1.非选择题- (共2题)
| O | Si | C | N | H |
地壳 | 48.60 | 26.30 | 0.087 | 0.03 | 0.76 |
细胞 | 65.0 | 极少 | 18.0 | 3.0 | 10.0 |
(1)组成细胞的化学元素在地壳中都普遍存在,没有一种化学元素是细胞所特有的,这一事实说明生物界与非生物界具有__________。
(2)由表中数据可知,同一元素在细胞和地壳中的含量相差甚远,这一事实说明生物界与非生物界具有___________。
(3)在组成活细胞的化学元素中,______的含量最多。
(4)构成生物体的元素有几十种,其中最基本元素是___________________。
(5)构成生物体的元素与自然界中的元素在种类和含量上的关系是______________。

(1)该化合物含有__________个氨基,___________个羧基,形成此化合物的反应称为_____________。
(2)该化合物是由______________个氨基酸组成的,这几个氨基酸形成此化合物时,相对分子质量比原来减少了______________,区分这几个氨基酸不同的基团编号是______________。
(3)该化合物称为______________肽化合物,该化合物彻底水解需要______________个水分子。
(4)鉴定蛋白质所用的试剂是______________;颜色反应为______________。
2.单选题- (共26题)
A.组成生物体的化学元素,可以分成大量元素和微量元素 |
B.组成不同生物体的化学元素不仅种类大体相同含量也基本相同 |
C.组成生物体的化学元素,没有一种是生物界所特有的 |
D.组成玉米和家兔的最基本元素都是碳 |
A.种类差异很大,含量大体相同 | B.种类和含量差异都很大 |
C.种类和含量都是大体相同 | D.种类大体相同,含量差异很大 |
A.浅绿色→棕色→砖红色(沉淀) | B.浅蓝色→棕色→砖红色(沉淀) |
C.棕色→浅蓝色→砖红色(沉淀) | D.棕色→浅绿色→砖红色(沉淀) |
A.斐林试剂(砖红色)、双缩脲试剂(紫色)、苏丹III染液(橘黄色) |
B.双缩脲试剂(紫色)、斐林试剂(砖红色)、苏丹III染液(橘黄色) |
C.苏丹III染液(橘黄色)、双缩脲试剂(紫色)、斐林试剂(砖红色) |
D.斐林试剂(砖红色)、苏丹III染液(橘黄色)、双缩脲试剂(紫色) |
A.甘蔗茎的薄壁组织、甜菜的块根等,都含有较多的蔗糖且近于白色,因此可用于进行可溶性还原糖的鉴定 |
B.花生种子含脂肪多且子叶肥厚,是用于脂肪鉴定的理想材料 |
C.大豆种子蛋白质含量高,是进行蛋白质鉴定的理想植物材料 |
D.鸡蛋清含蛋白质多,是进行蛋白质鉴定的理想动物材料 |

A. 构成上述氨基酸分子的基本元素是C、H、O、N
B. 上述四种氨基酸的R基依次是—H、—CH3、—CH2OH、—CH2COOH
C. R基中可以有氨基或羧基
D. 只要含有氨基和羧基的化合物就是构成蛋白质的氨基酸
A.a+b,40 | B.a,20 |
C.大于a,20 | D.小于a,20 |
A.a是核糖,b则是核酸 | B.a是脱氧核糖,b则是核糖核酸 |
C.a是核糖,b则是核糖核苷酸 | D.a是五碳糖,b则是核糖核苷酸 |
A.甘蔗茎的薄壁组织、甜菜的块根等,都含有较多的糖目接近于白色因此可以用于还原糖的鉴定 |
B.花生种子含脂肪多且子叶肥厚,是用于脂肪鉴定的理想材料 |
C.大豆种子蛋白质含量高,是进行蛋白质鉴定的理想植物组织材料 |
D.鸡蛋清含蛋白质多,是进行蛋白质鉴定的动物材料 |
3.选择题- (共1题)
Although I didn't have any interest in being a school bus driver, I became one. Many years later, I was still working on the school bus. There are so many good reasons. Firstly, the talk brought me different kinds of information. I also got to hear all the family secrets of the newcomers. I have a toy bear who was a great comforter(安慰者) for the little ones. The kids got to look after him on the trip to school and he waited patiently for them to get on for the trip home.
Our bus would often pass a place where we could see some alpacas (羊驼) in front of a farm house. Little Michael would cry excitedly from the seat, “Look, Miss! Look at the camels!” He used to put his head out of the bus window. When I warned him that a little insect would come into his nose if he wasn’t careful, he smartly gave up the habit.
I remember a little girl got on the bus one morning 5 years ago and sobbed(抽泣) all the way to school. We arrived at the school gate. As she waited to get down the bus, she threw her arms around my neck and cried that her grandfather had died the night before.
A school bus driver needs to keep one eye on the road and the other on the mirror to watch what the little ones are doing down the back.
Now, it's important to think how many lives I've been responsible(负责的) for, and how many kilometers I've driven in order to get my passengers home safely during the 20 years. I've enjoyed it, but it’s time to rest and park my school bus.
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【1】题量占比
非选择题:(2道)
单选题:(26道)
选择题:(1道)
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【2】:难度分析
1星难题:0
2星难题:0
3星难题:0
4星难题:0
5星难题:0
6星难题:11
7星难题:0
8星难题:11
9星难题:6