B. The levels of classification increased. Previously there were only 2 domains of life, Bacteria and Eukarya, but an additional domain and Kingdom were added when the distinction of Archaea was observed.
Hairpin like structures are formed in both DNA and RNA but are common in RNA than in DNA. This is because DNA can be double stranded or single stranded while RNA is generally single stranded structure that can be double stranded only when it forms a hair pin like structure.
The features of hairpin structure in RNA are as follows:
1. This structure is a building block of many secondary structures of RNA.
2. The termination sequence during transcription also forms a hairpin loop like structure.
3. tRNA also forms a hairpin loop like structure and helps in the process of translation.
For a introduced species to be invasive species, there needs to be certain characteristics of the species.
<h3><u>Explanation</u>:</h3>
Invasive species are the species that belong to some other place and are introduced to a new place by means of any human interference. But many species are often transferred from one place to another. But not all of them remain there as an invasive species. This is because for being an invasive species, they need to have certain characteristics:
A. They need to have high rate of reproduction.
B. They need to have short dormancy periods.
C. They need to have high generic variability.
D. They need to be polyphagous and gregarious.
E. They need to have high dispersal rate and great adaptability.
F. They need to have phenotypic plasticity.
1.) food
2.) water
3.) a habitat