Sperm fertilising an egg (IMAGE) Walter and Eliza Hall Institute Caption A sperm cell fertilising an egg cell. The sperm carries genes from the father to the offspring, but our research has shown it could also carry a legacy of a father's infection with the Toxoplasma parasite. Credit Walter and Eliza Hall Institute, Australia Usage Restrictions With credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.