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