Chemical Basis of life Part 1:
Organic components of life
Ms. Celeste Roderno-Desingaño
CARBOHYDRATESCompounds composed
of C,H,O
Carbohydrates literally means hydrate of carbon or carbon plus water.
The chief energy sources for cellular activities within the cell.
Excess carbohydrates are converted to glycogen and fat.
Types of Carbohydrates1. Simple Sugar
(Monosaccharide) Ex. Glucose
Galactose Fructose Ribose Deoxyribose
2. Double Sugar (Disaccharide) Ex. Maltose (glu-
glu), Lactose (glu-gal), Sucrose (glu-fruc)
3.Complex Sugar (Polysaccharide) Ex. Starch
Glycogen CelluloseChitin
PROTEINSBody is composed of 50%
protein.
Contains C,H,O,N and some contain P and S.
Amino acids are the building blocks of proteins composed of amino group (-NH2) on one end and a carboxyl group (-COOH) on the other.
20 essential amino acids
Ex. Collagen, hemoglobin, myosin, albumin, found in the hair, nails, claws and enzyme
Functions/Benefits:Support and structure---making
up the fibers found in skin, bone, tendons, nails, claws, hair and the like.
Movement ----major component of muscles and are responsible for muscle contraction
Transport ----function in oxygen transport and as hormones
Disease defense --- immune response.
Catalyst of biological reactions.
LIPIDSComposed of C,H,O
but may contain other elements, particularly phosphorus and nitrogen
Insoluble in water but soluble in organic solvents such as benzene, ether and chloroform
Function:Energy storageChemical
messengers like hormones
Types of Lipids
1. Simple LipidsA. Triglyceride Energy storage molecules in living
organisms.Provide insulation, cushioning and
protection for various parts of the body
Building block compounds : alcohol and fatty acid.
Ex: Fats (saturated) and Oil (Unsaturated)
B. Waxes Secreted to the outer surface of cell
walls Secreted by modified sweat glands
in our ears
Types of Lipids2. Compound Lipids
A. PhospholipidsLipids with phosphate
groupMajor constituent of cell
membraneEx: Lecithin, Cephalins,
Plasmalogens, Lipositols and Sphingomyelins
B. GlycolipidsEx: Cerebrosides,
gangliosides, sulfolipids and proteolipids
C. TerpenoidsFound in essential oils,
resin acids, rubber, plant pigmets such as carotene and lycopene, camphor and vitamins.
D. SteroidsEx: Cholesterol (HDL and
LDL), androgen and estrogen hormones, corticosteroids
3. Derived LipidsDerived from hydrolysis of
simple and complex lipidsEx: Fatty acids: Omega 3
and Omega 6
NUCLEIC ACID
The building block unit is the nucleotide, made up of 5-C sugar attached to a phosphate group and to a nitrogen-containing base.
Types of Nucleic Acid1. Deoxyribonucleic
Acid (DNA)
The building blocks of DNA are: deoxyribose, nitrogen bases and phosphate group.
Double stranded coiled into a double helix.
The two strands are held together by hydrogen bonds between adjacent bases.
Each ring must be composed of purine and pyrimidine (pairing is specific).
NITROGEN BASES
Types of Nucleic Acid2. Ribonucleic Acid
(RNA)
Types of RNA 1. mRNA act as messengers
carrying instructions from DNA genes to the ribosome, bodies that are the sites of protein synthesis in the cell.
2. rRNA are structural component of the ribosomes.
3. tRNA transports amino acids to those ribosomes for assembly into proteins.
Differences between DNA and RNA1. The pentose sugar of RNA is ribose
instead of deoxyribose in DNA
2. One of the four nitrogen bases of DNA is thymine. In RNA instead of thymine it contains a very similar base called Uracil.
3. RNA is ordinarily single-stranded , whereas DNA is double-stranded.
Chemical Basis of life Part 2:
INORGANIC COMPONENTS OF LIFE
WATERMost important component of
tissues about two-thirds of body weight
Medium in which all of the physiological activities necessary for life take place
FunctionsTransport food and remove
waste material Metabolic breakdown of
proteins and carbohydrates (hydrolysis)
Often a reactant or a product of chemical reactions
Properties of WaterPolar compoundUniversal solventPure water is odorless
and tastelessFreezing pt. Boiling pt.Good conductor of heat
and electricity
ACID and BASESvante Arrhenius(1859-1927)Arrhenius Theory
Johannes Nicolaus Brønsted (1879–1947) Thomas Martin Lowry (1874-1936) Bronsted-Lowry Theory
Acids are substances which produce hydrogen ions in solution.
Bases are substances which produce hydroxide ions in solution.
An acid is a proton (hydrogen ion) donor.
A base is a proton (hydrogen ion) acceptor.
ACID and BASEGilbert Newton Lewis(1875-1946) Lewis Theory
pHAn acid is an electron
pair acceptorA base is an electron pair
donor.
pondus hydrogenii, potentia hydrogenii (Latin)
potentiel hydrogène (French)
potential of hydrogen (English)
It is a measure of the acidity or alkalinity of a solution.
ACIDAqueous solutions with a
pH less than seven are considered acidic.
Contains hydronium (H+) ion and is often used as a synonym for H3O+.
Examples include acetic acid (vinegar) and sulfuric acid (used in car batteries)
effect of an acid is to increase the hydronium ion (H3O+) concentration in water
PROPERTIES OF ACIDTaste: Acids generally have a
sour taste
Touch: Strong or concentrated acids often produce a stinging feeling on mucous membrane
Reactivity: Strong acids react aggressively with or corrode many metals
Electrical conductivity: Acids, while not usually ionic compounds, are electrolytes
Litmus Reaction: Acids turn moist blue litmus paper red
BASE/ALKALINESolution with a pH
greater than seven are considered basic (alkaline).
Contains hydroxide (OH-) ion
Examples of simple bases are Sodium hydroxide and ammonia
Bases can be thought of as the chemical opposite of acids.
Bases reduce hydronium ion concentration
PROPERTIES OF BASESTaste: Bitter taste
Touch: Slimy or soapy feel on fingers
Reactivity: Caustic on organic matter, react violently with acidic substances
Electric conductivity: Aqueous solutions or molten bases dissociate in ions and conduct electricity
Litmus Reaction: Bases turn red litmus paper blue
NEUTRALIZATION
BUFFER
Formed by combining acid and base
Product of neutralizationSALT and WATER
An ionic compound that resists changes in its pH.
An aqueous solution consisting of a mixture of a weak acid and its conjugate base or a weak base and its conjugate acid.
SALT and ELECTROLYTESalts dissolved in water are called electrolytes Electrolytes are substances that becomes ions
and acquire the capacity to conduct electricity. Muscle tissue and neurons are activated by
electrolyte activity Ex. Ca2+, Na+, K+Loss of electrolyte leads to dehydration