题目

下列关于动物体内酶和激素的叙述，正确的是（）①激素和酶的功能都具有专一性      ②它们都是蛋白质③都是由内分泌细胞分泌的          ④有的动物细胞既能产生激素又能合成酶⑤能产生酶的细胞不一定能产生激素   ⑥能产生激素的细胞不一定能产生酶⑦激素产生后一般作用于其他细胞．      A．①②⑤              B．④⑤⑥⑦               C．①④⑤⑦       D．①②③⑤⑥My Dog MandyThis is Mandy. She is the best dog! I got her a few months ago when she was just a little puppy（baby dog）. She has grown a lot since then! She is a small，brown and white dog with a cute nose and ears.Over the past few months we have become good friends. We have spent lots of time together having fun. We go to the park almost every day. We have friends that we meet at the park, so Mandy has other dogs to play with. They run and bark（犬吠） together. Mandy is a small dog but she barks quite loudly. Mandy has learned how to catch a ball. Her favorite toy is a small blue and yellow ball that she can catch in her mouth very easily. She has short legs but she can jump high! It is a game that she likes to play，so we have played it a lot! She is happy and wags （摇）her tail when she catches the ball.She has been good company. Mandy has learned how to jump up on my lap（大腿） when we are at home. Mandy and I have become very close friends and I love her a lot.【1】What does Mandy look like?A. She has a small nose.B. She has big ears.C. She is large，black and white.D. She is small，brown and white.【2】The writer often takes Mandy to the park because ___________.A. Mandy likes to barkB. Mandy likes jumpingC. Mandy wants to have funD. The park is beautiful【3】What can we learn about the writer and Mandy?A. They often run together.B. They work in the same company.C. They often watch games together.D. They are good friends.