Biology - topic 1

Biological molecules

What is life based upon

All life is carbon based

Carbon forms the “back bone” of organic molecules

Organic molecules all have a similar biochemical basis. They all contain a carbon backbone covalently bonded with hydrogen and a few other elements

Organic molecules often contain oxygen, nitrogen and phosphorus

What are momomers

Monomers are the smaller units from which larger molecules are made

What are polymers?

Polymers are molecules made from a large number of monomers joined together

Examples of monomers

Nucleotides, monosaccharide and amino acid

Examples of polymers

polynucleotide (DNA), polysaccharide e.g starch, polypeptide (protein)

What is a condensation reaction

It joins two molecules together with the formation of a chemical bond and involves the elimination of a water molecule

What is a hydrolysis reaction

A hydrolysis reaction breaks a chemical bond between two molecules and involves the use of a water molecule

What are disaccharides and how are they formed

Two monosaccharides joined together with a glycosidic bond

Formed by a condensation reaction, releasing a water molecule

How is maltose formed (a disaccharide)

Condensation reaxtion between two alpha glucose molecules make glyosidic bonds involving an elimination of a water molecule where a H group from one glucose is lost and an OH group of the other glucose is lost to form H20.

How is a peptide bond formed

Condensation reactions between amino acids make peptide bonds