单词：primary spermatogenous cell
单词：primary spermatogenous cell 相关文章
Why are there males and females? Why are there two sexes instead of three, or twelve, or one? On this Moment of Science we'll learn why two is the magic number. Let's start with why there is sex at all. When two organisms reproduce sexually, sperm an
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Egg Cells 卵细胞 Do you know what an egg cell is? 你知道什么是卵细胞吗？ An egg cell is necessary for reproduction. 卵细胞是繁殖的必要条件。 Animals have egg cells. 动物有卵细胞。 Then does every animal have egg cells
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WASHINGTON, Aug. 4 (Xinhua) -- Researchers have found a way to turn mouse embryonic stem cells into sperm and this finding opens up new avenues for infertility research and treatment, according to astudy published Thursday in the online edition of jo
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Our bodies are amazing. Although things go wrong at times, it's remarkable they work at all when one considers the complexities of their operation. Don and Ya?l present some awards to a few of the outstanding components. [APPLAUSE] D: Good evening, Y
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In mammals, the sex of a baby is determined by the combination of chromosomes it inherits from its parents. Nearly every cell in a male body has two different sex chromosomesone is shaped like an X and one is shaped like a Y. Females also have two se
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