Final answer:
Transposable elements (TEs), or jumping genes, are DNA sequences that can move to different locations within a genome, introducing genetic diversity. They were first discovered by Barbara McClintock in the 1940s in maize. These elements can significantly affect gene function and play a vital role in species evolution.
Step-by-step explanation:
Understanding Transposable Elements (TEs)
Transposable elements (TEs), also known as jumping genes, are segments of DNA that can move around to different positions within the genome of a single cell. This process is called transposition. The exciting discovery of these elements was made by the American geneticist Barbara McClintock in the 1940s while she was examining patterns of colors on maize kernels, demonstrating that genes can be dynamic in their position within the genome.
Transposons contain special inverted repeat sequences at their ends and a gene for an enzyme called transposase, which facilitates their movement. They can employ a "cut-and-paste" method, where the transposon is excised from one position and integrated into a new location, or a "copy-and-paste" method, where a copy is made and inserted elsewhere without the original transposon being removed.
Through their ability to jump from one location to another, transposable elements introduce genetic diversity within the genome and can have a significant impact on gene function. They are capable of activating, deactivating or even creating entirely new genes. This mobility and activity enable these elements, which were once considered merely 'junk DNA', to play a crucial role in the evolution and adaptation of species.