MCQs Flashcards
Iron circulates in the blood bound to:
a) Transcobalamin II.
b) Ferritin.
c) Transferrin.
d) Ferroxidase.
e) None of the above.
Transferrin
The splanchnic circulation
a) Includes blood supply to the heart, stomach, liver, spleen and pancreas
b) Is about 750 mls at rest
c) Increases after a meal by the action of functional hyperaemia
d) Is greatly increased throughout the digestive tract by parasympathetic stimulation
e) Is the sole source of blood flow to the liver
Increases after a meal by the action of functional hyperaemia
Which of the following statements about the liver is INCORRECT
a) Secretes hepcidin
b) Acts as a blood reservoir
c) Stores glycogen
d) Breaks down some hormones
e) Stores of most water soluble vitamins
Stores of most water soluble vitamins (it only stores one water soluble vitamin, B12)
Which of the following would NOT be observed in a healthy subject following experimental stretch of the rectum, when the subject does not want to defaecate?
Reflex relaxation of the internal anal sphincter.
Reflex relaxation of the external anal sphincter.
The Valsalva manoeuvre.
Reflex relaxation of pelvic floor muscles.
Straightening of the ano-rectal angle.
The Valsalva manoeuvre
Lipids
a) Excess lipids in the stomach stimulate the secretion of CCK
b) Lipids are metabolised by the brain as an important energy source
c) Chylomicrons are secreted from the small intestine directly into the blood
d) Most dietary triglyceride is stored in the liver
e) Free fatty acids can be taken up by muscle and liver
Free fatty acids can be taken up by muscle and liver
Fibre in the diet has which of the following functions
a) acts as a substrate for gut flora
b) relieves constipation
c) promotes satiety
d) reduces risk of haemorrhoids
e) all of the above
All of the above
Which statement about smooth muscle in the GI tract is INCORRECT
a) The cells are connected to one another by gap junctions
b) Contraction is dependent on Ca2+ - calmodulin within the cell
c) Contraction is not dependant on action potentials
d) Binding of actin and myosin can be blocked by troponin
e) Contraction can be stimulated by a range of stimuli
Binding of actin and myosin can be blocked by troponin
(troponin and myosin)
Which of the following statements regarding the autonomic nerve supply to the gut is INCORRECT?
a) Many sympathetic fibres travel to the gut via the prevertebral ganglia.
b) Autonomic fibres to the lower parts of the gut travel in the pelvic nerves.
c) Parasympathetic fibres synapse once before reaching the gut
d) Postganglionic parasympathetic nerves in the gut release transmitters including Ach and VIP.
e) Sympathetic action on the gut is generally inhibitory
Parasympathetic fibres synapse once before reaching the gut
Stimulation by the parasympathetic nerves:
Is essential for the initiation of gut motility
Causes relaxation of sphincters through the inhibitory post ganglionic fibres
Decreases gastric juice secretion
Increases exocytosis of stored proteins from the acinus cells of the salivary glands
Regulates opening of the external anal sphincter
Causes relaxation of sphincters through the inhibitory post ganglionic fibres
The enteric nervous system:
Can co-ordinate entirely intrinsic reflex activity within the digestive tract
Acts independently of any sensory input from the gut walls
Forms a single plexus lying in the submucosa
Has pacemaker cells which are known to have periodic influx of Na+ to cause a pacemaker potential
Extends from the top of the oesophagus to the rectum
Can co-ordinate entirely intrinsic reflex activity within the digestive tract
The hypothalamus and the pituitary are interconnected
a) by portal vessels carrying GnRH to the anterior pituitary
b) by portal vessels carrying prolactin to the hypothalamus
c) by nerve fibres carrying dopamine to the anterior pituitary
d) all of the above (A-C)
e) two of the above (A and C)
Two of the above (A and C)
(Prolactin acts on breast tissue)
Which is the INCORRECT statement about hormones which bind to intracellular receptors:
a) bind to cytoplasmic receptors associated with heat shock proteins
b) the hormone, receptor and attached heat shock protein pass through the nuclear membrane
c) the hormone causes a change in gene transcription
d) includes thyroid hormones
e) tend to cause relatively long term changes to cell function
The hormone, receptor and attached heat shock protein pass through the nuclear membrane (the heat shock protein does not pass through the nuclear membrane)
Calcitonin
a) is secreted by the C cells of the thyroid gland
b) stimulates the osteoclast activity
c) is an amine hormone
d) secretion is inhibited by gastrin
e) is a hypercalcaemic hormone
is secreted by the C cells of the thyroid gland
Which of the following factors can influence growth?
a) environmental
b) genetic background
c) physiological
d) gender
e) all of the above
All of the above
Which is the INCORRECT statement concerning competitive ELISA assays:
a) An unknown amount of the test hormone is mixed with a known amount of the same hormone which is labelled
b) A single antibody is required for each assay
c) A standard curve is constructed using samples of pure hormone at a range of known concentrations
d) The results can be quantified by, for example, a colour change
e) The higher the hormone concentration in the test sample the greater the colour change
The higher the hormone concentration in the test sample the greater the colour change
Which of the following stimulates food intake?
a) insulin
b) CCK
c) ghrelin
d) GLP-1
e) pancreatic polypeptide
Grehlin
Somatomedins (eg IGF1)
a) are secreted by the anterior pituitary
b) have a half life of a few minutes
c) have a negative feedback effect on the pituitary gland through a long direct feedback loop
d) decrease protein synthesis in the liver
e) trigger fusion of the epiphyses at puberty
trigger fusion of the epiphyses at puberty
The reduced growth that occurs in Achondroplasia is:
a) Is often a result of growth hormone deficiency
b) results in normal body proportions but overall short stature
c) results from deficiency of IGF1
d) commonly occurs in older dogs
e) is caused by a mutation in fibroblast growth factor 3 (FGFR3)
is caused by a mutation in fibroblast growth factor 3 (FGFR3)
db/db mice:
a) have a mutation in the leptin gene
b) are anoretic
c) have low levels of leptin
d) will cause wild type mice to stop feeding if joined in parabiosis experiments
e) tend to be unusually thin
will cause wild type mice to stop feeding if joined in parabiosis experiments
Insulin:
a) is secreted in response to an increase in blood glucose concentrations
b) stimulates the uptake of glucose by GLUT 4 transporters
c) stimulates the conversion of glucose to glycogen in the liver
d) stimulates increased triglyceride synthesis in adipose tissue
e) all of the above
all of the above
The thyroid gland secretes:
a) one hormone
b) two hormones
c) three hormones
d) four hormones
e) five hormones
three hormones
Which of the following is NOT an action of cortisol:
a) increased lipolysis in fat cells
b) increased gluconeogenesis
c) increased triglyceride synthesis
d) increased vascular tone
e) immunosuppression
increased triglyceride synthesis
Which of the following feedback loops best describes the action of cortisol on the hypothalamus?
a) indirect, long
b) direct, long
c) indirect, short
d) direct, short
e) none of the above
indirect, long
The anterior pituitary secretes:
a) thyrotrophin releasing hormone
b) dopamine
c) somatostatin
d) growth hormone
e) antidiuretic hormone
growth hormone