甘肃省酒泉市玉门一中2018-2019学年高二上学期期末生物试题

甘肃省酒泉市玉门一中2018-2019学年高二上学期期末生物试题，扫描并关注下面的二维码，获取相关答案！

IALWAYSEXPERIENCEDthebeginningofanewschoolyearasawatershed.Movingupfromtenthtoeleventhgradewasamajorone.Myclasswasdisbandedamongthethreeotherparallelclasses.Quiteafewstudentshadfailedtomakethegrade，sofoursmallclasseswerecombinedintothreelargerones.Myhighschooltraditionallyhadtakenonlyboys.Whengirlsbegantobeaccepted，thereweresofewofthemtobeginwiththattheywerenotdividedequallyamongtheparallelclasses，butwereassignedtoasingleclass，thenlatertoasecondandathird，untiltheymadeupathirdofeachclass.Therewerenotenoughgirlsinmyyearforanytobeassignedtomyformerclass.Wewerethefourthparallelclass，andallboys，whichiswhyweweretheonestobedisbandedandreassigned，andnotoneoftheotherclasses.Wedidn’tfindoutaboutituntilschoolbegan.Theprincipalsummonedusintoaclassroomandinformedusaboutthewhyandhowofourreassignment.Alongwithsixothers，Icrossedtheemptyhallstothenewclassroom.Wegottheseatsthatwereleftover；minewasinthesecondrow.Theywereindividualseats，butinpairs，dividedintothreerows.Iwasinth找题眼法就是从多个已知条件中找出某一作为解题切入点的条件，从而得出答案的方法。其中最先使用的条件就是题眼。emiddlerow.OnmyleftIhadaclassmatefrommyoldclass，RudolfBargen，aheavyset，calm，dependablechessandhockeyplayerwithwhomIhadn’teverspentanytimeinmyoldclass，butwhosoonbecameagoodfriend.Onmyright，acrosstheaisle，werethegirls.MyneighborwasSophie.Brownhair，browneyes，brownsummerskin，withtinygoldenhairsonherbarearms.AfterI’dsatdownandlookedaround，shesmiledatme.Ismiledback.Ifeltgood，Iwasexcited 一、曲线运动1、曲线运动的条件：质点所受合外力的方向（或加速度方向）跟它的速度方向不在同一直线上。（1）当物体受到的合力为恒力（大小恒定、方向不变）时，物体作匀变速曲线运动 ，如平抛运动（只受重力）。（2）当物体受到的合力大小恒定而方向总跟速度的方向垂直，则物体将做匀速率圆周运动。（这里的合力可以是弹力——绳拴着的物体在光滑水平面上绕绳的一端旋转、重力与弹力的合力——锥摆、静摩擦力——水平转盘上的物体等。） （3）如果物体受到约束，只能沿圆形轨道运动，而速率不断变化——如小球被绳或杆约束着在竖直平面内运动，是变速率圆周运动。合力的方向并不总跟速度方向垂直。2、曲线运动的特点：曲线运"aboutanewstartinanewcla④是政府贯彻落实科学发展观、践行三个代表的需要。ss，andthegirls.Ihadobservedmymatesintenthgrade：whethertheyhadgirlsintheirclassornot，theywereafraidofthem，orkeptoutoftheirway，orshowedofftothem，o"