知识贝壳
知识贝壳
所属栏目：英汉双解生物学
1. The reflex process inthe eye by which an image is focused on theretina. In humans,the eye at rest is focusedon infinity,with the lens and cornea flat-tened,To focus on a near object the ciliarymuscles contract,and the lens,being elas-tic,becomes more c ......（本文共 894 字 ） [阅读本文] >>