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.
What is 'Upstream'. Oil and gas companies can generally be divided into three segments: upstream, midstream and downstream. Upstream firms deal primarily with the exploration and initial production stages of the oil and gas industry. Many large oil companies are called integrated because they combine upstream activities with midstream and downstream operations, which take place after the production phase through to the point of sale.