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.
Shell Downstream is one of the worldâs largest businesses in the production and. distribution of petroleum and chemical products. In 2003, Shell embarked upon a radical change to its business model from a country centric approach to a global product line.basis.hell Downstream. Shell Downstream is one of the worldâs largest businesses in the production and. distribution of petroleum and chemical products. In 2003, Shell embarked upon a radical change to its business model from a country centric approach to a global product line. basis.