This image for day 193 of #LMB365 is provided by Jonathan Ribeiro in Gerry Crossan’s lab in the PNAC division. The Crossan lab studies how germ cells faithfully transmit genetic information from parent to offspring. Before becoming spermatozoa (sperm) or oocytes (eggs), germ cells undergo a sequence of cellular events including meiosis. During meiosis, germ cells switch from having two copies of the genome to having only one copy. This division of the genome is essential for the later fusion of a spermatozoon and an oocyte, or fertilisation, in order to produce a new individual with a normal chromosome count. This image is a snapshot of meiosis when chromosomes are preparing to segregate. Chromosomes are labelled in green and blue and sex chromosomes (that determine if the new individual is male or female) have a supplementary stain, in red.