Welcome to class of

Principles of Biochemistry

Dr. Meera Kaur

What is Biochemistry?

• A scientific discipline• Explains life at the molecular level• Explains biological forms and

functions in chemical terms• Forms basis for studying other fields like cell biology, genetics, medicine, nutrition, immunology etc.• Closely relates to other discipline like chemistry, physics, mathematics

Levels of organization in a living organism.

What is biomolecule?

• What are living organism made of ?

• How are they made ?

Biomolecules

• Living matters are made out of biomolecules• Biomolecules are made of lighter elements • They are mostly combined with covalent bonding • Biomolecules are compounds of carbon• Biomolecules have functional groups• Most biomolecules are asymmetric

Elements found in biological molecules

What are the major biomolecules?

• Carbohydrates• Protein• Lipids• Nucleic acds

Form of life

• Prokaryotes (bacteria, archae)• Unicellular• No nucleus• Lack internal membrane

systems• Incapable of carring complex

reactions

• Eukaryotes (animal, fungi)• Multicellular/ unicellular• Contain nucleus• Have membrane-bounded

cellular units• Capable to perform cpmplex

biological reactions (photosyntesis, aerobic metabolism etc.)

Representations of alanine

Representations of alanine

Structure of human endothelin

Illustration of entropy

How does evolution work?

Laboratory synthesis of biological molecules

Cyanobacteria

Prokaryotic cells

A eukaryotic cell

Evolutionary tree based on nucleotide sequences

Possible origin of eukaryotic cells