识图回答问题:写出名称:①____ ⑤____ ⑥____ ⑧____ ⑨____ (2)鸟类的卵黄表面中央有个小白点,称为____ 里面含有____ 。(3)鸟的胚胎发育所需是营养是____ 、____ 提供。
____ with a new type of machine, the explorers went into a cave, hoping to find some buried treasure.