Theoretically, in vitro fertilisation could be performed by collecting the contents from a woman's fallopian tubes or uterus after natural ovulation, mixing it with sperm, and reinserting the fertilised ova into the uterus.
Upstream operations deal primarily with the exploration stages of the oil and gas industry, with upstream firms taking the first steps to first locate, test and drill for oil and gas. Later, once reserves are proven, upstream firms will extract any oil and gas from the reserve.
A: Sun, source of solar energy. It transfers thermal (heat) and light energy to plants, humans and animals. B: River, streams and waterfalls moving downstream are all a source or water energy (HydroPower). They are a store of kinetic energy by their movement downstream.