Answer: crossing over, process in genetics by which the two chromosomes of a homologous pair exchange equal segments with each other. Crossing over occurs in the first division of meiosis . At that stage each chromosome has replicated into two strands called sister chromatids.
"Benzaldehyde is an organic compound consisting of a benzene ring with a formyl substituent. It is the simplest aromatic aldehyde and one of the most industrially useful. It is a colorless liquid with a characteristic almond-like odor."
https://www.britannica.com/science/benzaldehyde
https://en.wikipedia.org/wiki/Benzaldehyde
It is the serous membrane
It is also possible to move substances across membranes against their concentration gradient (from areas of low concentration to areas of high concentration). ... If the energy of ATP is directly used to pump molecules against their concentration gradient, the transport is called primary active transport.
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