MDS PREP
What are the two major functions of GH?
1) Stimulation of growth hormone-dependent lipolysis and glycogenolysis
2) Stimulation of gluconeogenesis and growth of the skeletal system
3) Stimulation of cortisol synthesis and thyroid hormone release
4) Regulation of insulin secretion and cardiovascular function
Answer: 2) The two major functions of GH are the growth of the skeletal system and metabolic effects, including gluconeogenesis.
What is the condition characterized by the lack of intrinsic factor, leading to vitamin B12 malabsorption?
1) Pernicious anemia
2) Celiac disease
3) Lactose intolerance
4) Crohn's disease
Physiology
Answer: 1
Pernicious anemia is caused by the lack of intrinsic factor, which leads to impaired vitamin B12 absorption and subsequent megaloblastic anemia.
What is the primary mechanism of action of the Na+/I+ symporter in thyroid cells?
1) Primary active transport
2) Facilitated diffusion
3) Secondary active transport
4) Osmosis
The Na+/I+ symporter (NIS) in thyroid cells uses the energy from the electrochemical gradient of sodium to actively transport iodide into the cells, which is an example of secondary active transport.
What is the main function of the sodium-potassium-chloride cotransporter in the thick ascending limb of the loop of Henle?
1) To reabsorb sodium and chloride
2) To reabsorb sodium and potassium
3) To reabsorb sodium and secrete hydrogen
4) To reabsorb sodium, potassium, and chloride
E) To reabsorb sodium and hydrogen carbonate
The sodium-potassium-2-chloride (Na+-K+-2Cl-) cotransporter in the thick ascending limb of the loop of Henle is responsible for reabsorbing sodium and chloride ions from the tubular fluid into the blood. This process helps in the maintenance of osmotic balance and the generation of the medullary interstitial gradient.
What is the primary mechanism of sodium reabsorption in the distal convoluted tubule and collecting ducts?
1) Passive diffusion
2) Active transport with sodium-potassium ATPase pump
3) Facilitated diffusion
4) Countercurrent exchange with hydrogen ions
The primary mechanism of sodium reabsorption in the distal convoluted tubule and collecting ducts is active transport with the sodium-potassium ATPase pump.
Most of the pre ganglionic sympathetic fibres are
1 A fibres
2 B fibres
3 C Fibres
4 None of the above
Physiology
Answer: 2
- A fibres are myelinated fibres having fastest rate of conduction
Which of the following structures is associated with the control of voluntary eye movement?
1) Occipital lobe
2) Temporal lobe
3) Frontal eye field
4) Parietal lobe
The frontal eye field, located in the dorsolateral part of the frontal lobe, is involved in the control of voluntary eye movement. It is part of the motor system and helps in the planning and execution of saccadic movements.
The osmolarity of the tubular fluid in the medullary collecting duct is primarily controlled by which hormone?
1) Aldosterone
2) Atrial Natriuretic Peptide (ANP)
3) Antidiuretic Hormone (ADH)
4) Renin
The osmolarity of the tubular fluid in the medullary collecting duct is primarily controlled by Antidiuretic Hormone (ADH), which increases water reabsorption.