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.
These molecules not only detect oxygen, but help
increase levels of vital red blood cells, which carry oxygen around the body.
Normal mice breathing in air that is 10 percent oxygen—a dangerously low level
similar to conditions at the top of Mount Everest, and about half that of air
at sea level. However, mice that had the oxygen sensor HIF-1a genetically
removed from their skin failed to produce this hormone (荷尔蒙) even after hours of such low oxygen.
These findings, if they hold true in humans, suggest
one could raise the level of oxygen circulating inside the body. This could
help treat lung diseases and disorders such as anemia (贫血症) without injecting drugs, which make up a
multibillion-dollar market, Johnson said.
Athletes also often try to get more oxygen delivered
to their muscles in order to improve their performance. They often do this by
training at high altitudes or in low-oxygen tents. The new study suggests they
might want to expose their skin as well as breathing in low-oxygen air to
improve their performance. “It’s hard to say what exactly might be done,
however—there’s a lot we don’t know yet,” Johnson explained.
The scientists detailed their findings in the April 18
issue of the journal Cell.
1.Which of the following statements is TRUE according
to the passage?
A．It has long
been expected oxygen sensors exist in mice’s skin.
B．People have
to surf the Internet to read detailed findings.
C．It has been
proved that these findings help treat lung diseases.
D．Johnson
believes that Oxygen sensors also exist in human skin.
2.One of the functions of the molecules mentioned
above is _______.
A． increasing
level of oxygen B．improving
athletes’ performance
C．detecting
oxygen D．carrying
oxygen around the body
3.What is Johnson’s attitude to the application of the
findings to the athletes’ training?
A． Hesitating B．Doubting C．Positive D．Negative
4.The best title of the passage may be _______.
A． Humans Might
Sense Oxygen Through Skin
B．Frogs And
Mice Are Distant Relatives
C．First Known
Animal Breathes Through Skin
D．Great
Findings Benefits Athletes A Lot
