Lecture 24 -- Sensory organs II - Vision pt 2, Endocrine system pt 1 Flashcards
LO1: photoreceptor cells: indicate type of vision and visual pigment for each:
night vision
aka scotopic vision
rod –> have cilium specialized to absorb light
visual pigment – rhodopsin
LO1: photoreceptor cells: indicate type of vision and visual pigment for each:
day vision
aka photopic vision
cone
visual pigment – photopsin
LO1: photoreceptor cells: indicate type of vision and visual pigment for each:
color vision
LO1: photoreceptor cells: indicate type of vision and visual pigment for each:
color vision
aka trichromatic vision
cone
visual pigment – photopsin
LO1: photoreceptor cells: indicate type of vision and visual pigment for each:
rods and cones are both a specialized type of…
neuroepithelial cell
LO2: differentiate among the 3 types of cones responsible or color vision
how many cones are responsible for color vision?
3
LO2: differentiate among the 3 types of cones responsible or color vision
what are the 3 types of cones?
S-blue (short)
M-green (medium)
L-red (long)
LO2: differentiate among the 3 types of cones responsible or color vision
how is perception of colors formed?
based on mixture of nerve signals representing cones w/ different absorption peaks
LO3: summarize the steps in Phototransduction in the rods
define Phototransduction
conversion of light energy into action potentials in retina
LO4: sequence the light path from the photoreceptor cells to the optic nerve
light travels through to back of eye and hits retina:
1) photoreceptors
2) horizontal and amacrine cells
3) bipolar cell (1st order)
4) ganglion cell (2nd order) –> optic nerve
LO5: indicate the synaptic relationships of the retinal cells
photoreceptors (sequence and function)
retina –> photoreceptors
captures light and converts it into electrical signals (phototransduction)
LO5: indicate the synaptic relationships of the retinal cells
horizontal and amacrine cells (sequence and function)
retina –> photoreceptors –> horizontal and amacrine cells
interneurons that modify that rate of electrical firing in bipolar cells
LO5: indicate the synaptic relationships of the retinal cells
bipolar cells (sequence and function)
retina –> photoreceptor –> horizontal and amacrine cells –> bipolar cells
1st-order neurons of visual pathway
LO5: indicate the synaptic relationships of the retinal cells
ganglion cells (sequence and function)
retina –> photoreceptors –> horizontal and amacrine cells –> bipolar cells –> ganglion cells
2nd-order neurons of visual pathway
some act as photoreceptors that express melanopsin (a type of photopigment)
LO5: indicate the synaptic relationships of the retinal cells
the axons of the ___ form the ___
axons of retinal ganglion cells form the optic nerve
LO3: summarize the steps in phototransduction in the rods:
in light:
rhodopsin absorbs light
cis-retinal is converted to trans-retinal –> separates from opsin
glutamate secretion ceases
LO3: summarize the steps in phototransduction in rods:
in darkness:
rhodopsin absorbs no light
cis-retinal remains –> remains connected to opsin
glutamate secretion continues
LO6: trace the visual projection pathways:
what is the order?
fixation point –> optic nerve –> optic chasm –> optic tract –> pretectal nucleus –> superior colliculus –> lateral geniculate nucleus –> optic radiation –> occipital lobe (visual cortex)
LO6: trace the visual projection pathways:
what is stereoscopic vision?
ability to see environment in 3D
LO6: trace the visual projection pathways:
how is the optic nerve formed?
CN II
axons of retinal ganglion cells
LO6: trace the visual projection pathways:
explain hemidecussation in optic chiasm
1/2 of fibers from left and right optic nerves cross over to opposite sides of brain –>
decussation = cross-over
hemi = half
hemidecussation = half crosses over
LO6: trace the visual projection pathways:
what are the pretectal nucleus and superior colliculus made of?
what do they do?
optic nerve fibers from the melanopsin-containing ganglion cells
pretectal nucleus –> photo pupillary and accommodation reflexes
superior colliculus –> control visual reflexes of the extrinsic eye muscles
LO6: trace the visual projection pathways:
what happens in the occipital lobe (visual cortex)?
conscious visual sensation
LO7: identify the organs of the endocrine system and other organs containing tissues that secrete hormones in the human body
what are the organs of the endocrine system?
hypothalamus
pituitary gland
pineal gland
parathyroid glands
thyroid gland
adrenal glands
pancreas
LO7: identify the organs of the endocrine system and other organs containing tissues that secrete hormones in the human body
what are the organs w/ secondary endocrine functions?
heart
thymus
adipose tissue
digestive tract
kidneys
gonads
LO7: identify the organs of the endocrine system and other organs containing tissues that secrete hormones in the human body
what is the endocrine system made of?
made up of all the glands, tissues, and cells that secrete hormones
LO7: identify the organs of the endocrine system and other organs containing tissues that secrete hormones in the human body
what are hormones?
chemical messengers transported by the bloodstream and stimulate physiological responses in cells of another tissue or organ
LO8: differentiate b/n endocrine and exocrine glands
what is a gland?
organ that makes one or more substances, such as hormones, digestive juices, sweat, tears, saliva, or milk
LO8: differentiate b/n endocrine and exocrine glands
endocrine glands have what function?
how do endocrine glands secrete their hormones?
intracellular effects –> alter cell metabolism
directly into blood –> ductless
blood capillaries pick up and carry away their hormones
LO8: differentiate b/n endocrine and exocrine glands
exocrine glands have what function?
extracellular effects –> digestion of food
release substances into a duct or opening to the inside or outside of the body
LO8: differentiate b/n endocrine and exocrine glands
pancreas serves as ___ glands in one
it can behave as an ___ or ___
2
exocrine gland
endocrine gland
LO8: differentiate b/n endocrine and exocrine glands
pancreas serves as 2 glands in one:
exocrine gland (describe)
acinar cells –> discharge digestive enzymes into ducts that empty into duodenum
LO8: differentiate b/n endocrine and exocrine glands
pancreas serves as 2 glands in one:
endocrine gland (describe)
islets of Langerhans –> secrete hormones into blood
LO9: indicate similarities b/n the NS and endocrine system
similarities:
1) internal communication
2) function as both NT and H
3) identical effects
4) target cells
4) target cells are receptors
both serve for internal communication – they complement each other
several chemicals function as both NT and H (NOR, dopamine, ADH)
some H and NT produce identical effects on the same organ
only certain target organs or target cells are receptors that respond to NT or H
LO10: describe neuroendocrine (neurosecretory) cells
act like neurons but release hormones into bloodstream
LO10: describe neuroendocrine (neurosecretory) cells
examples of neuroendocrine cells and what they secrete
magnocellular neurosecretory cells –> synthesize oxytocin and vasopressin (ADH)
adenohypophyseal hormone-releasing factors
LO11: describe anatomical relationship b/n hypothalamus and pituitary gland –> hypophysis
what does the hypophyseal portal system link?
what does the hypophyseal portal system regulate?
blood vessels that link hypothalamus and anterior pituitary –> adenohypophysis
regulates mechanism for hypothalamic neuroendocrine regulation of pituitary function
LO11: describe anatomical relationship b/n hypothalamus and pituitary gland –> hypophysis
what connects the hypothalamus and anterior pituitary gland?
hypophyseal portal system
LO11: describe anatomical relationship b/n hypothalamus and pituitary gland –> hypophysis
what does the hypothalamo-hypophyseal tract connect?
hypothalamus and posterior pituitary gland
LO11: describe anatomical relationship b/n hypothalamus and pituitary gland –> hypophysis
what connects the hypothalamus with the posterior pituitary gland?
hypothalamo-hypophyseal tract
LO11: describe anatomical relationship b/n hypothalamus and pituitary gland –> hypophysis
what is the posterior pituitary gland controlled by?
neuroendocrine reflexes
LO11: describe anatomical relationship b/n hypothalamus and pituitary gland –> hypophysis
explain the hypothalami-hypophyseal tract:
the somas of the neuroendocrine cells are located in the ___, more specifically in the ___ nucleus and ___ nucleus
the axons of the neuroendocrine cells pass down the stalk as a bundle and end in the ___ ___ (___)
hypothalamus
paraventricular nucleus
supraoptic nucleus
posterior pituitary (neurohypophysis)
