In vitro fertilisation (IVF): ovum post ovulation. False-colour scanning electron micrograph (SEM) of a single human ovum (egg), showing its protectiv

---

In vitro fertilisation (IVF): ovum post ovulation. False-colour scanning electron micrograph (SEM) of a single human ovum (egg), showing its protective covering, the zona pellucida (red) & remnants of the layer of follicular cells that form the corona radiata. Mature ova develop from primordial follicles formed during foetal development that remain dormant until sexual maturity. Every month, up to 20 follicles are activated to form primary follicles; normally only one attains full maturity to be released when the follicle ruptures at ovulation. Magnification: x470 at 6x7cm size.

---

Size: 3834px × 3347px
Photo credit: © MOTTA & FAMILIARI/ANATOMY DEPT./UNIVERSITY LA SAPIENZA", ROME/SCIENCE PHOTO LIBRARY" / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: anatomy, body, cells, egg, false-coloured, female, fertilisation, fertility, follicular, human, image, images, ivf, magnified, microscopic, ovum, pellucida, photos, reproduction, reproductive, subjects, system, vitro, zona