Most mammals have two lungs, and a diaphragm. The diaphragm pulls downward the lungs, which suck air in (much like a vacuum), and the diaphragm then pushes upward on the lungs, to exhale (breathe out) carbon dioxide.
Most get it from the dissolved oxygen in the water through their gills. Others, such as sea mammals, dolphins etc, need to surface to breathe
killer whales are mammals but they can not live on land beacause they are to big and can not walk with flippers.
Mammals need oxygen to breathe. Oxygen is a gas that is in the air. Without oxygen, mammals cannot live long.
land mammals live on land, sea mammals live in the water.
because it has the type of things they need for their health and oxygen to breath through their gills they are not mammals and can not breath on land like we can so in order for it to live it must live in water.
Mammals evolved on land, and most still live on land. However, there are still a number that live exclusively in the water (such as whales, dolphins, manatees, etc) and many more that spend much of their time in water (such as beavers, seals, platypus, etc). One thing to note about aquatic mammals is they cannot get oxygen from water like fish, so they have to surface to breathe air frequently.
because they cannot live out of the water and yes they are mammals!!
Aquatic mammals are mammals that can swim and live in water if necessary.
whales
no
Yes, mammals like Manatee, dugong, whales and dolphins all live in salt water.
By swimming to the surface - like dolphins do! :)