Questions

The correct pairing of DNA bases among the given options is guanine - cytosine.

When both sides have won the same number of points then: when each side has won one, or two, points, the score is described as "15-all" and "30-all" (or "15-up" and "30-up"), respectively.

However, if each player has won three points, the score is called as "deuce", not "40–all". From that point on in the game, whenever the score is tied, it is described as "deuce", regardless of how many points have been played.

Tetley

Amino acids are organic compounds containing amine (-NH2) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid.

Depending on the nature of the side chain groups, three classes of aminoacids can e distinguished:

1. Amino acids with H ond donor and acceptor groups.

Histidine, lysine, aspartic acid, threonine,...

2. Amino acids with donor grups only.

Arginine, tryptophan and cysteine.

3. Amino acids with acceptor groups only.

Asparagine and glutamine.