BB EOYS2 Flashcards
describe the structre of rods & cones
outer segment: **photoreceptive part
i) rods contain photopigment called rhodopsin
ii) cones contain photopigment called cone opsins**
* *occur in stacked plates**
inner segment: cell body (& mito)
which anterior pituitary hormone is inhibited by its hypothalamic releasing hormone?
Adrenocorticotrophic hormone (ACTH)
Prolactin (PL)
Lutenising hormone (LH)
Follicle stimulating hormone (FSH)
Thyroid stimulating hormone (TSH)
which anterior pituitary hormone is inhibited by its hypothalamic releasing hormone?
Adrenocorticotrophic hormone (ACTH)
Prolactin (PL): inhibited by prolactin inhbiting factor (e.g. dopamine)
Lutenising hormone (LH)
Follicle stimulating hormone (FSH)
Thyroid stimulating hormone (TSH)
what is the difference in anterior and posterior pituitary development? [1]
what is the difference in anterior and posterior pituitary development? [1]
- *posterior pit** = direct outgrowth of brain (specifically the hypothalamus)
- *anterior pit** = indirect growth: develops from ectoderm in roof of mouth & migrates up
how is baby sucking on a breast an example of creating a neuro-hormonal reflex? [2]
how does oxytocin promote maternal bonding? [2]
baby sucking on a teat:
- sucking action is transmitted to the hypothalamus via spinothalamic tract (neuro)
- releases oyxtocin from posterior pit. (hormonal)
- activates the milk down reflex
how does oxytocin promote maternal bonding? [2]
- suckiling - causes oxytocin release in mothers brain
- this is associated with reward - limbic system
why are anterior pituitary hormones released in ‘two hormone’ mechanism?
- double negative feedback means hormones are released in cyclic fashion (diurnal system or montly cycles)
WORK IN CYCLES !!
which of the following induces targers to produce insulin-like growth factors?
Adrenocorticotrophic hormone (ACTH)
Prolactin (PL)
Lutenising hormone (LH)
Follicle stimulating hormone (FSH)
Thyroid stimulating hormone (TSH)
Growth hormone (GH)
which of the following induces targers to produce insulin-like growth factors?
Adrenocorticotrophic hormone (ACTH)
Prolactin (PL)
Lutenising hormone (LH)
Follicle stimulating hormone (FSH)
Thyroid stimulating hormone (TSH)
Growth hormone (GH)
what is growth hormone (GH) inhibited by? [1]
•Is inhibited by growth hormone inhibiting hormone = somatostatin.
what type of cells make up the conjuctiva? [1]
function? [1]
what type of cells make up the conjuctiva? [1]
stratified columnar epithelium; goblet cells
function? [2]
mucous secreted: mixes with tears to make more viscous
covers sclera & inside of eyelids
explain the caloric stimulation test xx
- warm / cold water is irrigated into extenal auditory canal with a syringe
- creates a convective current in the endolymph of the nearby horizontal semicircular canal
- if warm: mimics a head turn to ipsilateral side (both eyes will turn slowly away from the irrigated ear towards to contralateal ear, then flick occurs towards irrigated ear_
- if cold: mimics head turn to contralateral side: lick occurs away irrigated ear_
COWS: cold flick to other ear; warm: flick to same ear
direction of the flick is called nystagmus
describe the structre of rods & cones
outer segment: **photoreceptive part
i) rods contain photopigment called rhodopsin
ii) cones contain photopigment called cone opsins**
* *occur in stacked plates**
inner segment: cell body (& mito)
spinal accessory nerve comes from which spinal levels? [1]
C1-5
which part of the brain gives you the ability to track an object? [1]
what does ^ connect with?
which pathway mediates neck flexes triggered by seen objects? [1]
which part of the brain gives you the ability to track an object? [1]
superior colliculi
some optic nerve fibres go to the superior colliculi -> connects to the medial longitudinal fasciculi (MLF): links together and synchronises the oculomotor nuclei
which pathway mediates neck flexes triggered by seen objects? [1]
tectospinal tract
= together give synchronised eyes and neck movement
where are most photoreceptors found in the eye? [1]
* which bit of blood circulation can you see in eye using opthalmoscope? [1] *
where are most photoreceptors found in the eye? [1]
fovea
* which bit of blood circulation can you see in eye using opthalmoscope? [1] *
inner circulation
label the borders of the carotid triangle xx
which 3 cells cause seeing stuff x
- *photorceptors** (rods & cones - recive light signal & lose inhibitions) that connect to
- *bipolar** cells that connect to
- *ganglion** cels that send axons to optic nerve
- where do you find thermoreceptors? [2]
- where do you find thermoreceptors? [2]
- *i) cutaneous thermoreceptors
ii) anterior nucleus of hypothalamus: blood temp**
which of the following is released gonadotrophin releasing hormone (GnRH) [2]
Adrenocorticotrophic hormone (ACTH)
Prolactin (PL)
Lutenising hormone (LH)
Follicle stimulating hormone (FSH)
Thyroid stimulating hormone (TSH)
Growth hormone (GH)
which of the following is released gonadotrophin releasing hormone (GnRH) [2]
Adrenocorticotrophic hormone (ACTH)
Prolactin (PL)
Lutenising hormone (LH)
Follicle stimulating hormone (FSH)
Thyroid stimulating hormone (TSH)
Growth hormone (GH)
where is aq humour made in the eye? [1]
ciliary body
how does the hypothalamus regulate water balance?
- where do you find osmoreceptors? [1]
- which hypothalamic nuclei are stimulated to increase water in ur body ? how do they work?
- where do you find osmoreceptors? [1]
- *subfornical organ (wall of third ventricle): detects osmolarity**
- subforrnical organ activates cells in the:
- *i) medial preoptic nucleus**
- this nucleus connects to the limbic system: regulates concious sense of thirst
- *ii) paraventricular nucleus & supraoptic nucleus**
- secrete ADH (makes more aquaporins in CD)
- oxytocin
which nuclei in the hypothalamus do u need to know? [2]
paraventricular nucleus
supraoptic nucleus
where do you find the roots of the cervical plexus? [1]
which nerves are the roots from? [1]
where do you find the roots of the cervical plexus? [1]
around middle posterior border of SCM
which nerves are the roots from? [1]
C1-4
MESS:
- how do supraoptic and paraventricular nuclei release peptides in circulation? [1]
- how does hypothalamic cell bodies from anterior lobe release peptides into circulation? [1]
•Posterior lobe: Hypothalamic cell bodies in the supraoptic and paraventricular nuclei have axons that project down the pituitary stalk to the posterior lobe of the pituitary. They release peptides into the capillaries in the posterior pituitary which circulate in the blood to other organs
•Anterior lobe: Hypothalamic cell bodies have shorter axons that release peptides on to the capillary plexus in the neck of the pituitary stalk
describe the path for when enters light –> occipital lobe xx
ganglion cells in retina have axons that project down optic nerve
two optic nerves meet at the optic chiasm
the axons pass through the optic chiasm and form the optic tract
go to lateral geniculate nucleus and go to occipital lobe
what happens to photoreceptors in the dark? [2]
what happens to photoreceptors in the light? [1]
what happens to photoreceptors in the dark? [1]
constant inward leak of sodium in outerpart of the receptor: keeps the cell depolarised. causes the release of glutamate from its synaptic ending
what happens to photoreceptors in the light? [1]
light hyperpolarises the tonic glutamate release
where do u find the carotid body? [1]
what type of receptors do u find in the carotid body? [1]
whre do u find carotid sinus?
what type of receptors do u find in the carotid sinus? [1]
where do u find the carotid body? [1]
bifurcation of carotid artery (into internal CA & external CA)
what type of receptors do u find in the carotid body? [1]
chemorecptors
whre do u find carotid sinus?
bifurcation of carotid artery (into internal CA & external CA)
what type of receptors do u find in the carotid sinus? [1]
baroreceptors
MESS:
for posterior triangle, what is the
- posterior border
- inferior border
- anterior border
MESS:
for posterior triangle, what is the
- posterior border: SCM
- inferior border: middle 1/3 clavicle
- anterior border: trapezius
describe how eyesight is affected from each lesion
1: partial optic nerve lesion - ipsilateral scotoma = partial blind spot in eye easy to be unaware !
2: complete optic nerve lesion = complete blindess in that eye
3: optic chiasm lesion = bitemporal hemnianopia - cant see in lateral side of both eyes
4: optic tract lesion = homonymous hemianopia - cant see lateral on one side & medial on the other
5: damage to meyers loop = upper left visual field loss
after photoreception has occured, how does signal transduction occur?
light passes through the & meets intercalated discs of rods and cones: glutamate is continously released from synaptic endings of rods and cones onto bipolar cells in the dark
this release is supressed by light
bipolar cells then depolarise & release NTs onto ganglion cells
ganglion cells project their axons into the optic nerve and therefore signal this light sensation to the brain
In the absence of light, the bipolar neurons that connect rods and cones to ganglion cells are continuously and actively inhibited by the rods and cones. Exposure of the retina to light hyperpolarizes the rods and cones and removes their inhibition of bipolar cell
MESS:
what are the borders of the carotid triangle? [3]
the posterior belly of the digastric muscle, the superior belly of the omohyoid muscle, and the anterior border of the SCM.
what are the two subtypes of glaucoma?
how doe drug treatments for glaucoma work?
how do u treat? [5]
open angle glaucoma / type 1: slowly progressive condition. trabecular meshwork becomes gradually blocked. normal angle betweeen cornea and iris
primary angle close glaucoma: occurs when angle between cornea & iris is reduced. flow cannot go into canal of schlemm = rapid increase in pressure. sudden pain and visio n loss
what is each section?
purple:
green:
red
yellow?
what is each section?
purple: digastric
green: submental
red: carotid
yellow: muscular
where do u find the carotid body? [1]
what type of receptors do u find in the carotid body? [1]
whre do u find carotid sinus?
what type of receptors do u find in the carotid sinus? [1]
where do u find the carotid body? [1]
bifurcation of carotid artery (into internal CA & external CA)
what type of receptors do u find in the carotid body? [1]
chemorecptors
whre do u find carotid sinus?
bifurcation of carotid artery (into internal CA & external CA)
what type of receptors do u find in the carotid sinus? [1]
baroreceptors
what makes up the posterior triangle of neck?
- posterior border? [1]
- anterior border? [1]
- other border? lol [1]
what important structures run through it? [4]
what makes up the posterior triangle of neck? [3]
- posterior border: sternocloidomastoid
- anterior border: trapezius
- other border: middle 1/3 clavicle
what important structures run through it? [4]
- *- spinal accessory nerve (CN XI)** comes out of it and **innervates the trapezius
- external jugular vein
- brachail plexus (in inferior section)
- part of subclavian**
describe the mechanism of HPA axis (hypothalamus-pit-adrenal axis)
describe the mechanism of HPA axis (hypothalamus-pit-adrenal axis):
- Cells in hypothalamus release CRH (Corticotropin releasing hormone)
- CRH acts on anterior pit to releease ACTH (adrenocorticotropic hormone)
- ACTH acts on adrenal cortex to release cortisol
- *BUT: negative feedback system:**
- cortisol inhbits release of above
objects in left visual field go to which visual cortex? [1] in right and left eye?
describe the pathway info goes if looking at something in left visual field from right and left eye?
left visual field –> right visual cortex (& vice versa)
if seeing something in the left visual field:
left eye
pass through lens & stimulate the photoreceptors in nasal hemiretina in left eye. ganglion cell axons project out of optic nerve & cross over in optic chiasm; end up synapsing on lateral geniculate nucleus on right hand side
right eye
left visual field stimulates temporal hemiretina & stays on same side in optic chiasm go to lateral **geniculate nucleus on right hand side
both then go to right visual cortex**
vestibulo-ocular reflex - what does this allow? [1]
which is the afferent CN? [1]
which is the efferent CN? [2]
vestibulo-ocular reflex - what does this allow? [1]
head changes angle, eyes compensate for movement & keep gaze steady
which is the afferent CN? [1]
vestibulo-cochlear (VN III)
which is the efferent CN? [1]
**abducens (CN VI): drives the lateral rectus muscle
CN III: drives the medial rectus muscle
mediated by: medial longitudinl fasiculus**
what would you see / not see in 6-8?
- optic radation lesion: homonymous hemianopia with foveal sparing - there is macula sparing bc of axons on other side of brain
7 visual cortex lesion in inner cortex: homonymous hemianopia (very similar to above)
8: visual cortex lesion in superfial striate cortex (central area 17): bilateral loss of macula vison
describe how eyesight is affected from each lesion
1: partial optic nerve lesion - ipsilateral scotoma = partial blind spot in eye easy to be unaware !
2: complete optic nerve lesion = complete blindess in that eye
3: optic chiasm lesion = bitemporal hemnianopia - cant see in lateral side of both eyes
4: optic tract lesion = homonymous hemianopia - cant see lateral on one side & medial on the other
5: damage to meyers loop = upper left visual field loss
what is each section?
purple:
green:
red
yellow?
what is each section?
purple: digastric
green: submental
red: carotid
yellow: muscular
