The extra costs forprenatal care and complicated births among women whosmoke during pregnancy are more than $4 billion ayear. 1 Care for childhood illnesses resulting fromexposure to tobacco smoke costs nearly $8 billion a year.As a result, reducing parental smoking can producesubstantial economic benefits for society.
If the amine and carboxylic acid functional groups in amino acids join together to form amide bonds, a chain of amino acid units, called a peptide, is formed. A simple tetrapeptide structure is shown in the following diagram.
The shapes of some amino acid molecules Peptide bond formation Two amino acids can undergo a condensation reaction to form a dipeptide. Further condensation reactions result in a polypeptide. The amino acid units are linked by peptide bonds (sometimes called peptide links).