Deep under the Pacific Ocean lie coral reefs colored by some algae that live with corals. Corals usually provide nitrogen (氮) to algae, and in return they get carbon (碳), which gives them energy.
In the early 1980s, a huge heat wave turned more than 90 percent of these corals a pale, lifeless white. And it was believed that about 50 percent of reefs with beautiful corals might disappear by 2030. Heat waves warmed up the same Pacific waters in the late 1990s and again in 2015—2016, but scientists noticed that these heat waves didn’t influence the reefs as badly asthe first. Maybe corals have found a way to adapt (适应).
Swimming to cooler waters is not a good choice for corals, for it makes them easily hurt by the changing climate. But corals are able to adapt. Some turn to those algae that can deal well with heat. Others can use rows of tiny hairs on their bodies to “fan” away too much harmful oxygen (O2) let out by stressed-out algae. Certain baby corals change their own metabolisms (新陈代谢) in order to fight the warming waters. But all these adaptations can protect themselves only to some degree.
After studying and understanding these adaptations, scientists are trying to find ways to help corals fight. If researchers can make corals accept algae that can deal with heat pressure or if they energize genes (基因) that can deal with heat pressure, it will raise the corals’ chance of living through future ocean heat waves.
“When I go down to the sea and see a beautiful healthy reef with these colorful corals, I feel this pleasure of being in this underwater world,” a famous biologist says. “It will be really sad to see it dead. But that does drive you to want to use your skills and your love to help fight.”
41. What can we know from paragraph 1?
A. Corals make algae more colorful.B. Algae provide room for corals to live in.
C. Corals and algae depend on each other.D. Algae produce nitrogen to influence corals.
42. What does the underlined part “the first” in paragraph 2 refer to?
A. The heat wave in the early 1980s.B. The heat wave in the late 1990s.
C. The Pacific waters in 2015—2016.D. The reefs’ disappearance by 2030.
43. What difficulty do corals face?
A.They cannot completely adapt to heat waves.
B. They cannot change their own metabolisms.
C. They have no ability to swim to cooler waters.
D. They have no ability to drive away harmful oxygen.
44. What can we infer from the last paragraph?
A. It’s necessary to live with corals.B. The ocean has become unhealthy.
C. We should try our best to save corals.D. Making a study of the ocean is a must.
45. Which would be the best title for the text?
A. Corals Die OutB. Corals Fight Back
C. Corals Break DownD. Corals Come into Being
