Final answer:
Transposons are DNA segments capable of moving within a genome, leading to genetic diversity. They come in various forms and can transfer genes such as those for antibiotic resistance. Transposons require the enzyme transposase to move and can be either autonomous or non-autonomous depending on their components.
Step-by-step explanation:
Transposons, also known as transposable elements or 'jumping genes,' are segments of DNA that can move to various positions within the genome of a cell. They have been discovered in organisms ranging from bacteria to humans and are responsible for creating genetic diversity. There are a few types of transposons, including Insertion Sequences (IS Elements), which were first identified in bacteria, and Composite Transposons (Tn elements) which can carry antibiotic resistance genes alongside other genetic material.
Transposons work by a mechanism called transposition, which can either be 'cut-and-paste', where the DNA segment moves entirely, or 'copy-and-paste', where a replicated copy is inserted elsewhere in the genome. They can cause mutations and alter gene function, thereby affecting the phenotype of an organism. In bacteria, the movement of transposons is clinically relevant due to their role in spreading antibiotic resistance among populations.
Transposons code for an enzyme called transposase that facilitates their movement. Not all transposons are active; some may be silenced by mutations or other factors. For instance, in maize, an autonomous transposon has all the machinery necessary for movement, while non-autonomous transposons require assistance from an autonomous element.