When a dehydrated human patient needs to be given fluids intravenously, he or she is given:
- water, which is hypotonic with respect to body fluids
- saline at a concentration that is isotonic with respect to body fluids
- glucose because it is a non-electrolyte
The sodium ion is at the highest concentration in:
- intracellular fluid
- extracellular fluid
- blood plasma
- none of the above
Cells in a hypertonic solution tend to:
- shrink due to water loss
- swell due to water gain
- stay the same size due to water moving into and out of the cell at the same rate
- none of the above
The macula densa is/are:
- present in the renal medulla.
- dense tissue present in the outer layer of the kidney.
- cells present in the DCT and collecting tubules.
- present in blood capillaries.
The osmolarity of body fluids is maintained at ________.
- 100 mOsm
- 300 mOsm
- 1000 mOsm
- it is not constantly maintained
The gland located at the top of the kidney is the ________ gland.
Active transport of K+ in Malpighian tubules ensures that:
- water follows K+ to make urine
- osmotic balance is maintained between waste matter and bodily fluids
- both a and b
- neither a nor b
Contractile vacuoles in microorganisms:
- exclusively perform an excretory function
- can perform many functions, one of which is excretion of metabolic wastes
- originate from the cell membrane
- both b and c
Flame cells are primitive excretory organs found in ________.
BUN is ________.
- blood urea nitrogen
- blood uric acid nitrogen
- an indicator of blood volume
- an indicator of blood pressure
Human beings accumulate ________ before excreting nitrogenous waste.
- uric acid
Renin is made by ________.
- granular cells of the juxtaglomerular apparatus
- the kidneys
- the nephrons
- All of the above.
Patients with Addison's disease ________.
- retain water
- retain salts
- lose salts and water
- have too much aldosterone
Which hormone elicits the “fight or flight” response?
- anti-diuretic hormone