Chemical level of Organization
Lecture content:
1.
2.
3.
4.
5.
6.
7.
8.
Organization of matter
Structure of Atom
Ions, molecule and compounds
Types of chemical reactions
Solution, colloids & suspension
Concept of pH
Organic compounds
Nucleic acid: DNA & RNA
1.
Organization of Matter
Living things consists of matter
Matter is defined as any thing that occupies space and has a
mass. A chemical element consists of Atom.
Atom is the smallest unit of matter that maintains the character
of an element Atom consists of Proton, Neutron and electron
2. Structure of Atom
Atomic number: Number of protons in the nucleus of an atom
Atomic mass: is the number of protons and neutrons in the
nucleus
Isotope: Atom that has different mass number
Radioactive isotopes: Unstable isotopes are called radio active
isotope.
3. Ions , molecules and compounds
Ions: An atom when gives up or gains electron , it becomes an
ion
An ion can be +ve positively charged or –ve negatively
charged
+ve ion is called Cation and –ve ion is called Anion
Molecules: When two or more atoms share electron, it
becomes molecule
Compounds: A subs tance that can be broken down to 2 or
more different
Elements- like H2O, NaCl.
A compound must have atom of more than one element
4. Types of Chemical reaction:
Anabolism: endergonic reaction: absorb more energy
Catabolism: Exergonic reaction: release more energy
5. Solution, Colloid & Suspension
Acid: a substance that dissociate into one or more H+ ion
It is a Proton donor
Base: dissociate into one or more OH- . It is Proton acceptor
Salt: A substance in solution dissociate into Cation & anion
NaCl- Na+ + ClCommon mixtures: Solution
Colloidal solution
Suspension
6. Concept of pH
pH of body fluid generally vary within very narrow limit.
PH of blood is between 7.35 to 7.45
Maintained by blood buffer systems:
a. bicarbonate buffer
b. phosphate buffer
c. protein buffer (Hemoglobin)
7. Organic compounds
Carbohydrate: Monosaccharides
Disaccharides
Polysaccharides
Lipids: Monounsaturated fat
Saturated fat
Steroids, Fatty acids
Eicosanoids: Prostaglandin, Leukotriene
Organic compounds (continue)
Proteins: Functions of proteins
a. Structural
b. Regulatory
c. Contractile
d. Immunological
e. Transport
f. Catalytic
Protein contains C,H,O,&N in the form of amino acid, dipeptide &
Polypeptides
8. Nucleic acid: Deoxyribonucleic acid (DNA)
Ribonucleic acid (RNA)
Nucleic acids are of 2 varieties: DNA & RNA
DNA: form the genetic material in each cell
Gene is a segment of DNA molecule
RNA: relays instructions from gene to guide protein synthesis in each
cell.
Structure of DNA: Nucleotide unit : each nucleotide unit consists of
a. Nitrogenous bases: adenine, guanine, thiamine
& cytocine
b. Pentose sugar
c. Phosphate group