It is one of the defining characteristics of living things Like many other organisms, human beings reproduce sexually Sexual reproduction involves two parents As you can see from figure 5.12.2, in sexual reproduction, parents produce reproductive (sex) cells — called gametes — that unite to form an offspring Sexual reproduction was an early evolutionary innovation after the appearance of eukaryotic cells The fact that most eukaryotes reproduce sexually is evidence of its evolutionary success
In many animals, it is the only mode of reproduction And yet, scientists recognize some real disadvantages to sexual reproduction On the surface, offspring that are genetically identical to the parent may. This ensures the offspring are genetically different from their parents and even their siblings Mutations can also happen in sexually reproducing species to further add to the diversity of the offspring Explain how sexual reproduction occurs at the cellular level
Compare and contrast gametogenesis in males and females Explain mechanisms that increase genetic variation in offspring produced by sexual reproduction Why do gametes need to be haploid? Sexual reproduction occurs when the sperm from the male parent fertilizes an egg from the female parent, producing an offspring that is genetically different from both parents. By the end of this section, you will be able to do the following 11.1.4 describe how sex differences can extend to physiological and behavioral traits beyond reproduction have you ever wondered why most species around you reproduce sexually, and why having two distinct sexes is so common
What are the benefits of sexual reproduction, and why are the two sexes in many species so different from each other?
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