CHEMISTRY The Chemical Basis of the Body

MATTER anything that has mass and occupies space solid - liquid - gas made up of ELEMENTS

Atoms the smallest unit of Matter the smallest unit of Matter two basic parts two basic parts –Nucleus –Electrons

Nucleus Protons (+ charge) Protons (+ charge) – # of protons = elements Atomic Number Neutrons (uncharged) Neutrons (uncharged) Charge of the Nucleus is + Charge of the Nucleus is + Electrons - negatively charged particles - orbit around the nucleus Electrons - negatively charged particles - orbit around the nucleus # of electrons always equals the # of protons in an atom # of electrons always equals the # of protons in an atom

Elements The building blocks of matter

Most Abundant Elements There are 26 elements in the body Most abundant are CHON 96% of total body mass O 2 is most abundant at 65%

Other Elements

Ions When an element loses or gains an electron Potassium( K+) and Sodium(Na+) are important ions Also called Cations and Anions

Electrolytes Ions in the fluids of the body Ions in the fluids of the body Essential to many processes in the body Essential to many processes in the body – Cell function – Cell signaling Can be lost through fluid loss Can be lost through fluid loss

Compounds Combination of two or more atoms The different elements seem to lose their individual characteristics

Chemical Bonding Formed when electrons are Gained, Lost, or Shared

Ionic Bonding Ionic Bonding One loses and one gains an electron One loses and one gains an electron Held together by the force of attraction Held together by the force of attraction Weakest type of chemical bonding Weakest type of chemical bonding

Covalent Bonding Sharing of electron pairs Single covalent bond = share one pair of electrons Stronger than ionic bonds – double covalent bond = share two pairs of electrons – triple covalent bonds = share three pairs of electrons

Hydrogen Bonds covalently bond with H and another element covalently bond with H and another element very weak bond (5%) very weak bond (5%) Easily broken Easily broken Essential to life Essential to life

Polar Bond Unequal sharing of electrons Property of water that aids in movement of water

pH Describes acidity or alkalinity (basicity) of a solution Describes acidity or alkalinity (basicity) of a solution Number of H+ ions or OH- ions in solution Number of H+ ions or OH- ions in solution Biochemical reactions - sensitive to small changes Biochemical reactions - sensitive to small changes Salt is a + and – charged ion bonded together. Salt is a + and – charged ion bonded together.

pH scale The first line of defense against disease is a proper pH balance Buffers act to maintain blood pH between 7.35 and 7.45 even though acids and bases are continually being added to and removed from the blood as it travels through the body

Water Polar molecule Universal solvent Adhesion & cohesion Surface Tension Transports substances Absorbs and releases heat slowly Aids in chemical reactions Forms saliva Lubricates joints Blood plasma is 92% water

Macromolecules Organic CompoundElementsBuilding Blocks CarbohydratesCarbon, Hydrogen and Oxygen Simple sugars (monosaccharides) LipidsCarbon, Hydrogen and Oxygen Glycerol and Fatty Acids ProteinsCarbon, Hydrogen, Oxygen, Nitrogen, Phosphorus and Sulfur Amino Acids Nucleic Acids (DNA and RNA) Carbon, Hydrogen, Oxygen, Nitrogen and Phosphorus Nucleotides

Carbohydrates Formula is C 6 H 12 O 6. Structural units in DNA and cell membrane MAJOR ENERGY SOURCE for the body. ONLY energy source for brain and nerve cells Blood sugar is known as glucose

Lipids (FATS) Insoluble in water Insoluble in water Important lipids in the body: Important lipids in the body: triglycerides, phospholipids and cholesterol Second source of energy Second source of energy Protects body organs Protects body organs Provides insulation and warmth Provides insulation and warmth Absorbs fat soluble vitamins Absorbs fat soluble vitamins Forms sex hormones and steroids Forms sex hormones and steroids

Proteins Building blocks called Amino Acids (20) Structure of body tissues Form enzymes which are catalysts Antibodies Regulate osmotic pressure in the blood Function as storage molecules

Proteins carry out a wide range of functions in the body: 1. Collagen & keratin are structural proteins. Collagen holds the tissues together throughout the body and strengthens ligaments and tendons. Keratin is a protein that toughens and waterproofs the skin. 2.Many hormones that regulate body functions are proteins. 3.The proteins actin and myosin permit our muscles to contract. 4. Hemoglobin is a blood protein that transports oxygen and carbon dioxide throughout the body. 5. Antibodies are proteins in the blood and body fluids that help to fight infections. 6. Enzymes are a special class of proteins that assist other chemicals to react with each other. These reactions are the basis of all life chemistry.

Nucleic Acids DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). Contains the atoms C,H,O,N AND P Contains the atoms C,H,O,N AND P DNA stores the genetic code on chromosomes DNA stores the genetic code on chromosomes DNA and RNA assist with protein synthesis DNA and RNA assist with protein synthesis Central Dogma Central Dogma

Structure of RNA RNA is formed by a single strand of nucleotides RNA is formed by a single strand of nucleotides RNA can leave the nucleus RNA can leave the nucleus Helps make proteins Helps make proteins Transfers amino acids for proteins Transfers amino acids for proteins

Adenosine-TriPhosphate (ATP) In all living systems Drives all chemical reactions Occurs through a process called cellular respiration ATP + H 2 0 ADP + P + ENERGY

The End! ATP is found in the Mitochondria ATP is found in the Mitochondria