A-Level课程证书被几乎所有英语授课的大学作为招收新生的入学标准。这门课程的重要性可想而知,那么Alevel生物考试中的知识点,同学们都有哪些了解?今天小编就为大家带来相关的知识介绍,希望能够帮助大家更好的应对考试。
A starch is a complex polysaccharide made up of a large number of glucose as monomeric units joined together by glycosidic bonds.
Starch(淀粉): 是葡萄糖分子聚合而成的,它是细胞中碳水化合物最普遍的储藏形式。
Starch is long chains of sugar molecules linked together like a chain. A single sugar molecule is a monosaccharide.
淀粉是由葡萄糖分子链接而成的长链。一个葡萄糖分子被称为单糖。
Many sugar molecules linked together is a polysaccharide.
Starch, therefore, is a polysaccharide.
有很多葡萄糖分子连接而成的糖被称为多糖,淀粉也是多糖。
Chemical Formula of Starch:
Starch is a chain of glucose molecules, but the chain isn't always straight. Sometimes, the sugar molecules branch off from the main chain and form their own, just like a tree has a main trunk and then branches. As such, starch actually has two forms: one form has no branches while the other form does.
淀粉是葡萄糖分子链构成的长链,但是长链不是总是直的,它也有很多支链就像树一样。淀粉一般有两种形式:支链淀粉和直链淀粉,我们来看一下到底有什么区别?
The branchless form is amylose.(直链淀粉)
Amylose is an unbranched chain of glucose molecules joined by 1, 4 glycosidic bonds, as a result of that amylose is coiled and thus it is very compact molecule meaning it can store a lot of energy.
The branched form is Amylopectin.(支链淀粉)
Amylopectin is branched and is made up of glucose molecules joined by 1, 4 and 1,6 glycosidic bonds, due to the presence of many side branches it is rapidly digested by enzymes therefore energy is released quickly. It is also a compact molecule.
以上就是小编为大家带来的关于Alevel生物课程的相关内容,希望能够帮助大家,在备考中要多刷题,在从错题中找到错的原因,进行总结和分析,避免下次犯同样的错误。想要获取更多英国大学对Alevel物理考试等更多信息,大家可以线上咨询客服哦!最后小编预祝大家能考取心中满意成绩。
Alevel课程包含70多门可供学生选择,要比国内科目内容更广,最常见的就是:数学、进阶数学、物理、化学、生物、经济学等基础性科目,这些也是中国学生在Alevel选课时选择最多的科目。