1、 （2010·江苏省丰县中学高三期中） A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.
Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.
Now the same oxygen sensors found in frog skins and in the lungs of mammals（哺乳动物）have unexpectedly been discovered in the skin of mice.
“No one had ever looked,” explained Randall Johnson, a biologist researcher.
Mice and frogs are quite distant relatives, so the fact they have these molecules（分子）in common in their skin suggests they might well be found in the skin of other mammals, such as humans.
“We have no reason to think that they are not in the skin of people too,” Johnson said.
