Organic acids
The carboxyl end of a molecule would typically be found at the "end" containing a carboxyl group, which consists of a carbon atom double-bonded to one oxygen atom and single-bonded to a hydroxyl group (-OH). In amino acids, for example, the carboxyl end is designated as the terminus with the carboxyl group.
amino acid
Yes, fatty acids have a carboxyl group at one end, which is a functional group consisting of a carbon double-bonded to an oxygen and also bonded to a hydroxyl group. This carboxyl group is what gives fatty acids their acidic properties.
Carboxyl Group
Both amino acids and fatty acids contain a carboxyl group at one end of the molecule. This carboxyl group consists of a carbon atom double-bonded to an oxygen atom and single-bonded to a hydroxyl group (OH).
A simple fat molecule is composed of one glycerol molecule, which is a simple sugar, and three fatty acid chains, which are chains of carbon and hydrogen with a carboxyl group at one end.
Generally, a fatty acid consists of a straight chain of an even number of carbon atoms, with hydrogen atoms along the length of the chain and at one end of the chain and a carboxyl group (―COOH) at the other end. It is that carboxyl group that makes it an acid (carboxylic acid).
Proteins are composed of amino acids, which are composed of a central Carbon atom surrounded by (bonded to) four groups; an amine, a carboxyl group, an R group (also known as a side chain), and a Hydrogen atom. When amino acids link together via peptide bonding to from polypeptides/proteins (A protein is a polypeptide), the amine group of one amino acid interacts with the carboxyl group of another. Therefore, you end up with an amine group on one end of the protein and a carboxyl group on the other. They call the end with the amine on it the "N terminus" because the chemical formula for amine is NH2 while the end with the carboxyl group on it is named the "C terminal" because the chemical formula of a carboxyl is CH2. The N terminus is the end that amino acids are added onto when mRNA is translated in protein synthesis. Therefore, we write that proteins are created N terminus to C terminus.
The carboxyl group is polar.
They all have a hydrocarbon chain with a carboxyl group on the end.
The fatty acids have carboxylic group 'COOH' at terminal this is a group having 'OH' group attached to carbonyl carbon but it is not alcohol.
This kind of molecule is called a fatty acid. Fatty acids are comprised of a hydrocarbon chain with a carboxyl group at one end, which makes them amphiphilic molecules important for cellular structure and energy storage.