MICHEL DELARUE, ISM / SCIENCE PHOTO LIBRARY MICHEL DELARUE, ISM / SCIENCE PHOTO LIBRARY
Fertilised egg (zygote) of Xenopus laevis, the African clawed frog, which is widely used as a model organism in research in developmental biology. It is popular in this field as its egg cells are large and easily manipulated in the laboratory. The dark region of this zygote marks the area where the sperm cell entered the egg. The egg cell is around one millimetres in diameter, which means that the magnification of this image is x57 when printed 10cm wide.
Model release not required. Property release not required.