False colour light micrograph of a mouse embryo, taken at the end of the first mitotic division of the unicellular zygote, the recently fertilised ovu

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False colour light micrograph of a mouse embryo, taken at the end of the first mitotic division of the unicellular zygote, the recently fertilised ovum. From now on the 2 almost fully- formed cells will divide into 4, then 4 into 8, and so on, to form a ball of cells known as the morula. As the number of cells, called blastomeres, increases the individual blastomeres become smaller, so that the overall size of the cellular aggregate does not increase at first. The well-defined exterior wall around the embryo is the zona pellucida, a protective glycoprotein layer. Magnification: X 31 at 35mm size. Original is bw print p681/018.

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Size: 2480px × 3806px
Photo credit: © DAVID SCHARF/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 2, anatomy, animal, body, cells, embryo, light, micrograph, mitosis, mouse, pellucida, zona