Fish breathe through the ____, while other vertebrates usually breathe through the ____. Their bodies are covered with ____ and their swimming limbs are called ____. ____ fish have a swim bladder. Fish eggs do not have ____. However, in the rest of the ____ vertebrates, in order to avoid ____, there are eggs with shells. Mammalian mouths have lips for ____ milk. Breasts have ____, except in monotremes. In monotremes the young have to ____ the milk. In marsupials there is no placenta, so the young must remain inside the marsupial ____ after leaving the ____.

Vertebrates.

印刷
埋め込み

リーダーボード

表示スタイル

オプション

テンプレートを切り替える

自動保存: を復元しますか?