下列哪一项不是拉马克的观点() A.生物的种类是随着时间的推移而变化的 B.生物

题型:单项选择题

问题:

下列哪一项不是拉马克的观点()

A.生物的种类是随着时间的推移而变化的

B.生物的某一器官发达与否取决于用与不用

C.生物的种类从古到今是一样的

D.环境的变化使生物出现新的性状,并且将这些性状传给后代

考点:高中生物生物的进化生物的进化题库
题型:单项选择题

下列关于原子的说法错误的是[ ]

A.原子是化学变化中的最小微粒

B.原子在不断地运动

C.有些物质是由原子直接构成的

D.原子是不可再分的微粒

题型:单项选择题

干烤法杀灭芽孢的条件是 ()

A.箱温80~100℃,时间10分钟

B.箱温120~140℃,时间15分钟

C.箱温160~170℃,时间40~50分钟

D.箱温150℃,时间60分钟

E.箱温180℃,时间20~30分钟

题型:单项选择题

用重铬酸钾标定硫代硫酸钠溶液时,以下操作步骤中,错误的是()

A.称取烘至恒重的基准级重铬酸钾,置于碘量瓶中,加纯水溶解

B.加定量的硫酸,盖塞

C.加定量的碘化钾溶液,立即用硫代硫酸钠滴定

D.滴定至溶液颜色变为淡黄色,加入淀粉指示剂

E.继续滴定至蓝色转变为亮绿色

题型:单项选择题

沉浸虚拟现实的设备常见的有()。

A.立体头盔显示器

B.位置跟踪器

C.数据手套

D.三维鼠标

题型:单项选择题

The first 50 years of the next millennium will be critical for the world’s population. By 2050 population growth should have leveled off, but by then we’ll have 10 billion people -- two-thirds as many again as we have today. The rate of population growth is something we can choose right now, though it’s not something that just happens, but a matter of human choice. The choice is a complicated one, with many variables, but it remains a choice.
If we want to prevent a population explosion, we should take action now -- or assist the poorer countries to do so. They need better government, better institutions, better labor and capital markets, better schools.
Anything that increases the value of women’s time and adds to the cost of caring for a child makes a woman less likely to have that child. Since big families are often seen as safety nets for illness and old age, improving poor people’s access to insurance, pensions and welfare institutions also has a major impact. This can be as simple as rural credit, providing a means of saving. Finally, there is education -- both for women and, perhaps even more important, for the next generation of children.
These steps are there to be taken, but there appear to be some countries that are not seriously trying at the moment. If we cannot achieve that we will certainly not control population.
That said, I don’t feel pessimistic that we are going to run out of resources: we are becoming more efficient at producing food faster than the rate at which population is increasing. There is, however, a risk that we will wreck the environment so effectively that the world will no longer be an attractive place to live. That really would be a dismal outcome, to reach world population equilibrium only to find we’d destroyed the natural environment in the process.

The author is more worried about the ______.

A.shortage of food in the future

B.illiteracy of the people

C.welfare of the poor people who have more children

D.the damage of the surroundings in which we live

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