diving mammals Flashcards
How big are diving mammals lungs compared to terrestrial mammals?
Smaller
What happens when whales dive?
Their lungs collapse under the pressure and the air in their alveoli gets forced out into the main airways, where no exchange occurs.
What do seals do before diving tonavoi the bends?
Actively breath out air
Ho does diving mammals blood volume compare to terrestrial mammals?
They have a much greater blood volume compared to body size
Hiow do diving mammals’ RBCs compare to terrestrial mammals?
They have more RBCs, and they may be larger so they can hold more haemoglobin. An increase in RBCs means an increase in viscosity of blood, so, as a component of the “dive reflex” their spleen contracts, forcing more RBCs into general circulation.
How much haemoglobin do diving mammals carry?
50-100% more than man per 100 ml of blood
What is myoglobin?
An oxygen carrying molecule found in muscle cells, diving mammals have a lot more than other mammals
What happens to their heart rate while diving?
It is rapidly reduced, e.g. in seal it goes from 120bpm to 2-4 bpm
What happens to blood flow while diving?
Blood fklo is reduced to all tissues except the brain
What happens to metabolic rate during diving?
It slows down
