首页
登录
职称英语
What is the lecture mainly about? [br] Listen to part of the lecture. Then answe
What is the lecture mainly about? [br] Listen to part of the lecture. Then answe
游客
2025-02-04
1
管理
问题
What is the lecture mainly about? [br] Listen to part of the lecture. Then answer the question. Why does the professor say this?
Listen to part of a lecture in a biology class.
Professor:
I’m sure most of you know that we’ve been able to extract certain compounds from plants for use in medicine. Eh, compounds like proteins from some plants can be used in medicines as antibodies in vaccines. And we can even cause some plants to produce certain proteins by incorporating DNA into the plant cells, usually in the leaves. We then extract the proteins to use as antibodies. However, we’ve never been able to produce enough protein to make the process worthwhile. It hasn’t been practical until now.
Now it appears that it’s possible to get a large amount of usable protein from plants. Some researchers have recently succeeded in doing this by using plant seeds to produce these proteins rather than leaves or the other parts of the plant.
Now there are a number of advantages to get protein from plant seeds to produce antibodies. But we have to be sure that these proteins are just as effective as human proteins. And so far the researchers show that antibodies produced from plant seeds protein are effective in humans, which is great. Because typically, antibodies for vaccines and medicines too are produced from micro-organisms like yeasts or bacteria, and it’s a rather complicated process.
OK, so what makes plant seeds good production units? Well, for one thing, there are lots of them, right? One plant can produce a lot of seeds and then there is the issue of storage. Seeds can be stored for long periods of time and the protein retains its effectiveness.
Now that’s not true with other parts of the plant. Leaves for instance, you can’t store them very long, which means you have to get that protein out right away as soon as it’s produced. But using plant seeds as production units allows you to isolate the protein whenever you need it, and you can transport seeds all over the world, even the places where refrigeration might be a problem, not so for yeasts and bacteria, but with seeds, it seems quite possible that we’ll be able to supply vaccine to places that need them. Whereas before this, transporting and preserving these products after a long distance simply wasn’t feasible. And another major benefit of extracting plant proteins for medical use is cost-effectiveness. Unlike the production of proteins for medicinal purpose using yeasts or bacteria like insulin which is a vital protein used in medications, extracting protein from seeds doesn’t require high-tech production labs with all kinds of equipment, and since refrigeration is not crucial for maintenance or transport, it’s just much less expensive to store and maintain plant seeds than other sources of protein. We estimate the total production cost to be 10 to 100 times lower.
选项
A、To remind students of a lab experiment they recently completed
B、To encourage students to provide a summary of a previous lecture
C、To point out something that she thinks the students might not know
D、To use common knowledge to establish a starting point for the lecture
答案
D
解析
讲座一开始教授说的I’m sure most of you know that…表明,这是一个大多人都知道的常识。教授用这个常识是要引出要讨论的内容。可见,D项“运用常识开始讲座”正确。A项“提醒学生最近完成的一次实验”、B项“鼓励学生对上一次讲座内容进行总结”和C项“指出一些她认为学生可能不知道的事情”都没有依据。
转载请注明原文地址:https://tihaiku.com/zcyy/3942053.html
相关试题推荐
Whatisthemainpurposeofthelecture?[br]Whydoestheprofessordiscussthe
Whatisthelecturemainlyabout?[br]Theprofessordiscussestwotypesofflex
Whatisthelecturemainlyabout?[br]Whatcanbeinferredaboutflextime?[ori
Whatisthelecturemainlyabout?[br]Whydoestheprofessormentionschoolsch
Whatisthelecturemainlyabout?[originaltext]Listentopartofalecture
Whatisthelecturemainlyabout?[br]Whydoestheprofessordiscussrefrigerat
Whatisthelecturemainlyabout?[br]Whydoestheprofessormentioninsulin?[
Whatisthelecturemainlyabout?[br]Accordingtotheprofessor,whatdidthe
Whatisthelecturemainlyabout?[originaltext]Listentopartofalecture
Whatarethespeakersmainlydiscussing?[br]Whatdoestheprofessorsayabout
随机试题
[originaltext]W:Ithinkifyouwanttogetsomeexcitementinyourlifeyouou
[originaltext]M:Excuseme,wherecouldIfindrice?W:Theregular-pricedish
[originaltext]W:Oh,whatanuisance!M:Hey,Julia.What’sthematter?Youdon
[originaltext]W:Ijustreadacuriousfact.Didyouknowthatpeoplewhospend
患者,男性,25岁。车祸致脊柱骨折脱位,表现为损伤节段以下痉挛性瘫痪,对侧痛温觉
A.舌色淡红 B.舌质淡白 C.舌质绛红 D.舌质紫黯 E.舌起粗大红刺
2018年1-2月,社会消费品零售总额61082亿元,同比增长9.7%,增速比上
某食品企业为了扩大生产规模,提高市场占有率,经过市场考察决定收购某同类企业。为了
设备基础验收,主要检查验收其()是否符合设计要求。A.外观观感 B.混凝土配
引起流行性脑脊髓膜炎的病原属于( )。A.奈瑟菌属 B.念珠菌属 C.隐球
最新回复
(
0
)