16/04/18 Flashcards
What attaches to the crista galli?
falx cerebri
What lies superior to the corpus callosum?
cingulate gyrus
What is the net yield of glycolysis?
2NADH and 2 ATP
What is the first step of glycolysis?
glucose to glucose-6-phosphate
What enzyme carries out the first step of glycolysis?
hexokinase
where is the isoenzyme of hexokinase, glucokinase found?
in thel iver
What enzyme does ATP allosterically inhibit?
phosphofuctokinase
Where is glycogen mainly stored in the body?
liver, to a lesser extent, muscles
What enzyme breaks down gylcogen?
glycogen phosphorylase
How many molecules of ATP does one hydrogen molecule produce?
3- each hydrogen pair reduces one atom of oxygen releasing 3 molecules of ATP
What gives the brain energy ?
glucose
Where does oxidation of fatty acids take place in the cell?
mitochondria
What coenzyme is produced by the beta-oxidation of fatty acids?
acetyl coA
Where is arachiodonic acid foudn in the cell?
attached to the cell membrane phospholipids by esterification
What enzyme can release arachiodonic acid from the cell membrane?
phospholipase A2
Give an example of a double stranded RNA virus?
rotavirus
What is BRCA2?
DNA repair protein
What is the function of pRb?
tumour suppressor proetin that inhibits cells from entering the S phase
What type of protein are Ras proteins?
proto-oncogenes- regulatino of cell signalling
What is the function of Myc?
transcription factor which facilitates the progression of the cell cyle- proto-oncogene
What is the precursor of oestrodiol?
testosterone
What is seen on serum biochemistry with osetopetrosis?
all normal
What enzyme is the rate-limiting factor in glycolysis?
phosphofructokinase
What does the trilaminar disc consist of?
ectoderm; endoderm; mesoderm
When does the trilaminar disc form?
3rd week of development
How many pharyngeal arches are ther?
6 but the 5th arch regresses
What germ cell layer do the pharyngeal arches dervide from?
mesoderm
What germ cell layer does the urogenital system develop from?
mesoderm
What does the renal system develop from?
nephrogenic cord- metanephros
What is amniotic fluid formed from before keratinisation?
fluid passing across fetal skin
When do the kidneys start functioning the fetus?
week 12
What is hte main protein in amniotic fluid?
albumin
What is a low sperm count defined as?
<15 million/ml
What is compaction in emrbyology?
stage of cell diviosn wehn the cell flattens out and it becomes impossible to determine cell outlines- leads to formation of the morula
What is produced from the ectoderm?
nervous system and skin epidermis
What germ cell layer does the GI tract derive from?
endoderm
What cells give rise to the chorionic villi?
extraembyronic mesoderm
Apart from the nervous system, whwat else does the neural crest give rise to?
melanocytes
What is the function of hte primitive streak?
determiens symmetry of the developing embryo
What is clitoris formed from?
genital tubercle
Which sex do the gonads form from the paramesonephric ducts?
female
What is the ligamentum venosum a remnant of?
ductus venosus
What is the function of hte vitelline veins?
take blood away form the yolk sac
What is the correlation between the thyroid and hyperemesis gravidarum?
associated with high levels of free T3 and T4 and reduced TSH
What may there be a decrease in TSH in the first trimester?
beta-HCG has thyrotrophic activty leading to increase thyroid activity and negative feedback on hypiothalamus
What cells produce PTH?
chief cells of the parathyroid glands
Why may prolactin be increase in priamry hypothyroidism?
release in reposne to TRH- which is increase in hypothyroidism
What is seen with PRL levels following an epileptic seizure?
can be raised
Where does the isthmus lie in realtion to the tracheal rings?
anterior the tracheal rings 2-4
What is the majority of cortisol bound to in plasma?
cortisol-binding globulin
Where is renin secreted from?
juxtaglomerular cells of the macuka densa of the kidney
What is Waterhouse-Friderichsen syndrome?
haemorrhage into the adrenal cortex as a result of fulminant meningococcaemia
What is the main oestrogen postmenopause?
oestrone