biochemistry

1. Lecture 1
Introduction to Biochemistry
Introduction to biochemistry
AMNU 214

2. Introduction
 What is the Biochemistry?
 History and development
 How to study Biochemistry?

3. 1. Biochemistry
 Definition: The chemistry of life
 The science concerned with the chemical
basis of life.
 The science concerned with the various
molecules that occur in living cells and
organisms and with their chemical reaction.

4. Biochemistry
 Aim: to describe and explain, in
molecular terms, all chemical
processes of living cells
 Structure-function
 Metabolism and Regulation
 How life began？

5. Biochemistry
 Significance: be essential to all life
sciences as the common knowledge
 Genetics; Cell biology; Molecular biology
 Physiology and Immunology
 Pharmacology and Pharmacy
 Toxicology; Pathology; Microbiology

6. 2. History and development of
Biochemistry
1903, Neuberg (German):
“Biochemistry”
“Chemistry of Life”
For information only

7. Two notable breakthroughs
(1) Discovery of the role of enzymes
as catalysts
(2) Identification of nucleic acids as
information molecules
Flow of information: from nucleic acids to proteins
DNA RNA Protein
For information only

8.  In 1937， Krebs for the discovery of the
Citric Acid Cycle-won the Nobel Prize in
Physiology or Medicine in 1953
 In 1953，Watson & Crick for the discovery
of the “DNA Double Helix” -won the Nobel
Prize in Physiology or Medicine in 1962
Some historic events
For information only

9. 3.What dose the Biochemistry discuss?
 structure and function of cellular
components
 proteins, carbohydrates, lipids, nucleic
acids and other biomolecules
 Metabolism and Regulation
 Gene expression and modulation
DNA RNA Protein

10. Polymers and Monomers
 Each of these types of molecules are
polymers that are assembled from
single units called monomers.
 Each type of macromolecule is an
assemblage of a different type of
monomer.

11. Macromolecule
Carbohydrates
Lipids
Proteins
Nucleic acids
Monomer
Monosaccharide
Not always polymers;
Hydrocarbon chains
Amino acids
Nucleotides

12. How do monomers form polymers?
 In condensation
reactions (also
called dehydration
synthesis), a
molecule of water
is removed from
two monomers as
they are connected
together.

14.  Building block
 Simple sugar
 Amino acid
 Nucleotide
 Fatty acid
 Macromolecule
 Polysaccharide
 Protein (peptide)
 RNA or DNA
 Lipid
Anabolic
Catabolic

15. 4. Cells
 Basic building blocks of life
 Smallest living unit of an organism
 A cell may be an entire organism (unicellular)
or it may be one of billions of cells that
make up the organism (multicellular).
 Grow, reproduce, use energy, adapt, respond
to their environment
 Many cannot be seen with the naked eye
 a typical cell size is 10µm; a typical cell mass is
1 nanogram.)
For information only

16. •Cell membrane & cell wall
•Nucleoid region contains the DNA
•Contain ribosomes (no membrane)
• Cell Membrane
• Nucleus
• Cytoplasm with organelles
For information only

17. For information only

18. Characteristic Bio-membranes and Organelles
• Mitochondria- the power generators
Mitochondria : Surrounded by a double membrane with
a series of folds called cristae. Functions in energy
production through metabolism. Contains its own DNA.
•Plasma Membrane-Cell’s defining boundary
Providing a barrier and containing
transport and signaling systems.
•Nucleus – Cell’s information center
Double membrane surrounding the chromosomes and
the nucleolus. The place where almost all DNA
replication and RNA synthesis occur. The nucleolus is
a site for synthesis of RNA making up the ribosome
For information only

19. •Rough endoplasmic reticulum (RER)
Covered with ribosomes (causing the "rough"
appearance) which are in the process of
synthesizing proteins.
•Ribosomes
Protein and RNA complex responsible for
protein synthesis
•Smooth endoplasmic reticulum (SER)
A site for synthesis and metabolism of lipids.
Endoplasmic reticulum (ER) – The transport network for molecules
For information only

20. •Cytoplasm
enclosed by the plasma membrane, liquid
portion called cytosol and it houses the
membranous organelles.
•Lysosomes-contain digestive enzyme
A membrane bound organelle that is
responsible for degrading proteins and
membranes in the cell.
•Golgi apparatus
A series of stacked membranes. Vesicles
carry materials from the RER to the Golgi
apparatus. the proteins are "processed" to a
mature form.
For information only

21. 5. Biomolecules
 Just like cells are building blocks of tissues,
biomolecules are building blocks of cells.
 Animal and plant cells contain approximately
10,000 kinds of biomolecules.
 Water constitutes 50-95% of cells content
by weight.
 Ions like Na+, K+ and Ca2+ may account for
another 1%.
 Almost all other kinds of biomolecules are
organic (C, H, N, O, P, S).
 Organic compounds are compounds composed
primarily of a Carbon skeleton.

22. Carbon can form immensely diverse
compounds, from simple to complex.
Methane with 1
Carbon atom
DNA with tens of Billions
of Carbon atoms

23. Biomolecules
are
compounds
of carbon
with a variety
of functional
groups

24. Types of biomolecules
 Small molecules:
 Lipid, phospholipid, glycolipid, sterol,
 Vitamin
 Hormone, neurotransmitter
 Carbohydrate, sugar
 Monomers:
 Amino acids
 Nucleotides
 Monosaccharides
 Polymers:
 Peptides, oligopeptides, polypeptides, proteins
 Nucleic acids, i.e. DNA, RNA
 Oligosaccharides, polysaccharides (including
cellulose)

25. Chemical composition of a normal man
(weight 65 kg)
Constituent Percent (%) Weight (kg)
Water 61.6 40
Protein 17.0 11
Lipid 13.8 9
Carbohydrate 1.5 1
Minerals 6.1 4

26. Structural hierarchy in the molecular organization of cells

27. Similarities among all types of cells
 All cells use nucleic acids (DNA) to store
information
 Except RNA viruses, but not true cells
 All cells use nucleic acids (RNA) to access
stored information
 All cells use proteins as catalysts (enzymes) for
chemical reactions
 Different types of lipids in different types of cells
 All cells use carbohydrates for cell walls (if
present), and energy generation

28.  Carbohydrates
 Lipids
 Proteins
 Nucleic Acids
1. You are
expected to learn
the structure and
functions of these
organic compounds:
How much biochemistry do you need to
know for this course?
2. You will be expected to learn the basic
biochemical processes of major cell
functions, such as respiration, protein
synthesis and so on.