What happens in Chapter 2 of the Hunger Games?

Katniss Everdeen goes hunting with her friend Gale and they talk about the "Reaping" to happen later that day. When she goes home she fixes dinner for her family and they go to the Reaping. Primrose Everdeen - Katniss's little sister - is chosen to enter The Hunger Games but so she won't get killed Katniss takes her place. The other person is chosen and it is Peeta Mellark, the boy who gave her bread after her father died (in a mine explosion many years earlier) and Katniss gets worried about killing him.