问题 单项选择题

下列有关进化的叙述中,正确的是()

A.任何一个物种都不是单独进化的

B.有利变异的逐代积累是生物进化的实质

C.同一物种的两个不同种群间的地理隔离不会阻碍其基因交流

D.达尔文的自然选择学说奠定了进化论的基础,摒弃了拉马克用进废退和获得性遗传的观点

答案

参考答案:A

解析:

任何一个物种都是和其他物种以及环境共同进化的,A正确。生物进化的实质为基因频率定向改变,B错。地理隔离会阻碍同一物种的两个不同种群间其基因交流,最终可能导致生殖隔离形成不同物种,C错。达尔文的学说接受了拉马克关于器官用进废退和获得性遗传的观点,但他承认变异有的可以遗传,有的不能遗传。在解释适应性的形成时强调自然选择的作用,D错。

考点:本题考查进化相关知识,意在考查考生能理解所学知识的要点,把握知识间的内在联系,形成知识的网络结构能力。

单项选择题
单项选择题

Research on animal intelligence always makes us wonder just how smart humans are. (1) the fruit-fly experiments described by Carl Zimmer in the Science Times. Fruit flies who were taught to be smarter than the average fruit fly (2) to live shorter lives. This suggests that (3) bulbs burn longer, that there is a(n) (4) in not being too bright.

Intelligence, it (5) , is a high-priced option. It takes more upkeep, burns more fuel and is slow (6) the starting line because it depends on learning — a(n) (7) process — instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to (8) .

Is there an adaptive value to (9) intelligence That’s the question behind this new research. Instead of casting a wistful glance (10) at all the species we’ve left in the dust I.Q.-wise, it implicitly asks what the real (11) of our own intelligence might be. This is (12) the mind of every animal we’ve ever met.

Research on animal intelligence also makes us wonder what experiments animals would (13) on humans if they had the chance. Every cat with an owner, (14) , is running a small-scale study in operant conditioning. We believe that (15) animals ran the labs, they would test us to (16) the limits of our patience, our faithfulness, our memory for locations. They would try to decide what intelligence in humans is really (17) , not merely how much of it there is. (18) , they would hope to study a(n) (19) question: Are humans actually aware of the world they live in (20) the results are inconclusive.

2()

A.tended

B.feared

C.happened

D.threatened