In recombinant dna experiments, what is used to cut pieces of dna and what joins the resulting fragments to form recombinant dna

DNA fragments are cut out restriction enzymes (restriction endonucleases) and then joined together using enzymes called DNA ligases.

Restriction enzymes are enzymes which recognize target sequences (recognition sites) and cuts DNA at or near those sequences.

DNA ligase is an enzyme that connects the gap between the molecules (if they have matching ends).

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

: -)

the diploid number of chromosomes is sometimes represented by the symbol 2n. for the fruit fly, the diploid number is 8, which can be written as 2n = 8, where n represents twice the number of chromosomes in a sperm or egg cell.