Biology

1. BIOLOGY FOR ENGINEERING
APPLICATIONS
Maheswaran Easwaran
Assistant Professor (Sr. G)
Department of Biomedical Engineering

2. • Genetics
• Bio molecules
• Biological Applications in
Engineering
• Nervous System

3. GENETICS AND BIO-MOLECULES (Basics only)
 Basics of Genes
 DNA structure
 Genes and hereditary
 Genetic Code
Coding and decoding
Genetic information
 Gene Mapping
 Gene Interactions
 Mutations
 Genetic disorders
 Gene therapy

4. Basics of Gene

7. Genetics
• Field of biology
• Study - how traits are passed
• basic components of genetics
• DNA/RNA
• Hold all the genetic information
• Diagnose, treat, prevent and cure many illnesses.

8. What are Genes?
• In 1865, Gregor Mendal - describe the
elements of heredity.
• Greek - ‘to become’ or ‘to grow into’.
• Genes, which are made up of DNA, acts as
RNA instructor to make molecules - Proteins.

11. The central dogma of molecular biology
two-step process - transcription and translation
DNA → RNA → protein.
Flow of genetic information

12. • The lettersA, G, T and
C correspond to the
nucleotides found in
DNA.
• organized into codons.
• Collection of
codons - Genetic
code.
• 20 amino acids
• Codon - 3 nucleotides

13. Genetic Code
• Set of rules used by living cells
• To translate information
• Encoded within genetic material into
proteins

14. Genetic Code

16. Initiator codon
⚫AUG is the initiator codon in majority
of proteins
⚫In a few cases GUG may be the
initiator codon
⚫Methionine is the only amino acid
specified by just one codon,AUG.

17. Non Sense Codons
⚫ 3 codons - 64 in genetic code
⚫ Termination codons or stop codons
⚫ nonsense codons
⚫ UAA, UAG, and UGA.
⚫ No amino acid.
⚫ The ribosome pauses

18. Non Sense Codons

20. Clinical Significance
⚫Mutations can be well explained using
the genetic code.
Mutations
1) Silent
2)Misense
3)Nonsense
Frameshift

21. Silent Mutations
Single nucleotide change-Ato G, same
amino acid is incorporated. Mutation goes
unnoticed.

22. Missense mutations
Single nucleotide change A to C – different amino
acid incorporated. Loss of functional capacity of
protein.

23. Non sense Mutation
Single nucleotide change from C to T, stop codon is
generated (In m RNA represented by UAG), premature
termination of chain, may be incompatible with life.

24. Frame sift Mutations
⚫ Insertion or removal of a base/bases can alter the
reading frame with the resultant incorporation of
different amino acids

25. CARBOHYDRATES

26. Carbohydrates:

34. Fatty acids

39. Nucleic Acids

40. Introduction:
• Large biomolecules
• Essential – life
• Bac, Virus., Mitocon.,
• Encode and Store information
• Express – information

47. PROTEIN

48. Central dogma of molecular biology
Translation (inside the
ribosome (with help of
tRNA):
Translation: making a
peptide using mRNA as
the coding template
(peptide synthesis)
mRNA… messenger RNA
tRNA … transfer RNA
mRNA

53. The structure of proteins
1° structure: Amino acid sequence
–Twenty amino acids common to all organisms.
–Each has amino group, carboxyl group, R group
and a hydrogen
–Linked together by peptide bond.

54. The structure of
proteins
Alpha helix:
- right-handed helix
-100° rotation (twist)
- 3.6 residues/turn
-stabilized by H-bonds
between NH and CO group
(four residues up).
2° structure: alpha helix
-helix
(© by Irvine Geis)
Biochemistry Voet & Voet
Red – oxygen
Black – carbon
Blue – nitrogen
Purple – R-group
White – C
Hydrogen-bonds between C-O of nth
and N-H group of n+4th residue.

55. PHYSICAL PROPERTIES OF PROTEINS
Protein solutions exhibit colloidal properties
Molecular weights
Insulin (5,700); Hemoglobin (68,000);
Albumin (69,000); Immunoglobulins (1,50,000)
Shape: Insulin is globular, Albumin is oval in shape,
Fibrinogen molecule is elongated.

56. Classification Based on Functions
1. Catalytic proteins, e.g. enzymes
2. Structural proteins, e.g. collagen, elastin
3. Contractile proteins, e.g. myosin, actin.
4. Transport proteins, e.g. hemoglobin, albumin, transferrin
5. Regulatory proteins or hormones, e.g. ACTH, insulin
6. Genetic proteins, e.g. histones
7.Protective proteins, e.g. immunoglobulins, interferons,
Clotting factors.

57. Thank you!