It seems likely that, in this context, the relevant meaning of translocation is the movement of sucrose and other organic substances from their sources in mature leaves to the many sinks, or places where they are needed, throughout the plant. Sinks may include roots, fruits, and immature leaves, so that leaves are sinks at one stage of their development and sources at another.
Translocation of nutrients occurs in the phloem, a specialized tissue that, together with the xylem, which transports water and minerals absorbed through the roots, make up vascular bundles. Translocation occurs much more rapidly than diffusion. Active transport of sugars into the sieve elements of the phloem concentrates the sugars, causing a build up of osmotic pressure. Because the sugars are removed at the sink locations, the concentration, and hence the osmotic pressure, is much less. Nutrients flow along the pressure gradient thus created at speeds of up to a meter per hour.
Despite both of these words having a spelling that is somewhat similar, the processes that each term refers to are vastly different.
Transpiration is the process by which water in plant leaves vaporizes and returns to the atmosphere. The water travels from the roots to the leaves, and the solar energy then causes the liquid water to change into water vapor. Transpiration is essentially evaporation out of plants.
Translocation is a genetic change to a chromosome. It occurs when a segment of a chromosome breaks off and attaches to a different chromosome. It can also occur when two segments from different chromosomes trade places with each other. Conceptually, it is similar to a process called crossing over, which occurs during meiosis; however, crossing over occurs between homologous pairs, and translocation happens to non-homologous chromosomes.
https://biologywise.com/what-is-crossing-over-why-is-it-important-in-meiosis
https://www.usgs.gov/special-topic/water-science-school/science/evapotranspiration-and-water-cycle
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