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.
Drilling and Operating Wells for Crude Oil. The final big stage in the upstream segment of the oil industry is the drilling and operating of wells that are producing crude oil. One of the main criteria that separates the upstream category from the midstream category is the nature of the oil it produces.