如图所示,请画出光线通过透镜后的光路图.
— Cheer up! If God closes a door in front of you, there ______ be a window opened for you.
下列属于人体内环境的组成成分是( )
①血浆、组织液和淋巴 ②血红蛋白、O2和葡萄糖
③葡萄糖、CO2和胰岛素 ④激素、递质小泡和氨基酸.