00:01
So in this question, we're trying to figure out which species would actually have the highest proportion of juxtamedulary nephrons.
00:13
So we're presented with the number of species here.
00:16
So first, let's talk about the juxtamedulary nephrons.
00:19
So if we consider our kidney, remember we have the cortex and the medulla.
00:33
And the juxta medullary nephrons are deep into the medulla.
00:41
So we see this kind of network of nephrons.
00:49
And these are the juxta medullary nephrons.
01:03
And these nephrons are essential for the production of urine when there's a hyper -osmodic situation to body fluids.
01:15
And this is a key adaptation for conserving water in mammal species, especially mammals that occur in a terrestrial environment.
01:25
So remember, hyper -osmodic means that there's more solutes in a solution than an adjacent solution.
01:30
So this type of system allows for water to be extracted from the filterate in the collecting duct.
01:37
And then that results in high concentrations of solutes in the filtrate while retaining water for other essential functions of the body.
01:48
So when we're looking at our options here, we have a river otter, which is obviously near water.
02:02
And so remember we're talking about nephrons that assist with conserving water.
02:08
So we're trying to identify a species that might need the conservation of water.
02:13
Well, a river otter lives in the aquatic environment, so it's probably not going to need this extra sort of assistance with conserving water...