2. By Dr. Elrasheed Eltaher Osman

3. Biochemistry
Definition
Is the science concerned
with various biomolecules
that occur in the living cell
and organism and their
chemical reactions

4. Components of biochemistry :
1- cell biology
2- molecular biology
3- molecular genetics

5. Aims of biochemistry
1- is to describe and explain in
molecular terms all chemical
processes of living cell
2- To understand how life is began
3- knowledge of biochemistry is
essential to all life sciences

6. Bio-medicine relationship
 Most Biomedical of biomedical
techniques
reaction used for has diagnosis been
of
discovered diseases
after following
a course of a disease
 All diseases have
biomedical bases
Biochemistry used for
formulation of drugs

7. In order to study biochemistry a little
information should be known about
the cell
The cell smallest unit of live capable
of doing all living processes
Cell divided into :
1- eukaryotic cell
2- prokaryotic cell

9. Biomolecules
Complex molecules that is formed living
organisms they include:
1- carbohydrates
2- protein
3- lipids
4- nucleic acids
5- minerals
6- vitamins
7- water

10. All are composed of atoms
 All except minerals contain
elements of water
 All except minerals and water
are organic molecules
 All except minerals ,water and
vitamins yield energy

11. • WATER IS BLESS FROM GOD
~ USE IT DON’T ABUSE IT

12. Homeostasis
Is the maintenance of composition of the
internal environment for good health and
this include:
1- water distribution
2- pH
3- electrolytes concentration

13. WATER , pH and BUFFERS
Water
Is the principle end product of
oxidative catabolism of food
Is the most important molecule
for life
No life without water
All elements and processes in
some how needs water

14. Water distribution
This depends on
Control of thirst by hypothalamus
Anti-diuretic hormone
Retention or excretion of water by
-Kidney (micturition)
- skin (perispiration)
-Lung (respiration)

15. Water disbalance
occurs when there is state of water
depletion or excess
Water depletion (dehydration)
Result from
1- decrease intake (comma)
2- increase loss (severe
sweating, renal loss, diarrhea
cholera …

16. Water excess
May be due to:
 Increase intake
(excessive I/V fluids)
 Decrease output
(renal failure)

17. WHAT MAKES WATER AN
IDEAL SOLVENT FOR THE
LIFE ?
This is due to its ideal
properties

18. Physical properties of water
1- high heat of vaporization
2- high melting
3- low freezing point
4- neutral pH

19. solvent Melting
point
Boilin
g
point
Heat of
vaporizatio
n
1 water 0 100 2260
2 methanol -98 65 1100
3 ethanol -117 78 854
4 acetone -95 56 523
5 benzene 6 80 394
6 chloroform -63 61 247
7 Hexane -98 69 423

20. Chemical properties of water
1- tetrahedral
2- bipolar
3- formation of hydrogen bonds
4- Partial dissociation
5- React as acid or base
6- high ionic product

21. pH
Potential hydrogen
Hydrogen ion concentration
Is –log [H+]
pH scale 1—14
7 neutral
Normal pH 7.35 – 7.45

22. • pH < 7 acidic
• In blood pH<7.35
acidosis
•Acidosis can be
1- metabolic
2- respiratory

23. • pH > 7 alkaline
• In blood pH>7.45
alkalosis
• Alkalosis can be
1- metabolic
2- respiratory

24. Buffers
 Molecules that resist
change in pH when acid
or alkaline are added to a
solution
 They are week acids
and their conjugated
base

25. Normal occurring buffers
inside human body include:
1- carbonic acid and
bicarbonate
2- organic phosphoric acid
and phosphate
3- proteins

26. Week acid
HX H++X-Conjugate
base
AX A++X-

27. If we add acid
(H+)
+ H+
H+
HX H++X-H
AX A+ + X-

28. Not like this
Wake up

29. Forces stabilizing bimolecules
These Include:
1- covalent bonds
2- non- covalent bonds

30. Covalent bonds
 Strong bonds
 Needs high energy to be broken
 Examples are
Peptide bonds
Glycosidic bonds
Ester bonds
Disulfide bridge

32. Peptide bonds
 Covalent bond
 Form between amino group
of one molecule and carboxyl
group on another molecule

34. Glycosidic bond
 Covalent bond
 Form between two different
alcohol groups
 Can be
1- N-glycosidic
2- O-glycosidic
3- S-glycosidic

36. O-glycosidic bond
Occur when the two
alcoholic groups are
OH-

37. -CH2OH + OHCH2-
-CH2-O-CH2- H2O

38. N-glycosidic bond
Occur when one
of the alcohol
group is NH3

39. -CH2NH2 + OHCH2-
-CH2-N-CH2- H2O
IH

40. S-glycosidic
Occur when one
of the alcohol
group is SH

41. -CH2SH + OHCH2-
-CH2-S-CH2- H2O

42. Ester bond
Occur between alcohol
group and carboxyl group
Phosphoester
Thioester

44. 2O
-COH +H OOC-H
II
-C-O-C-O

45. Disulfide bridge
Occur between two SH
group

46. 2H+
-SH + HS-
―S―S―

48. The non-covalent bonds
This include
1- hydrogen bond
2- hydrophobic interaction
3- Electrostatic bond
4- Van Der Waal forces

49. Hydrogen bond
 Non-covalent bond
 Occur between positive
hydrogen ion in a molecule ad
negative ion in another one
Is very week bond

52. The hydrophobic interaction
Is tendency of a molecule for
folding around it self to hide
the non-polar part from water
when put in solution
In this case the polar
part come to the out side
to contact water

54. Electrostatic interaction
(ionic bridge,salt bridge)
 Non-covalent bond
 Occur between a positive
ion in one molecule and most
negative ion in another
molecule

56. Van Der Waal forces
Is the attractive and
repulsive forces that
occur between two
adjacent atoms in a
molecule