Biological Molecules Condensed Notes

Biological Molecules
Contents
● Carbohydrates
○ Monosaccharides and Disaccharides
○ Polysaccharides (cellulose, glycogen starch)
● Lipids
● Proteins
○ Structure
○ Enzymes
○ Amino acids
● Nucleic acids
○ Nucleotides (ATP, RNA, DNA)
○ Semi conservative replication
● Water
● Inorganic ions


● All life shows the same basic biochemistry including carbon, hydrogen, oxygen and
nitrogen
● Many organic molecules are made up of a chain of individual molecules
○ Monomers join together to form polymers
■ E.g monosaccharides join to make polysaccharides

● Carbohydrates
○ Test for reducing sugar: Heat with Benedict’s reagent and if it turns yellow, green,
orange or brick red there is a reducing sugar.
■ Non reducing sugar: After completing reducing sugar, heat the new
sample with dilute HCl and neutralise with NaHCO3. Add Benedicts again

○ Alpha glucose structure




○ Beta glucose structure

, ● Condensation reaction and hydrolysis




● Disaccharides
○ Maltose → alpha glucose + alpha glucose
○ Sucrose → glucose + fructose
○ Lactose → glucose + galactose

● Polysaccharides
○ Glycogen
○ Starch
■ Amylose - unbranched and coiled for storage (compact)
■ Amylopectin - branched so glucose can be released quickly
○ Cellulose

● Test for starch: Iodine turns Blue/Black in the presence of starch

● Lipids
○ Types
■ Triglyceride