题目

蚯蚓的体节中有一生殖带，其位置为（    ） A、靠近前端       B、靠近后端     C、位于中部       D、位置不确定 答案：B 【解析】 试题分析：蚯蚓是雌雄同体，异体受精。性成熟的个体，第14－16体节色暗肿胀，无节间沟，无刚毛，腹面有刚毛，如戒指状，称为生殖带或环带。生殖带的形态和位置，因属不同而异。生殖带的上皮为腺质上皮，其分泌物在生殖时期可形成卵茧。生殖带的第一节即第14体节腹面中央，有一雌 Paper was first made in the year 105. It was made by a Chinese named Cai Lun. People in Japan learned of paper around the year 600. As years went by， people in other places began to make paper. The lead(铅) pencil is not made of lead. It is made of graphite(石墨). People found graphite in 1564. They thought it was a kind of lead. Today we still call pencils “lead pencils”. The first pencils were made by putting strings(线) around sticks of graphite. The first wooden pencils were made by Kasper Faber from Germany in 1761. Erasers like those we use today were first made in France by a man named Magellan in 1752. It was Hyman L. Lipman who first put eraser on the ends of pencils. And that is how the pencils come to be. 1.How many years earlier was paper made in China than in Japan?A. About 100 years. B. About 400 years. C. More than 500 years. D. 495 years.2.Germans made paper____________.A. earlier than JapanB. later than Japan C. as early as Japan D. as late as Japan 3.At first pencils were made of __________. A. wood B. Lead C. sticks D. string and graphite4.Kasper Faber was ___________.A. an Englishman B. a Frenchman C. a German D. an American5.Which of the following statements is NOT true? A. Paper was first made in China. B. Graphite isn’t a kind of lead.C. The first wooden pencils were made in Germany.D. Hyman L. Lipman made the first erasers.