Light micrograph of the encounter between sperm and ovum during in vivo fertilisation (IVF). A single sperm is seen in centre of image approaching the

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Light micrograph of the encounter between sperm and ovum during in vivo fertilisation (IVF). A single sperm is seen in centre of image approaching the circular oocyte. Other competing sperm and cells comprising the corona radiata, which forms a protective halo around the central oocyte, are visible at bottom. Only one sperm will be successful in penetrating the oocyte; at the instance this occurs the oocyte membrane thickens to construct a barrier to competing sperm. In IVF, egg and sperm meet in a petri dish and subsequent events are monitored through a microscope to check for successful fertilisation.

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Size: 4852px × 3594px
Photo credit: © EDELMANN/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomy, body, corona, fertilisation, fertilization, human, light, micrograph, oocyte, radiata, reproduction