The Census of Marine Life has been the biggest and most comprehensive attempt ever to answer that question-how many fish are there in the world's oceans? The Census of Marine Life, which hopes to indicate a baseline of marine fife, estimates that there are more than 230,000 Q31 species ...
There are more than 40 types of dolphins, yet the number continues changing as science studies these warm-bloodedmarine animals. Most dolphins are important for the Delphinidae family, which remembers those living for the sea, yet some different species live in streams and have an alternate ordere...
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There are few sights as impressive as the mass migrations of animals. To the animals themselves, these migrations are crucial to the survival of their species. Here, we'll figure out the reason animals make such astonishing journeys. Migration is the large-scale movement during an animal species...
Is it possible that there are whales well below the surface that are more than a hundred years old? One thing we do know is that whales are mammals and therefore breathe air to live. So even if there are whales that are deep divers, they have to come to the surface at some point so...
How would youcount how many whales there are in the ocean?体裁:说明文Capturing live whales and bringing them out of the题材:无人机应用ocean without harming them is awkward. After all they词数:337are the biggest creatures that currently live on our planet.难度As for counting the population, ...
How many oceans are there?到底有多少个大洋？A new ocean has appeared on the maps of the National Geographic Society. The Southern Ocean, which encircles Antarctica, will henceforth be given the same status, and typeface, as the Arctic, Atlantic, Indian and Pacific Oceans. But of ...
Think of how complex the brain is and how many tasks it performs: It keeps you breathing, it reminds your heart to beat, it records all the memories of your life, and it enables you to laugh, cry, love and converse. Now think of how you sleep, how your body moves from dreams to ...
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男性，35岁，反复大便出血2年，色鲜红，无明显疼痛，既往大便常干结。直肠指检未触及肿块，肛门镜检查见齿状线上2处黏膜隆起。最可能的诊断是A、内痔B、外痔C、直肠息肉D、肛乳头肥大E、直肠癌该患者的临床分度属A、Ⅰ度B、Ⅱ度C、Ⅲ度D、Ⅳ度E、Ⅴ度 ...