhood taste buds are in here
- taste buds- containing gustatory receptors (chemoreceptors) are distributed within fungiform and vallate papillae of adults
- bind to chemicals
49
tastebuds
- gustatory cells- cells stimulated by tastants in our saliva
- supporting cells- sustain and support gustatory cells
- basal cells- cell population that continuously replaces short lived gustatory cells
- inside the papillae
50
gustatory discrimination
- taste receptors are chemoreceptors for various compounds dissolved within salvia
- different chemoreceptors for each:
- sweet- organic compounds
- salt- metal ions
- sour- acids
- bitter- alkaloids
- umami amino acids
51
innervation of the tongue
- muscles: intrinsic, genioglossus, hypoglossus, styloglossus, palatoglossus
- motor innervation- vagus to palatoglossus, hypoglossal to others
- somatic sensory innervation- trigeminal (mandibular V3), glossopharyngeal
- special sensory innervation (taste)- facial (chorda tympani) and glossopharyngeal
- posterior 1/3- glossopharyngeal (somatic sensory and taste)
- anterior 2/3- facial (chorda tympani) -> taste, trigeminal V3 (somatic sensory)
- epiglottis- has some special sensory taste (gustatory receptors) from vagus innervation
52
special senses: vision: photoreceptors
- fibrous layer- dense fibrous connective tissue
- white fibrous tissue surrounds most of the eye- sclera
- clear structure- allows light to pass through eye
- ciliary body- accommodation reflex (shape of lens) -> vascular tunic
- iris- pupil dilation and constriction (vascular tunic)
- neural tunic- retina, photoreceptors are here
- fibrous -outer layer : sclera and cornea
- vascular tunic- middle layer: iris, ciliary body, choroid
- neural tunic- inner layer: retina (photoreceptors and neurons)
53
muscles in eye
- iris
- dilator pupilae muslces travel radial from center to edge of pupil
- contraction of dilator pupillae muscles pull from center outward -> open the pupil
- constrictor pupillae- constriction inwards -> constricts pupillae -> closes pupil
- ciliary muscles- relaxed -> elongated -> suspensory ligaments have tension -> lens is flatter; contraction of ciliary muscle -> goes from elongated to rounded state -> less tension of suspensory ligaments
54
lens
- part of the outer fibrous layer
- made of dead cells
- cells filled with crystallin (clear)
- shape of lens determines degree of light refraction -> determines focal length
- bending lights to it hits the retina properly
- suspensory ligaments and ciliary muscles help determine shape of lens
- distance- sympathetic signal (superior, cervical ganglion) -> ciliary muscles are relaxed -> suspensory ligaments taut -> flattens lens
- near- (accommodation reflex) -> parasympathetic signal by oculomotor nerve -> ciliary muscles contract -> suspensory ligament relaxed (no tension) -> you can see near
55
accommodation reflex
- rounding of the lens for near focus
- parasympathetic signal by oculomotor nerve
- ciliary muscles contract -> suspensory ligaments are not taut anymore (relaxed) -> rounder shape -> near sight
56
pupil/irisu
- aperture size determines amount of light that is refracted
- low light -> dilator pupillae contracts -> sympathetic autonomic signal (superior cervical ganglion) -> contraction of dilator pupillae -> pupil dilates
- bright light -> sphincter pupillae contracts -> parasympathetic (oculomotor) signal -> pupil constricts
57
lens: cataracts
- region of opacity within the lens that may eventually obscure entire field of vision
- blurry vision due to opacity
- difficulty with colors
- reduced focus
- random refraction of light
- risk factors: old age, diabetes, intraocular infection, UV light exposure
58
lens- presbyopia
- inability to focus on near objects
- related to inflexibility of lens
- age related
- lens no longer bends or returns to its round shape as easily as it once did
- accommodation reflex -> tension/contraction in ciliary muscle -> suspensory ligament relaxed (no tension) -> bend light correctly for near locations
- if there is an issue with this you will need glasses
59
choroid
- most of vascular tunic (thick)
- nutrient supply for retinal layer
- absorbs extra light (so it doesnt hit photoreceptors twice)
- arteries and veins in the choroid layer
60
retina
- pigmented layer: transport of nutrients and absorbing extra light
- neural layer: photoreceptors and neurons
61
bipolar neurons
- transmits from photoreceptors to ganglion
| - passes through ganglion layer to photoreceptor layer to rods and cones
62
nocturnal animals
- eyes glow when you shine a light on them
- due to extra layer between retina and choroid
- instead of absorbing it reflects the light
- this layer is called the tapetum lucidum
- less light entering the eye (fewer photon) -> 2 shots to absorb light -> on the way in and way out
- lose some focal acuity on the way out tho (tradeoff)
63
retina
- photoreceptors
- 125 million rods: black and white
- 7 million cones: color
- different types of cones that are more sensitive to certain colors
64
optic disc
- part of retina
- few photoreceptors
- vascularized
- dominated by neurons and blood vessels
65
macula lutea
- part of retina
- darkened area lateral to optic disc
- in the portion of the retina that receives a focus of light
- has high cone concentration in the center (fovea centralis)
- center of visual field
66
fovea centralis
- has high cone concentration
| - pit in its center on the macula lutea
67
what impact would the destruction of the macula lutea have
- loss of some color vision
| - center of visual field lost
68
retina: macular degeneration
- degeneration of the macula lutea
- typically occurs in older people
- loss of photoreceptors
- and thinning of pigmented layer
- eventual vision loss in the center of the visual field and diminished color perception (fovea centralis cone concentraion)
69
innervation of eye
- ganglion -> bipolar neurons -> optic nerves -> brain ->
| - visual field of left eye goes to visual cortex on right side of cerebrum
70
lacrimal apparatus
- lacrimal gland- superior, lateral to eye, produces tears
- lacrimal puncta- tears move through here, transmit tears into nasal cavity ->
- nasolacrimal duct ->
- inferior nasal concha
- parasympathetic innervation of lacrimal gland from facial VII
- greater petrosal branch -> hiatus of facial canal -> foramen lacerum -> pterygopalatine ganglion -> parasympathetic to lacrimal gland
71
extrinsic muscles of eye
- levator palpebrae superioris (oculomotor nerve) -> dilator of eyelid
- attaches to upper eyelid
- opens eye
- sphincter of eyelids- orbicularis oculi -> facial nerve
- palpebral (gentle close) and orbital (tight close) portion
- closing of eye
72
extrinsic muscles that move the eye
- superior oblique (trochlear)
- lateral rectus (abducens)
- inferior oblique (oculomotor)
- superior rectus (oculomotor)
- medial rectus (oculomotor)
- inferior rectus (oculomotor)
73
adduction of eye
- looking at nose
- medial rectus
- pulls on medial side of front of eyeball
- inferior rectus
- superior rectus
74
abduction of eye
- looking towards ear
- lateral rectus
- pulls on lateral side of front of eyeball
- superior oblique- pulls from back of eye on the superior lateral side
- inferior oblique- pulls from back of the eye inferiorly laterally
75
elevation of eye
- looking up
- superior rectus
- inferior oblique- pulls from back of the eye inferiorly
76
depression of eye
- looking down
- inferior rectus
- superior oblique- pulls from back of eye on the superior lateral side
77
orbital vs. optic axis
- orbit of the eye
- optic plane is directly forward
- the muscles comes from the back of the orbit
- the orbit is angled from medial to lateral
- explains why superior and inferior recti are adductors of the pupil (bc they are coming at an angle)
78
starting with the pupil facing straight forward, what would the motion of the eye be if both superior rectus and inferior oblique contracted at the same time
- superior rectus- adduction and elevation
- inferior oblique- elevation and abduction
- adduction and abduction cancel out
79
somatic sensation of the eyeball
- somatic sensory
| - trigeminal nerve: ophthalmic division (V1)
80
hearing
- transfer of mechanical vibrations
- auricle -> cochlea
- auricle- fleshy cartilaginous structure surrounding outer ear
- cochlea- has the mechanoreceptors
- middle ear- ear ossicles
- inner ear- cochlea
81
outer ear
- lobe
- helix
- antihelix
- antitragus
- concha
- tragus
82
pathway of hearing
external ear -> external auditory meatus -> tympanic cavity (eardrum) -> auditory (eustachian) tube -
>
83
tympanic cavity
- ear drum
- tympanic membrane: taught membrane
- vibrates based on speed and intensity
- middle ear
84
auditory (eustachian) tube
- connects middle ear to nasopharynx
| - corrects pressure within middle ear
85
auditory ossicles
- malleus- hammer
- incus- envil
- stapes- stirrup
- vibrations pass from tympanic membrane -> malleus -> incus -> stapes -> oval window in petrous bone (temporal) -> inner ear
- tensor tympani- from nasopharynx to malleus (innervation by trigeminal (V3)
- stapedius- form tympanic cavity to stapes (innervation by facial nerve)
- contraction of these muscles during loud noise to protect auditory ossicles
86
inner ear
- oval window -> inner ear
- transmitted through fluids in the inner ear
- go to the cochlea
- pick up wavelength and intensity
- mechanoreceptors in cochlea
- cochlear branch -> vestibulocochlear nerve (special sense of hearing and equilibrium)
87
middle ear
- auditory tube
| - ear ossicles
88
equilibrium
- proprioception
- mechanoreceptors
- inner ear
- semicircular canals
- vestibule
89
semicircular canals
- within temporal bone
- closely related to the cochlea
- equilibrium
- sensation are picked up mechanoreceptors in the semicircular canals of vestibule -> vestibulocochlear nerve
- bony labyrinth- contains soft tissue structures
- membranous labyrinths- lines the bony labyrinth
- the soft tissues includes equilibrium structures: vestibule, cochlea, semicircular canals
90
membranous labyrinth
- surrounds:
- saccule and utricle
- cochlear duct
- semicircular ducts
- contains the fluids
- cochlea has 3 fluid filled spaces
91
perilymph
- within the membranous labyrinth
- external to the organs of hearing and sensation
- within the vestibule- picks up vibrations and sends to cochlea, semicircular canals
92
endolymph
- within the hearing and sensation organs
| - within cochlea duct, semicircular ducts, utricle, saccule
93
vestibular apparatus
- within the vestibule
- associated with balance
- macula- hairs
- hairs are the mechanorecpeotrs associated with balance
- statoconic membrane-otolithic layer- gelatinous fluid attached to hairs
- vestibular neurons
- when macula changes orientation due to movement of head -> sensed
- when upright -> hairs are up
- when looking down -> hairs are pushed down
- head tilt
94
cochlea
- hearing only (not equilibrium
| - cochlear branch
95
given that the macula within the inner ear vestibule function to detect linear motion of the head, what cranial nerve transmit signals from the maculae to the brain
-vestibular branch of CN VIII
96
rotational movement
- semicircular ducts
- fluid passes through ducts
- fluid will move more quickly when we rotate parallel to the duct
- flows through the ampulae at the ends of the duct
- one ampulae per duct
- within the ampulae there is a cupula -> surrounds many hairs
- ampulla
- as fluid flows past the cupula the cupula is pushed and therefore the hairs -> increase in nerve impulse
- tells us the axis of rotation
- fluid- endolymph
97
semicircular canal orientation
- posterior semicircular canal- coronal plane -> tilt head form side to side
- anterior semicircular canal- sagittal plane -> nod head yes
- lateral semicircular canal- horizontal plane -> shake head no
- complex rotations can be in different canals
98
macula
- mechanoreceptor hairs
- vestibular nerve branches
- hairs move with gravity
- increases and decreases neurotransmitters
99
ampulla
- fluid flows faster in one semicircular duct than another
- direction of rotation in space
- detects head motion
- vestibular branch
100
stapes
-at the oval window
101
cochlea
- internal space is filled with perilymph
- external auditory canal -> tympanic membrane -> vestibule -> scala vestibuli -> scala tympani -> round window
- scala vestibuli is a part of the cochlea
- scala media- cochlear duct
- strength of wave -> intensity
- wavelength will also only go for certain distance as well
102
which structures within the cochlea are filled with endolymph
- cochlear duct
| - scala tympani and scala vestibuli do NOT -> they have perilymph
103
tinitis
- damage to hair cells
- damage to mechanoreceptors
- injuries to nervous system within the cranial nerve
104
pathway of equilibrium
-external auditory canal -> tympanic membrane -> ear ossicles -> window -> scala vestibuli -> cochlear duct -> hairs move within basil membrane -> vibrations -> scala tympani -> round window -> middle ear
105
endocrine system
- communication system
- maintain homeostasis
- signals coming from CNS -> transmitted by other glands
- modify organ function or development
- excrete hormones into extracellular space and picked up in blood to pass through whole body -> some cells have the receptors and some dont
- slower signal
- no duct
- neural communication- chemical communication, specific
106
central endocrine system
- hypothalamus
- pituitary (2 parts)
- pineal gland
107
peripheral endocrine system
- thyroid gland
- parathyroid glands
- pancreas
- adrenal glands (2 parts)
- gonads
108
hypothalamus
- inferior on the diencephalon
- different nuclei that excrete different factors
- infundibulum connects the hypothalamus to the pituitary
- neurohypophysis- posterior
- adenohypophysis- anterior
109
pituitary
- recieves signals from the hypothalamus
- neurohypophysis-neural tissue (posterior)
- paraventricular nucleus -> oxytocin -> bonding, lactation, late pregnancy
- supraoptic nucleus -> antidiuretic -> high salt ->
- adenohypophysis- glandular tissue (anterior)
- hormones are stored in neurohypophysis (posterior) from the hypothalamus and produced in adenohypophysis (anterior)
110
hypothalamic-hypophyseal portal system
- two capillary beds that are directly connected to each other -> allows for hormones to go from hypothalamus to the anterior adenohypophysis directly (potent)
- adenohypophysis (anterior pituitary)
- 2 parts: primary capillary plexus (receives hormones from pituitary) and secondary capillary plexus
- GHRH- growth hormone releasing hormone- cause the glandular tissue in adenohypophysis to produce GH -> long bone growth
- GH hormone
111
adenohypophysis hormones
- growth hormone (GH)
- adrenocorticotropic (ACTH) -> cortical layer of adrenal gland
- follicle stimulating (FH) -> gonads
- luteinizing (LH) -> gonads
- thyroid stimulating (TSH) -> thyroid
- hormone is produced here
- releases hormones that cause production of other hormones
112
neurohypophysis hormones
- antidiuretic (vasopressin)
- oxytocin
- hormone is produced in the hypothalamus and passed to neurohypophysis
113
pineal gland
- central
- found in diencephalon
- epithalamus
- produces melatonin (circadian)
- increase and decrease depending on light and time
- based on circadian rhythm
- problems are related to seasonal...
114
thyroid gland
- peripheral
- inferior/surrounding to trachea
- receive blood from external carotid and superior thyroid artery
- receives thyroid stimulating hormone through the arteries
- blood stream also carries high level of serum calcium -> produces calcitonin
- calcitonin reduces the level serum calcium -> increase activity of osteoblasts
- calcitonin (and all other hormones produced) is released into venous system -> superior thyroid -> jugular -> brachiocephalic -> vena cava
115
release of calcitonin serves to reduce the level serum calcium through various mechanisms. you also know that bone is a major reservoir of calcium -> given this knowledge, what type of bone cell activity is upregulated by calcitonin
-osteoblast
116
parathyroid
- peripheral
- produce an opposite effect to thyroid
- posterior side of thyroid
- 4 glandular structures
- if there is low amount of serum calcium -> parathyroid hormone -> osteoclasts are activated (resorption of blood)
- lactation
117
pancreas
- peripheral
- elongated
- between spleen and duodenum
- in combination with the liver produces bile (exocrine secretion)
- produce digestive enzymes
- exocrine glands- produce a substance that is released in a duct
- also an endocrine organ
- produces insulin (endocrine) -> breaks down glucose in blood
- lack of insulin -> type 1 diabetes
118
adrenal glands
- 2 layers: cortex (outer) and adrenal medulla (inner)
- superior to kidneys
- cortex- produces corticoids (long term stress)
- adrenal medulla- produces epinephrine and norepinephrine (short term stress)
- high vascularized -> very quick signaling
- stress response
119
stress response: fast
- the fast arm (within seconds)- activation of the sympathetic nervous system
- sympathetic nervous system signal -> adrenal medulla produces epinephrine (adrenalin), norepinephrine
- very fast
- fight or flight
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stress response: long term
- hypothalamus releases the CRH (corticotropin releasing hormone
- portal system
- makes the anterior pituitary to release the ACTH (adrenocorticotropic hormone)
- causes the adrenal cortex to produce glucocorticoids
- slow arm (within minutes)- activation of the hypothalamic-pituitary-adrenal (HPA) axis
- hormones are passing through blood vessels along a long path
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stress response effects
stress causes:
- reproduction (suppresses)
- growth (suppresses)
- digestion (suppresses)
- cardiovascular tone (enhances)
- glucose breakdown (enhances)
- glucose storage (suppresses)
- immune system (immediately enhances, then suppresses)
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gonads
- peripheral
- leydigs cells in the testes of males produce androgens (testosterone) -> increase sperm, development of male organs
- follicle stimulating hormone from the
- estrogens -> maturation of female gametes and gonads -> produced in the walls
- progesterone is from the primary corpus luteum -> produces by gonads -> maintains menstrual cycle
