海星是低等的海洋无脊椎动物。五条腕的海星形状很像五角星,它的口位于腹面。肛门在背面。当海星用腕和管足把食物抓牢后,就把胃从嘴里翻出来,包住食物进行消化,然后再把胃缩回体内。若把海星撕成几块抛入海中,每一块都会很快重新长出失去的部分。科学家正在探索海星再生能力的奥秘,为人类寻求新的医疗方法。 Starfish are inferior marine invertebrates. The five-star wrist star is shaped like a star, its mouth is in the ventral surface. The anus is on the back. When the starfish grasps the food with its wrists and feet, it pulls the stomach out of its mouth, wraps it around, digests it, and then retracts it back into the body. If you tear a seastar into pieces and throw it into the sea, each piece will soon grow back to its lost part. Scientists are exploring the mysteries of the regenerative capacity of sea stars and seeking new medical methods for humans.