Name the following structures. (pts) HO OH NH3 NH2 HO-P-O-P-OH
The Correct Answer and Explanation is:
Here are the correct names for the structures shown in the image:
a. Citric acid
b. Glutamic acid (in its zwitterionic form)
c. Adenosine triphosphate (ATP)
Explanation:
a. Citric acid:
This molecule has three carboxylic acid groups (–COOH) and one hydroxyl group (–OH) attached to a central carbon chain. It is a tricarboxylic acid commonly found in the citric acid cycle (Krebs cycle), crucial for energy production in aerobic organisms. Its structure consists of a six-carbon backbone with three carboxylic acid groups, making it a triprotic acid.
b. Glutamic acid (zwitterion):
This is an amino acid structure. It features two carboxyl groups (–COO⁻ at physiological pH) and one amine group (–NH₃⁺). The side chain is a –CH₂CH₂COO⁻ group, characteristic of glutamic acid. The structure shown here is a zwitterion: a molecule with both positive and negative charges but overall neutral. This form is typical at physiological pH (~7.4). The central carbon is chiral, with an L-configuration in biological systems.
c. Adenosine triphosphate (ATP):
This molecule is the primary energy currency of the cell. It consists of:
- An adenine base (a purine),
- A ribose sugar (a five-membered ring with hydroxyl groups),
- Three phosphate groups connected in sequence.
ATP stores energy in the high-energy phosphate bonds, particularly between the second and third phosphate groups. When hydrolyzed (ATP → ADP + Pi), energy is released for cellular processes like muscle contraction, active transport, and biosynthesis.
Understanding the structures of these molecules is essential in biochemistry. Citric acid is part of the Krebs cycle; glutamic acid is a key neurotransmitter and precursor to GABA; ATP drives nearly all biochemical reactions requiring energy.
