Test 4 PNS, ANS, Special Senses & Endocrine Flashcards
0
Q
5 sensory receptor classification by stimulus
A
- mechanoreceptor
- chemoreceptor
- photoreceptor
- thermoreceptor
- nociceptor
1
Q
what is sensation?
A
awareness of changes in the internal and external environments
2
Q
3 sensory receptors classifications by location
A
- exteroceptor
- interoceptor
- proprioceptor
3
Q
2 sensory receptor classifications and their functions by complexity
A
- simple - tactile sensation
2. complex - sense organs
4
Q
two types of simple sensory receptors
A
- free (naked) nerve endings - peripheral end of sensory axon, usually respond to pain and thermal stimuli
- encapsulated - enclosed by connective tissue
5
Q
What are Merckle’s cells (discs)?
A
specialized skin cells that release transmitter onto peripheral sensory nerve terminals
6
Q
what are Meissner’s corpuscles?
A
encapsulated receptors found in superficial dermis that respond to light touch
7
Q
what are Pacinian corpuscles?
A
specialized encapsulated receptors in deep dermis that respond to (1) deep pressure when first applied and (2) vibration
8
Q
what are Ruffini’s corpuscles
A
encapsulated receptors located in (1) dermis (2) subcutaneous and (3) joint capsules that respond to (1) deep continuous pressure and (2) stretching
9
Q
what are muscle spindles?
A
modified muscle fibers that detect muscle stretch and contract preventing over stretching (damage to muscle)
10
Q
what are golgi tendon organs?
A
proprioceptors in tendons that cause muscle (muscle spindles) to relax after 30 seconds
11
Q
what two encapsulated cell types are responsible for proprioception?
A
- muscle spindles
2. golgi tendon organs
12
Q
what is a modality?
A
one feature of a complex stimulus; for example, temperature, pressure, sound or taste.
13
Q
what is adaption?
A
a reduction in sensitivity to constant stimulus
14
Q
what receives input from many classifications of receptors?
A
primary somatosensory cortex
15
Q
what is the three layer structure of nerves?
A
- Epineurium surrounds fascicles and forms nerve
- Perineurium surrounds endoneuroum forming fascicles
- Endoneurium surrounds neurons
- Schwann cells surround axon
16
Q
what happens to axon when an axon is crushed or cut?
A
axon distal to injury dies and healing may begin
17
Q
how is a nerve fiber regenerated?
A
surviving schwann cells release growth factor and form a regeneration tube that the axon regrows through
18
Q
where do the first 2 pairs of cranial nerves originate from?
A
forebrain
19
Q
where do 10 of the 12 cranial nerves originate from?
A
brain stem
20
Q
what cranial nerve is the exception of serving only head and neck structures
A
vagus nerve
21
Q
CN I name and function
A
Olfactory, sensory (smell)
22
Q
CN II name and function
A
Optic, sensory (vision)
23
Q
CN III Name and Function
A
Oculomotor, Somatic (Eye movement) and autonomic (pupil constriction) motor
24
CN IV Name and Function
Trochlear, Motor (down and out eye movement)
25
CN V name and function
Trigeminal, motor and sensory of face, 3 divisions
26
CN VI name and function
abducens, motor (eye movement)
27
CN VII name and function
Facial, motor and sensory, 5 divisions
28
5 divisions of facial nerve (superior to inferior)
1. temporal
2. zygomatic
3. buccal
4. mandibular
5. cervical
29
CN VIII name and function
vestibulocochlear, sensory (equilibrium and hearing)
30
CN IX name and function
glossopharyngeal, motor and sensory. innervates tongue and pharynx for swallowing, salivary gland and taste
31
CN X name and function
vagus, sensory and motor (heart, lungs, abdominal viscera)
32
(6) what activities does vagus nerve control
1. taste
2. swallowing
3. voice
4. heart rate
5. breathing
6. digestive activity
33
CN XI name and function
accessory, motor (larynx and pharynx and head movement)
34
CN XII name and function
hypoglossal, motor (food mixing and manipulation while chewing, tongue contributions to swallowing and speech)
35
Mnemonic for cranial nerve names
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Old
Olympus'
Towering
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A
Finn
Viewed
Germans
Viewing
A
Hopp
```
36
Mnemonic for cranial nerve types
```
Some
Say
Marry
Money
But
My
Brother
Says
Big
Butts
Matter
Most
```
37
How many pairs of spinal nerves are there and what do they innervate?
31, all areas except head and some neck regions
38
Five main segments of spinal nerves and the nerves they contain
1. Cervical C1-C8 (one more than # of vertebrae)
2. Thoracic T1-T12
3. Lumbar L1-L5
4. Sacral S1-S5
5. Coccygeal C0 (very small)
39
what is a dermatome?
an area of skin innervated by nerves from a single spinal nerve
40
5 Steps of Reflex Arc
1. receptor
2. sensory neuron
3. integration center in spinal cord
4. motor neuron
5. effector
41
2 Things ANS does
1. controls slow routine body functions without conscious control
2. Shift resources in situations requiring instantaneous diversion of energy
42
3 characteristics of ANS motor neurons
1. innervate smooth muscle, cardiac muscle and glands
2. operate via subconscious control
3. have viscera as most of their effectors
43
which is faster, Autonomic or Somatic and why?
Somatic, axons are heavily myelinated
44
Comparison of sympathetic pre and post ganglionic neurons
sympathetic has short pre ganglionic neuron and long post ganglionic neuron
45
Comparison of parasympathetic pre and post ganglionic neurons
parasympathetic has long pre ganglionic neuron and short post ganglionic neuron
46
effectors for ANS
cardiac muscle, smooth muscle, glands
47
What is the difference between ANS and SNS target organ response?
SNS only releases excitatory ACh where ANS releases ACh or norepinephrine and the effect is inhibitory or excitatory
48
What does "two neuron chain" refer to in ANS?
Two neurons to get from CNS to effectors because there is a ganglion in the middle and one synapse.
49
5 main ways ANS and SNS differ
1. myelination
2. one vs 2 neuron chain
3. length of pre and poat ganglionic neurons (ANS only)
4. effector organs
5. neurotransmitters
50
Three activities of parasympathetic division
1. digestion
2. defecation
3. diuresis
51
When the parasympathetic system dominates what are 6 body characteristics
1. blood pressure low
2. heart rate low
3. respiratory rates low
4. gastrointestinal tract activity is high
5. skin is warm because blood is in skin
6. pupils are constricted
52
What are the two main differences between the anatomy of sympathetic and parasympathetic divisions?
1. where the ganglia are
| 2. where they exit the spinal cord (sym. T1 -L2 para. S2-S4)
53
where are parasympathetic ganglia located?
on the target organ (long preganglionic, short postganglionic)
54
where are sympathetic ganglia located?
near the spinal cord
55
where do parasympathetic nerve fibers exit?
1. cranial nerves
| 2. sacrally
56
where do sympathetic nerve fibers exit?
T1-L2
57
Why is autonomic nervous system considered sensory as well as a motor system?
There are sensory receptorslocated on viscera
58
What is referred pain?
Visceral pain is perceived as somatic in origin
59
Why does referred pain occur?
Visceral pain afferents piggy back (they are carried) by somatic nerve fibers
60
If sympathetic system dominates what are 4 characteristics of the body
1. Increased heart rate and force
2. Dilated air passages
3. Decreased digestive activity
4. inhibited urinary system
61
What is ANS tone?
The magnitude of a division (sympathetic or parasympathetic) considered to be acting independently and the effects it brings.
62
What are cholinergic fibers?
ANS fibers that release acetylcholine.
63
What are adrenergic fibers?
ANS fibers that release norepinephrine
64
Which ANS fibers are cholinergic fibers?
All preganglionic axons and all parasympathetic postganglionic axons
65
Which ANS fibers are adrenergic?
some sympathetic postganglionic axons
66
What two types of receptors will cholinergic fibers release onto?
1. nicotinic
| 2. muscarinic
67
What four types of receptors will adrenergic fibers release onto?
1. alpha 1
2. alpha 2
3. beta 1
4. beta 2
68
Effect of an alpha 1 stimulant?
excitatory, constrict blood vessels and dilate eyes
69
effect of alpha 2 stimulant?
inhibitory, promote blood clotting
70
effect of beta 1 stimulant?
excitatory, increase HR and beat strength
71
effect of beta 2 stimulant
inhibitory and excitatory, dilate bronchials and coronary vessels. more air, more blood
72
where are 3 places nicotinic receptors found?
1. all motor end plates (somatic targets)
2. all ganglionic neurons
3. hormone producing cells of adrenal medulla
73
What is the effect of ACh binding to nicotinic receptors?
Always stimulatory
74
Where are muscarinic receptors found?
All effector cells stimulated by postganglionic cholinergic fibers
75
Five effects of ACh binding to muscarinic receptors
1. Inhibitory or excitatory
2. Depends on receptor type of target organ
3. slows heart rate and strength of muscle contractions
4. Increases digestive activity
5. Constriction of the iris
76
Effect of Atropine?
Blocks parasympathetic effects (Bella donna and an antidote to nerve gas)
77
Effect of neostigmine
inhibits acetylcholinesterase and is used to treat myasthenia gravis
78
effect of tricyclic antidepressants
prolong the activity of NE on postsynaptic membranes
79
effect of OTC cold, allergy and nasal congestion relief
stimulate alpha adrenergic receptor
80
effect of beta blockers
attach mainly to beta 1 adrenergic receptors and reduce heart rate and prevent arrhyhmias
81
What is the difference between the areas sympathetic and parasympathetic effect body?
Parasympathetic exerts short-lived highly localized control
Sympathetic exerts long-lasting diffuse effects
82
3 reasons sympathetic activation is long-lasting
1. NE is inactivated more slowly than ACh
2. NE is an indirectly acting neurotransmitter, using a second-messenger system
3. Epinephrine is released into the blood and remains there until destroyed by the liver
83
What is the main integration center of ANS activity?
hypothalamus
84
What system exhibits subconscious influence on hypothalamus?
Limbic system via limbic lobe connections
85
Five levels of ANS control
1. cerebral cortex (frontal lobe)
2. limbic lobe
1&2 are subconscious
3. hypothalamus
4. reticular formation
5. spinal cord
86
Four centers of Hypothalamus
1. heart activity and blood pressure
2. body temperature, water balance and endocrine activity
3. emotional stages (rage, pleasure) and biological drives (hunger, thirst, sex)
4. reactions to fear and the "fight-or-flight" system
87
where are taste buds found?
inside papillae on tongue, cheeks and soft palate
88
what is the function of taste buds?
gustatory receptors
89
where are olfactory receptor cells?
olfactory bulb of olfactory (CN I) nerve in olfactory epithelium (roof of nasal cavity)
90
function of eyebrows
protect eye from sun
91
function of eyelids
protect and moisturize eye
92
function of eyelashes
protect and remove dirt and debris
93
function of conjunctiva
moisturize eye, membrane covering
94
function of lacrimal structures
tears
95
function of sclera
protects and shapes eye; provides anchor for eye muscles
96
function of cornea
lets light in and bends light as it enters eye
97
function of retina
contains photoreceptors (rods and cones)
98
function of rods
dim light & peripheral vision; black and white, fuzzy images
99
function of cones
bright light and high acuity; color, sharp images
100
what is the central fovea
light hits most directly; greatest cone concentration
101
what is the optic disc
blind spot where optic nerve exits eye
102
what are cataracts?
clouding of lens usually from age-related hardening and thickening
103
where is anterior chamber of eye located?
behind cornea and in front of lens
104
where is posterior chamber of eye located
behind lens
105
what fills is the anterior chamber of the eye?
aqueous humor
106
what fills the posterior chamber of eye?
vitreous humor
107
which humor of the eye regenerates?
aqueous humor
108
which humor of the eye is formed in embryo and lasts a lifetime?
vitreous humor
109
what causes Glaucoma?
drainage of aqueous humor is blocked
110
how does glaucoma cause damage to eye?
compression of retina and optic nerve can cause blindness
111
where in the eye is light focused on to?
retina (central fovea)
112
what is a normal shaped eye called?
emmetropic
113
what is an elongated eye that focuses light in front of retina called?
myopic (nearsighted)
114
what is a shortened eye that focuses light behind retina called?
hyperopic (farsighted)
115
what kind of lens corrects myopia?
concave lens
116
what kind of lens corrects hyperopia?
convex lens
117
what characterizes astigmatism?
unequal curves on lens or cornea
118
when happens when the light hits the retina to cause vision?
photoreceptors generate graded potentials that cause ganglion cells to generate action potentials that send a signal through optic nerve to occipital lobe of brain
119
what is the pinna?
also called auricle. outer ear made from elastic cartilage
120
what is the function of the auricle?
direct sound waves into external auditory canal
121
where is outer ear located?
extends from auricle to ear drum, runs through temporal bone of skull
122
what glands secrete ear wax?
ceruminous glands create cerumen
123
what is the tympanic membrane?
eardrum. made from connective tissue and separates outer and middle ear
124
what is the function of the ear drum?
vibrates when sound waves hit which causes ossicles to vibrate
125
order of three ossicles in ear
1. hammer
2. anvil
3. stirrup
126
proper name for hammer?
malleus
127
proper name for anvil?
incus
128
proper name for stirrup?
stapes
129
three non-bony structures of middle ear
1. oval window
2. round window
3. eustachian tube
130
what is the organ of corti?
hearing receptor organ
131
(7 steps) how does hearing occur?
1. sound waves directed by auricle
2. tympanic membrane vibrates
3. ossicles move
4. stapes moves against oval window causing perilymph to move
5. perilymph in scala tympani (cochlea) moves basilar membrane
6. hair cells in organ of corti move against tectorial membrane
7. signal sent down nerve
132
what is conduction deafness?
blocking of sound to inner ear
133
3 causes of conduction deafness
ear wax, middle ear inflammation, otosclerosis (fused ossicles)
134
what is sensoneural deafness
damage to neural structures of the ear
135
2 causes of sensoneural deafness
loss of hearing receptor cells by aging or loud noise
136
what two structures of inner ear create sense of equilibrium (balance)?
1. semicircular canals
| 2. vestibule
137
10 major endocrine organs from superior to inferior
1. pineal gland
2. hypothalamus
3. pituitary gland
4. thyroid gland
5. parathyroid glands
6. thymus gland
7. adrenal glands
8. pancreas
9. ovary (female)
10. testis (male)
138
5 non-major hormone producing tissues and organs
1. adipose cells
2. pockets of cells in walls of small intestines
3. stomach
4. kidneys
5. heart
139
what are autocrines
chemicals that exert their effects on the same cells that secrete them
140
what are paracrines
locally acting chemicals that affect cells other than those that secrete them (act on neighboring cells)
141
why are paracrines and autocrines not considered hormones
hormones are long-distance chemical signals
142
where are hormones secreted into?
extracellular fluid (usually blood)
143
three types of hormones
1. amino acid based
2. steroids
3. eicosanoids
144
hormones mostly belong to which class of hormones?
amino acid based
145
what are the two Amino acid based hormones mechanism of action called?
1. cAMP second messenger
| 2. PIP-Calcium second messenger
146
5 steps of cAMP second messenger action
1. hormone (first messenger) binds to receptor and G protein
2. G protein generates GDP from GTP
3. Activated G protein activates adenylate cyclase
4. adenylate cyclase generates cAMP (second messenger) from ATP
5. cAMP activates protein kinases which cause cellular effects
147
5 steps of PIP-Calcium action
1. hormone binds to receptor and activates G protein
2. G protein activates phospholipase enzyme
3. Phospholipase splits phospholipid PIP2 into two different second messengers, DAG and IP3
4. DAG activates protein kinases; IP3 triggers release of Ca2+ stores
5. Ca2+ (third messenger) alters cellular response
148
4 steps of steroid action
1. steroid diffuses easily into cell
2. steroid binds to receptor making a complex
3. complex travels into nucleus
4. complex binds to a DNA-associated receptor initiating transcription and protein production
149
how does target cell specificity work?
target cells must have specific receptors to which the hormone binds
150
3 factors of target cell activation
1. how much hormone is in blood
2. affinity of receptors to hormone
3. how hormone interacts with other hormones in binding to a receptor
151
3 factors affecting how much hormone is in the blood
1. rate of release of hormone
2. rate of removal of hormone
3. is the hormone attached to other things?
152
3 ways hormones are deactivated or removed from blood
1. degrading enzymes
2. the kidneys
3. liver enzyme systems
153
which hormones are attached to plasma proteins?
steroid and thyroid hormones. all other hormones are unencumbered
154
3 types of hormone interaction with the receptor
1. permissiveness
2. synergism
3. antagonism
155
what is permissiveness interaction?
one hormone cannot exert its effects without another hormone present
156
what is synergism interaction
more than one hormone produces the same effects on a target cell
157
what is antagonism interaction?
one or more hormones opposes the action of the other hormone
158
three types of stimuli that cause hormones to be synthesized and released
1. humoral (body fluids)
2. neural
3. hormonal stimuli
159
how does humoral stimuli cause hormone release?
hormones are secreted in direct response to changing blood levels of ions and nutrients
160
how are hormones released by neural stimuli in Sympathetic ANS?
preganglionic sympathetic nervous system fibers stimulate the adrenal medulla to secrete catecholamines
161
what is nervous system modulation?
nervous system can override normal endocrine function
ex. during stress hypothalamus and SNS take control of blood glucose levels
162
how are hormones released by hormonal stimuli?
hormones are released in response to hormones produced by other endocrine organs
163
what is the hypophysis?
pituitary gland. two-lobed organ that secretes several major hormones
164
what is the neurohypophysis and two hormones secreted by it?
posterior pituitary gland
1. ADH
2. Oxytocin
165
What is the adenohypophysis and what 5 hormones does it secrete?
anterior pituitary lobe and infundibulum
1. TSH
2. FSH/LH
3. ACTH
4. GH
5. PRL
166
what is the relationship between neurohypophysis and hypothalamus?
(1) Neurohypophysis is an extension of neurons of hypothalamus and it (1) receives stores and releases hormones from the hypothalamus
167
where are oxytocin and ADH synthesized?
hypothalamus, then transported to posterior pituitary
168
what does oxytocin do?
strong stimulant of uterine contraction
169
how is oxytocin regulated?
a positive feedback of oxytocin in the blood
170
what hormone triggers milk ejection ("letdown" reflex)
oxytocin
171
what does ADH stand for and do?
(1) antidiuretic hormone (2) prevents urine formation
172
when is ADH synthesized and released?
when osmoreceptors detect high solute concentration in blood
173
when is ADH not released?
when osmoreceptors detect low solute concentration in blood
174
why do you pee a lot when you drink alcohol?
alcohol inhibits ADH release and causes copious urine output
175
what do the six hormones of the adenohypophysis typicallydo?
regulate activity of other endocrine glands
176
What does GH stand for and what does it do?
Growth hormone, promotes protein synthesis and encourages the use of fats for fuel to promote cellular growth.
177
what cell types does GH target the most?
bone and skeletal muscle
178
what does TSH stand for and what does it do
1. thyroid-stimulating hormone that (2) stimulates the normal development and secretory activity of the thyroid gland [tropic hormone]
179
what is another name for TSH
thyrotropin
180
what causes Pituitary and Hypothalamus to stop releasing TSH?
rising thyroid hormone levels in blood
181
what does ACTH stand for and what does it do?
1. adrenocorticotropin hormone
| 2. stimulates the adrenal cortex to release corticosteroids
182
what is another name for ACTH
corticotropin
183
what hormone causes the release of ACTH
hypothalamic corticotropin-releasing hormone (CRH)
184
what three factors can trigger release of CRH
1. fever
2. hypoglycemia
3. other stressors
185
what are two gonadotropins and what do they stand for
1. FSH - follicle-stimulating hormone
| 2. LH - luteinizing hormone
186
what triggers gonadotropin production?
hypothalamic gonadotropin-releasing hormone (GnRH) during and after puberty
187
what are two things LH does in females?
1. trigger ovulation (expulsion of the egg from follicle)
| 2. promote synthesis and release of estrogens and progesterone
188
what hormones cause maturation of the ovarian follicle?
LH and FSH
189
what is another name for LH in males and what does it do?
(1) interstitial cell-stimulating hormone and (2) stimulates interstitial cells of testes to produce testosterone
190
what does PRL stand for and what does it do?
(1) prolactin (2) stimulates milk production by the breasts
191
what hormone triggers PRL?
hypothalamic prolactin-releasing hormone (PRH)
192
what hormone inhibits prolactin?
PIH (prolactin-inhibiting hormone)
193
when are two times blood levels of PRH are raised?
1. towards the end of pregnancy
| 2. suckling by a baby
194
what is the largest endocrine gland?
thyroid gland
195
what cells in thyroid gland produce thyroid hormone?
Follicle cells
196
what cells in thyroid gland produce calcitonin?
parafollicular cells
197
what is the body's major metabolic hormone?
thyroid hormone
198
thyroid hormone is composed of what two closely-related iodine-containing compounds?
1. T3 - triiodothyronine
| 2. T4 - thyroxine
199
what does calcitonin do?
inhibit osteoclast activity and inhibit release of calcium from bony matrix
stimulate calcium uptake and incorporation into bony matrix
200
what regulates calcitonin level?
humoral (calcium ion concentration in the blood) negative feedback mechanism
201
where are parathyroid glands located?
posterior aspect of thyroid gland
202
what are 3 things PTH does?
1. stimulates osteoclast activity
2. enhance reabsorption of Ca2+ and the secretion of phosphate by the kidneys
3. increase absorption of Ca2+ by intestinal mucosal cells
203
what inhibits PTH release?
Rising Ca2+ levels
204
what are 3 symptoms of hyperparathyroidism
soft bones, tumor, kidney stones
205
what are 2 symptoms of hypoparathyroidism
improper nerve impulse and respiratory paralysis
206
which part of adrenal glands acts as part of SNS?
adrenal medulla
207
what part of adrenal glands is made of glandular tissue?
adrenal cortex
208
what are three steroid hormones synthesized and released by adrenal cortex (corticosteroids)
1. mineralcorticoids (aldosterone)
2. glucocorticoids (cortisol)
3. gonadocorticoids (androgens)
209
what do mineralcorticoids do?
regulate the electrolyte concentrations of extracellular fluids
210
what are 2 things aldosterone does?
1. maintains Na+ balance by reducing excretion of sodium from the body
2. stimulates reabsorption of Na+ by the kidneys
211
what 3 things stimulates aldosterone secretion?
1. rising blood levels of K+
2. low blood Na+
3. decreasing blood volume and pressure
212
What are the four mechanisms of Aldosterone secretion?
1. Renin-angiotensin mechanism
2. Plasma concentration of sodium and potassium
3. ACTH causes small increases during stress
4. ANP (atrial natriuretic peptide) inhibits activity of zona glomerulosa
213
What are the four steps of Renin-Angiotensin mechanism?
1. angiotensinogen (liver) + renin (kidney) --> Angiotensin I
2. Angiotensin I + ACE (Angiotensin converting enzyme from lung) --> Angiotensin II
3. Angiotensin II --> aldosterone
4. Aldosterone affects nephron of kidney, retain H20
214
What are two things glucocorticoids do?
Help resist stress by:
1. keeping blood sugar levels relatively constant
2. maintaining blood volume and preventing water shift into tissue
215
What are two things cortisol provokes?
1. gluconeogenesis (formation of glucose from noncarbohydrates)
2. rises in blood glucose, fatty acids and amino acids
216
4 symptoms of excessive glucocorticoids
1. depress cartilage and bone formation
2. inhibit inflammation
3. depress the immune system
4. promote changes in cardiovascular, neural and gastrointestinal function
217
what is the main androgen?
testosterone
218
what 3 things do androgens contribute to?
1. onset of puberty
2. appearance of secondary sex characteristics
3. sex drive in females
219
when can androgens be converted into estrogens?
after menopause
220
what cells compose the adrenal medulla and what do they do?
chromaffin cells that secrete epinephrine and norepinephrine
221
4 effects of adrenal medulla hormones
"fight or flight"
1. blood glucose levels rise
2. blood vessels constrict
3. heart beats faster
4. blood diverted to brain, heart and skeletal muscle
222
which catecholamine is the more potent stimulator of the heart and metabolic activities
epinephrine
223
which catecholamine is more influential on peripheral vasoconstriction and blood pressure
norepinephrine
224
what part of adrenal gland causes long-term stress response?
adrenal cortex
225
what part of adrenal gland causes short-term stress response
adrenal medulla
226
where is pancreas located?
behind stomach
227
what are acinar cells?
cells of pancreas that produce an enzyme-rich juice used for digestion
228
where are hormones produced in the pancreas?
islets of Langerhans
229
what cells of islets of pancreas produce glucagon
Alpha cells
230
what cells of islets of pancreas produce insulin
Beta (diaBetaic)
231
what is the major target of glucagon?
liver
232
what are three things Glucagon promotes?
1. glycogenolysis - breakdown of glycogen to glucose
2. gluconeogenesis - synthesis of glucose from lactic acid and noncarbohydrates
3. Release of glucose from liver cells into blood
233
what are three effects of insulin
1. lowers blood glucose levels
2. enhances transport of glucose into body cells
3. counters metabolic activity that would enhance blood glucose levels
234
What are the target receptors for insulin called?
GLUT4 - muscles have more/higher affinity
235
what are three cardinal signs of DM?
1. polyuria - excessive urine output
2. polydipsia - excessive thirst
3. polyphagia - excessive hunger and food consumption
236
what is hyperinsulinism
excessive insulin secretion, resulting in hypoglycemia
237
what are three things ovaries are responsible for
1. maturation of the reproductive organs
2. appearance of secondary sexual characteristics
3. breast development and cyclic changes in the uterine mucosa
238
what do the testes do?
produce testosterone
239
what are 4 functions of testosterone
1. initiates maturation of male reproductice organs
2. causes appearance of secondary sexual characteristics and sex drive
3. necessary for sperm production
4. maintains sex organs in their functional state
240
where is pineal gland located?
hanging from the roof of the third ventricle
241
what does pineal gland secrete?
melatonin
242
what are two things melatonin is involved with?
1. day/night cycles
| 2. processes with rhythmic variations (body temperature, sleep, appetite)
243
where is thymus located
in thorax deep to sternum and above heart
244
what are the two major hormonal products of the thymus
thymopoietins and thymosins
245
what are thymopoitins and thymosins used for
development of T lymphocytes of immune system
246
What hormone does heart produce and what does it do
(1) atrial natriuretic peptide which (2) reduces blood pressure, blood volume and blood sodium concentration
247
what hormones are produced in gastrointestinal tract
enteroendocrine cells release local-acting digestive hormones
248
what do hormones from placenta do?
influence the course of pregnancy
249
what hormone do kidneys produce and what does it do
erythropoeitin which signals production of red blood cells
250
what is released by skin that is a precursor to vitamin D?
cholecalciferol
251
what hormone is released by adipose tissue and what does it do
(1) leptin (2) which is involved in the sensation of satiety and stimulates increased energy expenditure
