Sea horses are unusual parents. The female sea horses lay the eggs，but unlike other creatures，it’s t...
Male sea horse have a fold of skin on their bellies that forms a pocket，called a brood pouch. During the breeding season，the sea horse’s pouch swells to receive eggs. A female sea horse lays up to 200 eggs at a time in the pouch. Then she swims off，leaving her male partner to care for the developing eggs and give birth to young sea horses. The female will return every day to check on her mate and the eggs，but she doesn’t stay long，nor does she take part in the birth.
It takes from two to six weeks for the eggs in the male’s pouch to develop. During this time the male avoids open water and hides in sea grass. His big pouch makes it difficult for him to swim，so the male often uses his tail to grasp a piece of sea grass. Firmly，gripping the grass，he will stay perfectly still for hours or even days. The male sea horse will change his color to blend with his surroundings and avoid being seen by predators who will try to eat him or poke holes in his pouch to get the eggs.
The eggs hatch inside the male’s pouch. When the babies begin moving around，the male sea horse knows it’s time for them to be born. He grabs a sea grass stem with his tail and begins rocking，bending，and stretching his body back and forth． This causes the opening to enlarge until it is wide enough for the first baby sea horse to shoot out. The father sea horse continues rocking，bending，and stretching his body so that the rest of the babies can be born. Sometimes he has to press his pouch against a rock or some stiff seaweed to force the young out.
Sea horse babies are born in groups of five or more. Sometimes it takes two days for the father sea horse to give birth to all his young. He is very tired when it’s over.
Soon after giving birth to one brood，the male will approach his mate and show her his empty pouch. This tells her he is ready to receive eggs again.
36. What part does the female sea horse play in having babies？
参考答案: B
参考解析: 海马是不寻常的父母，雌性海马产蛋，但不同于其他生物，雄海马负责繁殖后代。
雄海马的腹部有一块褶皱的皮肤从而形成口袋状，我们可以称之为育儿袋。在繁殖期， 海马的育儿袋会膨胀接受卵子。雌海马一次可在袋子中产下大约200个蛋。然后她会游走，留给雄海马培育和孵化卵子。 雌海马每天会回到雄海马的身边检查她的伴侣和它的孩子，但仅仅停留一会，并不会参与孵化。
大概需要两到六周雄海马育儿袋中卵子才会发育成形。在此期间，雄海马应防止地表水并隐藏在海草中。它的庞大育儿袋让它难以游动， 所以雄海马通常会用它的尾巴抓住一条海草。紧紧地抓着，一动不动地呆上几小时甚至几天。雄性海马要改变自身颜色以便与四周环境颜色混同从而防止被捕食者发现，因为这些捕食者试图吃掉它或刺穿他的袋子得到卵子。
小海马会在雄性海马的袋子中孵化成长。当小海马在袋子中不断移动的时候，雄性海马就知道它快要出生了。此时雄性海马用自己的尾巴紧紧缠住海草的茎，并开始前后翻滚。这样可使第一个小海马顺利地从袋中挤出来。雄海马不断地滚动，弯曲身体，把它的小海马从袋中挤出来。雄海马继续地滚动，弯曲，这样剩余的小海马才得以出来。有时它还得把袋子紧靠在石头上或很硬的海草上，用力挤压育儿袋把即将出生的小海马挤出来。
小海马一般是一窝生四五个或更多。有时要花上一两天的时间才能顺利生产这些小海马。生育结束后，雄海马很劳累。
这样在生下一窝小海马之后，雄性海马将靠近它的伴侣并向它展示它的空育儿袋。这个动作是在告知雌海马，它准备接受新卵子。
【考点类型】细节判断
【解析过程】雌性海马在产子的时候扮演什么角色？
A. 受卵 B. 产卵 C. 孵化 D. 保护卵子
线索：文章第2段提到“A female sea horse lays up to 200 eggs at a time in the pouch. Then she swims off，”所以答案选B。选项A、C、D都是说雄性海马的责任。
【考点提示】科普类型的文章一般都是同学们以前没有读过的文章，也就是说文章在选材上一定是具有新颖性的，所以文章的内容往往是和我们的以往认识有一定的不同，这篇文章就是如此，雄性海马负责孵化和保护小海马。
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