An ovum (plural ova, from the Latin word ovum meaning egg or egg cell) is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization. In lower plants and algae, the ovum is also often called oosphere.

In higher animals, ova are produced by female gonads (sexual glands) called ovaries and all of them are present at birth in mammals and mature via oogenesis.

In the viviparous animals (which include humans and all other placental mammals), the ovum is fertilized inside the female body and the embryo then develops inside the uterus, receiving nutrition directly from the mother.

The human ova grow from primitive germ cells that are embedded in the substance of the ovaries. Each of them divides repeatedly to give rise to several smaller cells, the oogonia. The oogonia then develop via meiosis into the ova, the primary oocytes, and the polar bodies.

Harry Romero, better known as Harry "Choo Choo" Romero, is an American DJ and record producer. He is linked with the label Subliminal with Erick Morillo and Jose Nunez, with whom he also produced and remixed several tracks, as 'Constipated Monkeys', 'The Dronez' or 'Ministers De La Funk'. The trio won the Muzik Magazine Remixer of the Year award in 1999. When working alone, he also uses the pseudonyms 'HCCR' and 'Mongobonix'. Romero owns a sub label of Subliminal called Bambossa, in which he has released six tracks, including "Tania", "What Happened", "Son of Mongo" and "Warped".

Romero has mixed several of the Subliminal Sessions series of mix albums, blending releases from the Subliminal stable with other current house tracks. His latest release was a remix of a Nick & Danny Chatelain track called "Me Resuelve". He continues to play at Subliminal session parties worldwide, including those in Pacha, Ibiza. In 2007, he set up a four date residency throughout the year at the SE1 club in London, with the last party taking place on 10 October that year.