鸟类的尾脂腺、羽毛和角质鳞都是表皮衍生物。()

题型:判断题

问题:

鸟类的尾脂腺、羽毛和角质鳞都是表皮衍生物。()

考点:生物学普通动物学普通动物学题库
题型:判断题

生物技术就像一把双刃剑,它既可以造福人类,也可能在使用不当时给人类带来灾难。例如用克隆技术制造出克隆人,用转基因技术制造生物武器等。面对生物技术可能产生的负面影响,公众不可避免地产生了疑虑。近年来,生物技术引发的社会争论涉及面越来越广。

(1)目前我国是种植转基因作物较多的国家之一,关于转基因生物的安全性的争论越来越多,转基因生物的安全性主要涉及________、____________、_____________等方面。

(2)试管婴儿技术诞生后,继而出现了设计试管婴儿技术,二者在对人类作用上的区别是__________。在技术手段上的区别是___________。

(3)现在大多数人反对设计婴儿性别,其原因是____________。

(4)若克隆人则需要用到下列哪些技术?___________。(填序号)

①.体外培养 ②.体外受精 ③.胚胎移植 ④.核移植

题型:判断题

有助于腰神经根病诊断的一般检查方法是()

A.直腿抬高手法

B.Patrick手法

C.腰部压痛

D.Spurling手法

E.Lhermitte征

题型:判断题

天麻的加工方法为()

A.发汗

B.阴干

C.置沸水中略烫

D.蒸透心,敞开低温干燥

E.置沸水中煮至透心

题型:判断题

Recycling Paper


The process of recycling paper can help to reduce deforestation and energy consumption on a significant scale. There are many different reasons why we should recycle paper products, and some of these are (26) in the paragraphs below.
Energy consumption will always be on the (27) as population levels grow, and so any manufacturing processes which help to reduce energy consumption are (28)
The Energy Information Administration (EIA) claim that there can be as (29) as a 40% energy saving when recycling paper over producing paper (30) the direct raw material.
Although recycling paper has many (31) , it also has its drawbacks. One of these drawbacks is that we cannot recycle the (32) paper product for eternity, as the fibers contained within the paper degrade over time, (33) their strength and length.
On (34) , an individual paper fiber can only be recycled a (35) of six times. Although this is a significant drawback, the six time recycling process will help to (36) a great deal of energy when you consider (37) much paper there is to be recycled.
If paper fibers can be recycled up to 6 times, and we recycled all paper products, this could help to (38) the intensity of deforestation for paper products up to a factor of 6.
With paper production said to (39) around 40% of harvested wood, and paper said to (40) around 90% wood, you can see how recycling paper is an important process for the (41) of our forests.
Today, the use of recycled paper products is on the increase, as more and more people begin to recycle paper (42) products around the home.
Although there are slight differences in the recycling processes of different (43) of paper products (e.g. corrugated, mixed paper, newspaper products), we are able to recycle just about any type of paper product around today.
The recycling logo helps to (44) a recyclable product and can also sometimes help to identify if the product contains any recycled material, in the form of a percentage. This helps a consumer to identify the (45) of recycling various products.

A. purpose B. average C. time D. practice

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