【题文】Do you know about bioplastic? It is a kind of plastic, but it is different. Normal plastic is made from chemical materials and takes a very long time to degrade. But bioplastic is quite friendly to the environment. It is made by using bacteria to process natural sources like vegetable oil or sugar, and can break down more easily.

But there is also a problem with bioplastic, despite its advantages concerning environmental protection. The “food” that bacteria eat is also what we humans eat, meaning that bacteria are competing against humans for the same resources.

Recently, scientists have claimed that they have succeeded in finding a new way to produce bioplastic—using two kinds of bacteria and sunlight.

One kind of bacteria is called synthetic cyanobacteria, which can use sunlight to produce sugar. The other kind is Halomonas boliviensis, which lives in the salty waters of Bolivia. It eats the sugar that the first bacteria produce and then produces polymers(聚合物), which are used to create bioplastic. Interestingly, the way the bacteria store polymers is similar to the way humans store fats.

There are a couple of advantages producing bioplastic with these two bacteria, one important advantage being the speed. It is 20 times faster than the normal way we produce bioplastic. Moreover, such method can save a considerable amount of resources. Producing large amounts of bioplastic would commonly require large amounts of com and sugar to feed normal bacteria. It could mean occupation of farmland as well as food supplies. But these two special bacteria can do the same job using nothing but sunlight. The saved land can then be used to grow more food for humans. And according to the scientists, this system doesn’t need rich land or clean water at all, which is quite a bonus.

The next challenge scientists face is that they want to put their lab research into real-world practice. By doing this, bioplastic made with these two bacteria can be widely produced in the future.

【小题1】What does the underlined word “degrade” in the first paragraph probably mean?

A．To break down.	B．To set up.
C．To produce.	D．To digest.

【小题2】The advantages of producing bioplastic with synthetic cyanobacteria and Halomonas boliviensis do NOT include _____.

A．fast production	B．saving land
C．producing polymers	D．saving water

【小题3】What can we infer from the passage?

A．Bioplastic is very friendly to the environment.

B．Bioplastic is made from grain.

C．Bioplastic is not really a kind of plastic.

D．Bioplastic is still not widely used in daily life.

【小题4】What is the author’s purpose in writing the passage?

A．To encourage people to use bioplastic products in daily life.

B．To question the effect of bioplastic on environmental protection.

C．To propose a new method to widely produce bioplastic items.

D．To introduce a new more eco-friendly way of making bioplastic.

Unit 8 Green Living Topic Talk & Lesson 1 Roots and Shoots 随堂检测-2021-2022学年高一英语北师大版（2019）必修第三册