题目

有关激素调节特点的叙述中，错误的是 （ ）A.激素一经靶细胞接受并起作用后就被灭活了B.内分泌腺产生的激素通过导管输送到体液中，随血液流到全身C.体内需要源源不断的产生激素，以维持激素含量的动态平衡D.激素既不组成细胞的结构，又不提供能量，也不起催化作用 答案：【答案】B【解析】AC、激素一经靶细胞接受并起作用后就被灭活了，保证内分泌腺源源不断产生新激素，维持激素含量稳态，AC正确；B、内分泌腺产生的激素通过血管输送到血液，随血液流到全身，B错误；D、激素作用于靶细胞，调节靶细胞代谢，不组成细胞的结构，又不提供能量，也不起催化作用，DWork is a part of living—my grandparents understood that.They lived and worked on a farm that has been in my family for 150 years.They raised chickens for eggs,pigs and cattle for meat.Cows were kept for milk and the cream,from which Grandma made butter and cheese.What little yard they had became a garden.The Depression（大萧条时期）,therefore,didn’t make much change in their lives.But it did bring a lot of men out of work,drifting from job to job,to the farm.The first to show up at the door of the kitchen was a man in rags.He took off his hat and quietly explained that he hadn’t eaten for a while.Grandpa stood watching him a bit,then said, “There’s a stack of firewood against the fence behind the barn（谷仓）.I’ve been needing to get it moved to the other side of the fence.You have just about enough time to finish the job before lunch.”Grandma said a surprising thing happened.The man got a shine in his eyes and he hurried to the barn at once. She set another place at the table and made an apple pie.During lunch,the stranger didn’t say much,but when he left, his shoulders had straightened.“Nothing ruins a man like losing his self-respect,”Grandpa later told me.Soon after,another man showed up asking for a meal.This one was dressed in a suit and carried a small old suitcase.Grandpa came out when he heard voices.He looked at the man and then offered a handshake.“There is a stack of firewood along the fence down behind the barn I’ve been meaning to get it moved.It’d sure be a help to me. And we’d be pleased to have you stay for lunch.”The fellow set his suitcase aside and neatly laid his coat on top. Then he set off to work.Grandma says she doesn’t remember how many strangers they shared a meal with during those Depression days-or how many times that stack of wood got moved.【1】When he was asked to move a stack of firewood,the first man who asked for a meal got a shine in his eyes for he was glad that .A. he had found a good jobB. he would have something to eatC. he would no longer suffer from the DepressionD. he would get what he wanted without losing his self-respect【2】The writer’s grandfather asked those jobless men to move the stack of firewood because .A. he didn’t want them to have a meal free of chargeB. he had been needing to get it movedC. he wanted to help them in his own wayD. he wanted to show them his kindness and respect【3】The writer’s grandfather was all of the following but .A. kind B. thoughtfulC. wealthy D. sympathetic【4】The best title for the story would be .A. The Depression B. The Pleasure of Helping OthersC. No Pains,No Gains D. Work-A Part of Living