Anatomy Flashcards
what is the diencephalon
posterior part of the forebrain, forms central core of cerebrum
what does the diencephalon consist of
the thalamus and hypothalamus
what is the pituitary gland connected to
the hypothalamus
what connects the hypothalamus and the pituitary gland
the infundibulum
what is another name for the infundibulum
pituitary stalk
name the 3 main parts of the anterior lobe of the pituitary gland
- pars distalis
- pars tuberalis
- pars intermedia
what is another name for the anterior lobe of the pituitary gland
adenohypophysis
what is the anterior pituitary formed from embryonically
from an upgrowth of rathkes pouch
role of the anterior pituitary
responsible for the synthesis and release of most pituitary hormones
name the trophic hormones produced in the anterior pituitary (4)
TSH, ACTH, FSH, LH
what does it mean if a hormone is trophic
they stimulate other endocrine glands to produce their particular hormones
name the non-trophic hormones produced by the anterior pituitary (2)
GH and prolactin
what cells are found in the anterior pituitary
chromophils
what is another name for the posterior pituitary
neurohypophysis
what is the main segment of the posterior pituitary called
pars nervosa
embryological origin of the posterior pituitary
outpouching of the third ventricular floor, derived from neuroectoderm
where is oxytocin synthesised
hypothalamus
role of the posterior pituitary
storage and release of ADH and oxytoxin
histology of the posterior pituitary
modified glial cells and axonal processes
what chemical class of hormone is GH
protein
what chemical class of hormone is prolactin
peptide
what chemical class of hormone is TSH
glycoprotein
what is ACTH
adrenocorticotropic hormone
what chemical class of hormone is ACTH
peptide
what chemical class of hormone is FSH
glycoprotein
what chemical class of hormone is LH
glycoprotein
what chemical class of hormone is ADH
peptide
what chemical class of hormone is oxytocin
peptide
effect of GH
promotes growth of body tissues
effect of prolactin
promotes milk production from mammary glands
effect of TSH
stimulates thyroid hormone release from thyroid
effect of ATCH
stimulates hormone release by adrenal cortex
effect of FSH
stimulates gamete production in gonads
effect of LH
stimulates androgen production by gonads
effect of ADH
stimulates water reabsorption by kidneys
effect of oxytocin
stimulates uterine contractions during childbirth
role of hypophyseal portal veins
transport hypothalamic hormones to anterior pituitary
where is the pituitary gland located
in the pituitary fossa of the sphenoid bone
what is another name for the pituitary fossa
sella turcica
what lies directly above the pituitary gland
the optic chiasm
what lies anterior to the pituitary gland
sphenoid sinus
which artery lies posteriorly to the pituitary gland
basilar artery
what forms the optic chiasm
right and left optic nerves crossing over
how to we usually gain access to the pituitary fossa
transsphenoidal approach
clinical sign of damage to the optic chiasma
bitemporal hemianopia
clinical signs of damage to the oculomotor nerve during pituitary surgery (2)
eye movement deficits
dilated pupil
clinical sign of damage to the trochlear nerve during pituitary surgery
difficulty looking inferiorly and laterally
clinical signs of damage to the trigeminal nerve during pituitary surgery (2)
paraesthesia of face
difficulty swallowing
clinical sign of damage to the abducent nerve during pituitary surgery
difficulty abducting eye
clinical sign of damage to the cavernous sinus during pituitary surgery
venous haemorrhage
clinical sign of damage to the internal carotid artery during pituitary surgery
catastrophic haemorrhage
clinical sign of damage to the dura mater during pituitary surgery
CSF leak
what are dural venous sinuses
venous channels in the dura mater that drain most of the venous blood from the cranial cavity into internal jugular veins
how many venous sinuses do we have
11
venous sinuses found on either side of the sella turcica and what they drain
cavernous sinus drains the ophthalmic veins
what is the diaphragma sella
tough sheet of dura mata forming roof (diaphragm) over pituitary fossa
what is the tentorium cerebelli
tough sheet of dura mater ‘tenting’ over cerebellum in posterior cranial fossa but with central gap
why does the tentorium cerebelli contain a central gap
to allow the brainstem to pass through it
where does the temporal lobe of the brain lie
in the middle cranial fossa
where are the platysma muscles located
immediately deep to the skin within the superficial fascia of the neck
what group of muscles do the platysma muscles belong to
muscles of facial expression
innervation of the platysma muscles
facial nerve
what are the carotid sheaths
tube-like bilateral compartments of deep fascia
where do carotid sheaths attach to
superiorly to the base of the skull
where are the carotid sheaths located
anterolaterally in the neck posterolateral to the thyroid gland
deep to investing fascia
how many strap muscles do we have
4
what is the thyrohyoid muscle innervated by
C1 which travels within the hypoglossal nerve
what are the majority of the strap muscles innervated by
ansa cervicalis of the cervical plexus
where does the ansa cervicalis arise from
anterior rami of C1-3
when during development does the thyroid gland reach its final position
7th week
when does thyroid gland start to develop
4th week of embryogenesis
what is caused by the failure of descent of the thyroid
lingual thyroid
what is caused by excessive descent of the thyroid gland
retrosternal location in the mediastinum
what is caused by the failure of regression of the thyroglossal duct
thyroglossal duct cyst
what does the thyroid gland consist of
2 lateral lobes connected by the isthmus
where does the isthmus lie
anterior to the 2nd and 3rd cartilages of the trachea
where do the thyroid lobes attach
to the lateral aspects of the thyroid and cricoid cartilages and the trachea
how to differentiate a thyroid lump
will move superiorly then inferiorly with the larynx during swallowing
how many parathyroid glands do we have
4
where are the parathyroid glands located
on the posterior surfaces of the lateral lobes of the thyroid gland
what is the pyramidal lobe
remnant of the thyroglossal duct
where does the pyramidal lobe of the thyroid gland most commonly originate from
the left lateral lobe
arterial supply of the thyroid gland
superior and inferior thyroid artery
where does the superior thyroid artery arise from
as the first branch of the external carotid artery
where does the inferior thyroid artery arise from
the thyrocervical trunk (branch of the subclavian artery)
venous drainage of the thyroid
superior, middle and inferior thyroid veins which form a venous plexus around the thyroid gland
where do the superior and middle thyroid veins drain into
the internal jugular vein
where does the inferior thyroid vein drain into
the brachiocephalic vein
parasympathetic nervous supply to the thyroid
vagus nerve
sympathetic nervous supply to the thyroid
superior, middle and inferior ganglia of the sympathetic trunk
lymphatic drainage of the thyroid gland
to the paratracheal and deep cervical nodes
where is the thyroid gland located in relation to fasia
in the pretrachial fascia
what sits anteriorly to the thyroid
strap muscles
what sits laterally to the thyroid
carotid sheath
what sits medially to the thyroid
trachea and oesophagus, external and recurrent laryngeal nerves
what nerve can be damaged during thyroid surgery
recurrent laryngeal nerves
how much do adrenal glands usually weigh
4-5g each
location of the adrenal glands
superior to the upper pole of the kidneys, retroperitoneal
what separates the kidneys and adrenal glands
a fascial septum
state the basic composition of the adrenal gland
outer cortex and central medulla
arterial supply to the adrenal glands
superior, middle and inferior suprarenal arteries
venous drainage of the adrenal glands
right adrenal vein -> inferior vena cava
left adrenal vein -> right adrenal vein -> inferior vena cava
name the 3 main layers of the adrenal cortex
- zona glomerulosa
- zona fasciculata
- zona reticularis
primary role of the zona glomerulosa
producing mineralocorticoids e.g. aldosterone
primary role of the zona fasciculata
production of glucocorticoids e.g. cortisol
primary role of the zona reticularis
produce adrenal androgens e.g. DHEA
what are the important cells found in the adrenal medulla
chromaffin cells
role of chromaffin cells in the adrenal medulla
secrete catecholamines e.g. adrenaline and noradrenaline
what controls the secretion of catecholamines
sympathetic nervous system
name the 3 secretory cells in the endocrine pancreas
alpha cells, beta cells, delta cells
role of a cells in the endocrine pancreas
secrete glucagon which acts to increase blood glucose levels
role of b cells in the endocrine pancreas
secrete insulin which acts facilitate the uptake of glucose into body cells
role of d cells in the endocrine pancreas
secrete somatostatin which inhibits the exocrine, endocrine and CNS systems
what is the primary female sex organ
the ovary
what hormones does the ovary secrete
oestrogen and progesterone
