Bio 112 Ch 44
excrete more water molecules than taken in, because of the high load of ion ingestion
A human who has no access to fresh water but is forced to drink seawater instead will _____.
they operate an extensive set of active-transport ion pumps
A primary reason that the kidneys have one of the highest metabolic rates of all body organs is that _____.
selective reabsorption
Materials are returned to the blood from the filtrate by which of the following processes?
ammonia
One of the waste products that accumulates during cellular functions is carbon dioxide. It is removed via the respiratory system. What is another waste product that accumulates during normal physiological functions in vertebrates?
urea is less toxic than ammonia
The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that _____.
the concentration gradient; ATP
The force driving simple diffusion is _____, while the energy source for active transport is _____.
differential permeabilities of ascending and descending limbs of the loop of Henle are important in establishing an osmotic gradient
The loop of Henle dips into the renal cortex. This is an important feature of osmoregulation in terrestrial vertebrates because _____.
excrete large quantities of water
To maintain homeostasis freshwater fish must _____.
the primary nitrogenous waste product of humans
Urea is _____.
liver from NH3 and carbon dioxide
Urea is produced in the _____.
the precise control of the retention of water and electrolytes
What is the function of the osmotic gradient found in the kidney? The osmotic gradient allows for _____.
The renal artery delivers blood with nitrogenous waste to the kidney and the renal vein brings blood with less nitrogenous wastes away from the kidneys.
Why are the renal artery and vein critical to the process of osmoregulation in vertebrates?