DNA transposons, viral-like transposable elements, and non-LTR retrotransposons
Explanation:
Transposable Elements (TEs) are genetic mobile elements that can change its position within a genome, thereby producing mutations at the genomic sites where they are inserted. According to their composition and structure, TEs can be divided into three main types: DNA transposons, viral-like transposable elements, and non-long terminal repeat (non-LTR) retrotransposons (also known as polyA retrotransposons). In the first place, DNA transposons are composed of conserved inverted repeat sequences at both ends of the element which are surrounded by target site duplications (TSDs). Moreover, viral-like TEs contain LTRs and they encode reverse transcriptase enzymes. Finally, non-LTR retrotransposons contain a poly(A) tail at the 3′ end, but they don't have inverted repeats.
Backup of sewage in the preparation area or a serious pest infestation are hazards or contaminants that are grounds for immediate closure of an operation. A sewer drain backup may be among the most unpleasant experiences one can get as a house owner.
Explanation: You're supposed to have numerically more smaller units than bigger units, since a lot of these smaller units are combined to create a single larger unit.