Answer:
C. They all use a cut and paste mechanism.
Explanation:
DNA transposons can go through a replicative or nonreplicative transposition.
The replicative transposition uses a "copy and paste" mechanism that consists of the introduction of a new copy of the transposable element in a new position, meanwhile <u>the old copy remains in the original position</u>. This determines an increase in the number of copies.
The nonreplicative transposition uses a "cut and paste" mechanism that consists of the cleavage of the transposable element from its position and its <u>insertion in a new position</u> without increasing the number of copies.
Retrotransposons, on the other side, move through RNA intermediates generated by the reverse transcriptase.
Answer:
A. the cell membrane protects the cell
Ok here we go:
Science starts with observing which leads to hypothesis, which is tested by experiments.
The other two i am not sure of. Hope i was a help to you. One thing you can do to figure out the other two is google: "what type of science includes medicine and envirnmental science", and do the same for the other one.