Chemistry of Life

n Matter -- anything that has MASS and takes up SPACE n EVERYTHING is made of matter

Chemistry of Life n Atoms – the SMALLEST particle that can exist and still be considered matter n All LIVING and NONLIVING things are made of atoms

Atoms -- have three components n ELECTRONS -- negatively charged n PROTONS -- positively charged; found in nucleus n NEUTRONS -- neutral; found in nucleus

Electrons Nucleus Protons & Neutrons Energy Levels

Chemical Reactions n Chemical reactions occur when bonds are FORMED or BROKEN. n This causes them to recombine into different substances.

Chemical Reactions n Metabolism –All reactions that occur in an organisms. n These reactions break down and build molecules important to life.

Chemical Reactions n Mixture: –A combination of a substance in which the individual components contain their own property.

Chemistry of the Cell n Solution: –A mixture in which one or more substances are distributed evenly in another substance. Solvent: A substance that can dissolve other substances Solute: The substance that is dissolved

pH n Chemical reactions also depend on the pH of the environment within the organism. n pH- –A measure of how acidic or basic a solution is.

pH n The scale goes from 0-14 –0 being the most acidic –14 being the most basic

Chemistry of Life n Elements -- a substance that is made of only ONE kind of ATOM

Reading Periodic Table Element Atomic Number Symbol

The Human Body

Major Elements of Life n C = Carbon n H = Hydrogen n O = Oxygen n P = Phosphorus n K = Potassium

Major Elements of Life n I = Iodine n N = Nitrogen n S = Sulfur n Ca = Calcium

Major Elements of Life n Fe = Iron n Mg = Magnesium n Na = Sodium n Cl = Chlorine

Chemistry of Life n Compounds – matter that is made of more than one kind of ATOM n Compounds are made by atoms sharing or taking ELECTRONS from other atom

Inorganic Compounds n Water ( H 2 O ) n Each molecule is made of two HYDROGEN atoms and one OXYGEN atom

Water –H 2 0

Why is water so important to agriculture? n At least 75% of animal body mass is water n Plants contain 70-80% water n Transports nutrients and wastes

Why is water so important to agriculture? n Dissolves compounds -- “Universal Solvent” n Regulates body temperature in animals n Provides structure for plants

Organic Compounds n Organic Compounds contain carbon. n Carbon forms the structural backbone of all living things.

Carbohydrates n Organic Compounds that contain: –Carbon –Hydrogen –Oxygen n They provide energy

Carbohydrates n Three Types –Monosaccharides –Disaccharides –Polysaccharides

Carbohydrates n Monosaccharides –simple SUGAR –contain C 6 H 12 O 6 –GLUCOSE, FRUCTOSE, AND GALACTOSE

Carbohydrates n Disaccharides –double SUGAR –contain two RINGS –SUCROSE and LACTOSE

Carbohydrates n Polysaccharides –complex CARBOHYDRATES –made of RINGS of SUGAR –STARCH, CELLULOSE, and GLYCOGEN

Proteins n Basic building material for all living things. n Used for STRUCTURE and FUNCTION n Made of H, O, C, N

Structure of Proteins n Amino Acids – building BLOCKS –20 different kinds – all have the same elements but in different amounts n Polypeptides – chains of AMINO ACIDS Joined by peptide bonds n Proteins – chains of POLYPEPTIDES n Used to make SKIN, HAIR, MUSCLE, ORGANS, etc.

Lipids n FATTY molecules n used to store ENERGY n Made of long chains of H & C followed by COOH n Do not DISSOLVE in WATER n Lipids have less OXYGEN than carbohydrates n Examples of Lipids are: FATS, OILS, AND WAXES

Nucleic Acids n Store INFORMATION that controls CELL activities n Made of a PHOSPHATE a SUGAR, and a BASE.

Examples of Nucleic Acids are: n DNA : –Deoxyribonucleic Acid n The master copy of an organisms information code. n Instructions to form all of an organisms structural proteins

Examples of Nucleic Acids are: n RNA : –Ribonucleic Acid n This forms a copy of the DNA for use in making protein.

Atoms are the building block of life!