Marine Mammals and Reptiles Flashcards
1
Q
How do Marine mammals excrete waste?
A
Renal excretion with a well developed loop of henle; mammalian skin has a low permeability.
2
Q
How do birds excrete waste?
A
Birds have salt glands to secrete excess salts (as seabirds drink seawater). They also have complex nephrons and extra-renal excretion.
3
Q
How do reptiles excrete waste?
A
A nephron - but no loop of henle
4
Q
Where is the salt gland in snakes?
A
Under tounge
5
Q
Where is the salt gland in iguanas?
A
Nose
6
Q
Where is the salt gland in birds?
A
Nose
7
Q
Where is the salt gland in turtles?
A
Tear ducts (cry tears)
8
Q
How do Salt Glands work?
A
- Cl- is actively transported into the tubule by tubule cells
- Na+ follows due to potential difference (through tight junctions)
- H20 follows into central canal by osmosis - NaCl + H20 = saltwater
9
Q
What is the structure of the salt gland?
A
There are bundles of secretory tubules which all drain into a single central canal, and the central canal drains into the nasal cavity.
