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问题 选择题

读下图，“理想大陆”自然带分布图，它表示的是排除山地、高原等地形因素后的大陆自然带分布状况。读图回答题。

小题1:AB沿线自然带更替的主导因素是 (    )

A．热量

B．光照

C．水分

D．地形小题2:图中北半球的亚寒带针叶林带在大陆东部比西部的纬度位置低些，原因主要是(      )

A．大陆西部受到寒流影响

B．大陆西部受到地势影响

C．大陆东部受到暖流影响

D．大陆东部受到寒流影响

答案

小题1:C

小题2:D

题目分析：

小题1:根据图示AB位于中纬度地区，由沿海到内陆的自然带更替，故判断属于干湿度地带性，是由于从沿海到内陆的水分条件的递变而形成的。

小题2:北半球的亚寒带针叶林带在大陆东部比西部的纬度位置低些，说明该纬度的大陆东岸气温较大陆西岸低，结合影响气温的主要因素：纬度位置、地形和洋流等因素分析，该纬度的大陆东岸受寒流影响，降温减湿，而大陆西岸受暖流影响，增温增湿。

点评：本题难度一般，属于主干知识的常规考点，学生只要能抓住图示的自然带递变规律，并能结合影响气温的主要因素等内容综合分析即可。

选择题

More attention should be _____ to the rainforest where I live. [ ]

A. made

B. paid

C. taken

D. sent

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填空题

Seasick Try Controlling Your Breathing


If you get seasick easily, you may prepare for boat rides with pressure-point bracelets, ginger, or a prescription skin patch. (1) The technique presumably works because it helps control gravity sensors in the abdomen-a lesser-known input to our fine-tuned balance system.
(2) The inner ears sense motions of the head; the eyes see where the head is; and tiny sensory organs in muscles and tendons sense where the rest of the body is. More recently, researchers have realized that sensors in many other parts of the body also play a role: in the abdomen, the lower organs, and even blood vessels. (3) But if one or two don’t match up, the brain gets confused and we become nauseated.
Scientists knew the most sickening motions closely match the rate of natural breathing; they also knew that people naturally tend to breathe in time with a motion. (4)
Researchers from Imperial College London enlisted 26 volunteers to sit in a tilting, rocking flight simulator and coordinate their breathing in various ways with the motion. (5) The natural tendency was for volunteers to inhale on every backward tilt, in rhythm with the rocking. (6) They felt even better if they breathed slightly faster or slower than the cyclic heaving of the chair; using that technique, the time until onset of nausea was 50% longer than during normal breathing.
(7) Abdominal sensors are known to send motion signals to the brain more slowly than those in the inner ear because they’re farther away from the brain and because abdominal organs have more mass, which means they resist movement a tiny bit longer. (8) But if the diaphragm opposes gravity-induced stomach motions with controlled breaths, there is less sensory conflict and less nausea. "This technique is very good for mild everyday challenges," says medical research scientist Michael Gresty, a member of the study team. "it’s completely safe, and it’s not a drug."
A. But if the subjects exhaled on every backward tilt, they didn’t get sick as quickly.
B. As long as all of these sensors send matching signals to the brain, we feel oriented.
C. Now there’s one more remedy: timing your breathing to counteract the nauseating motion.
D. So why do these tactics work
E. The brain is traditionally thought to sense body position in three ways.
F. The time lag between the two types of sensors creates a mismatch that builds up in the brain and makes us gradually sicker, the researchers say.
G. The tests lasted up to 30 minutes, or until subjects felt moderately sick.
H. But no one had ever tested whether breathing out of time with a motion could prevent nausea.
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