Someseaurchins海胆havevenomous(toxin)spines

Thefirstpaperwasmadefromthebarkofthemulberrytree.

One of the greatest breakthroughs for professional women came in 1973 when the field of banking opened up for them.

Food must be moist in order to have a taste.

Eyespots, the most rudimentary eyes, are found in protozoan原生动物 flagellates 鞭毛虫 , flatworms 扁形虫 , and segmented worms片段 蠕虫 .