2. What is Biochemistry
Biochemistry is mother of different field in medicine
1.
2.
3.
4.
5.
6.
7.
8.
Anatomy
Physiology
Pharmacology
Genetic
Immunology
Bacteriology
Immunology
Parasitology
1.
2.
3.
4.
5.
6.
7.
Internal medicine
Surgery
Endocrinology
Dentistry
Psychology
Sociology
Nursing
3.
4. Definition of Biochemistry
“Chemistry of Life”
Living Things are composed of lifeless molecules
Doesn’t fully take into account what chemistry is
Biochemistry- Study of the structure, properties and
changes of bio-matter
5. Special Considerations
1. Complex and highly ordered
2. Everything has a function
3. Living things transform their environment
(extract energy)
4. Self-replicating
5. Reactions occur at constant temperature,
pressure and pH; in an aqueous environment
6. Biomolecules - Elements
C, H, O, N
99% of mass of most cells
P, S
Mg2+, Na+, K+, Ca2+, ClFe, Zn, Mn, Co, Cu
7. Biomolecules - Macromolecules
1. Carbohydrates- made up mostly of 7
monosaccharides
2. Proteins - 5 × 106, made up of 20 amino acids
3. Nucleic Acids - 1,000, made up of 4 nucleotides
4. Lipids
8. Water
•
•
70% of most organisms
polar
•
•
favors solubility
directionality holds macromolecules in given
conformations
12. Cell Membrane
Appears as 3 layers by EM
• 7.5-10 nm thick
• “Unit membrane”
These three things are explained on
a molecular level as a
phospholipid bilayer
Function: osmotic barrier
Present in all cells
Further consideration in lipid
material.
•
13. Nucleus
Bounded by a porous
nuclear membrane
Function: contain DNA
Present in all eukaryotic
cells
• 1 per cell
• Often 1-4 nucleoli
•
25. Golgi Apparatus
Historically cis, medial and
trans: trans-golgi network
Function: protein processing
and secretion
Present in all eukaryotic cells
(lots)
26. Lysosomes
About as big as a
mitochondrion
• not much to see
Function: degradation of
proteins
Present in animal cells, plant
cells have similar organelle
called peroxisome
Number per cell varies
enormously
•
27. Chloroplasts
Stacks of “grana”
• grana composed of
thylakoid disks
Function: photosynthesis
Present in photosynthetic
cells
50-200 per cell
•
48. Primary structure of protein:
the amino acid sequence
Primary structure is due to strong
covalent peptide bonds joining amino
acids together.
lysozyme
50. Secondary structure:
group of amino acids
folded repetitively to
make a discrete shape.
due to hydrogen
bonds between
amino acids’
backbones.
lysozyme
59. Water is Weakly Ionizable
•
•
•
•
2 H2O <===> OH– + H3O+
Weakly means this doesn’t happen often
[OH–] = [H3O+] = 1 × 10-7 M,
[OH–] × [H3O+] = 1 × 10-14, the basis of the pH
scale
63. Buffers
Buffer- a compound that does not allow the pH to
change even if acid or base is added to the system.
Amphiprotic compounds are also good buffers.
Amphiprotic compound- a compound that can act as
a proton donor or as a proton acceptor.
65. When pH = pKa’, There is Equal
Amounts of A– and HA
•
Proof on board
66. pH Problems
What will the pH of a solution be if 0.1 mL of 6 M
HCl is added to 100. mL of H2O?
What will the pH of a solution be if 0.1 mL of 6 M
HCl is added to 100. mL of 1 M HEPES initially
at pH 7.6?
What will the pH of a solution be if 0.1 mL of 6 M
HCl is added to 100. mL of 50 mM HEPES
initially at pH 7.6?
