Sunrise is not a prayer but u should be curious why they have sunrise in the prayer timetable.
1.Its forbiddden to pray Fajr after Sunrise.
2.Yes, its not a prayer but at Sunrise (Shurooq) there is an optional Prayer Called Duha Prayer.

If a Muslim performs the Fajr Prayer and then keeps offering dhikr or reciting the Qur'an until sunrise and then offer two rak`ahs of Duha, Allah Almighty will bestow on him great rewards.

To Know more about Duha Prayer, download a file from this link.
http://www.troid.org/ibaadah/as-salaah/reviving-a-sunnah-the-duha-prayer...

I would like to suggest u that u ask Islamic related Questions to Islamic Websites as they have educated scholars to answer ur Queries.

Ramadan on its Way.......:)