Basic Chemistry

Chemistry

The study of matter and its interactions, relevant to anatomy and physiology.

Synthesis Reaction

A chemical reaction where two or more substances combine to form a new compound.

Decomposition Reaction

A chemical reaction where a compound breaks down into simpler substances.

Exchange Reaction

A chemical reaction where parts of two compounds swap places to form two new compounds.

Inorganic Molecules

Molecules that do not contain carbon-hydrogen bonds and are essential for various functions in the human body.

Organic Molecules

Molecules that contain carbon-hydrogen bonds and are vital for life processes.

Matter

Anything that occupies space and has mass.

Mass

The amount of matter in an object.

Weight

The gravitational force acting on an object of a given mass.

Elements

Fundamental units of matter, with 96% of the body made from four elements: Carbon (C), Oxygen (O), Hydrogen (H), and Nitrogen (N).

Bulk Elements

Elements required by the body in large amounts.

Trace Elements

Elements required by the body in small amounts.

Ultratrace Elements

Elements required by the body in very minute amounts.

Atoms

The smallest particle of an element.

Atomic Number

The number of protons in the nucleus of one atom, which equals the number of electrons in the atom.

Mass Number

The number of protons plus the number of neutrons in one atom.

Atomic Weight

The average of mass numbers of the isotopes of an element.

Isotopes

Atoms with the same atomic numbers but with different mass numbers due to a different number of neutrons.

Molecule

A particle formed when two or more atoms chemically combine.

Compound

A particle formed when two or more atoms of different elements chemically combine.

Molecular Formulas

Formulas that depict the elements present and the number of each atom present in the molecule.

Potential Energy

Stored energy, such as that in chemical bonds.

Kinetic Energy

The energy of motion, such as molecular movement.

Chemical Energy

Energy stored in chemical bonds.

Electrical Energy

Energy resulting from the flow of electrons.

Mechanical Energy

Energy associated with the movement of parts.

Radiant Energy

Energy in the form of waves of particles, such as light.

Thermal Energy

Energy in the form of heat, created by muscles during contraction.

Homeostasis

The maintenance of a stable internal environment in the body, requiring matter and energy.

Digestion

Chemical breakdown of food (compounds) into elements that can diffuse into or out of the cell membrane.

Nervous System

Movement of ions across membranes to conduct an impulse.

Muscular System

Energy used to conduct heat and move the skeleton.

Ionic Bonds

Form when electrons are completely transferred from one atom to another.

Polar Covalent Bonds

Unequal sharing of electrons between two atoms resulting in a slightly positive charge on one side and slightly negative charge on the other side.

Nonpolar Covalent Bonds

Equal sharing of electrons between two atoms resulting in an even charge distribution.

Hydrogen Bonds

Weak chemical bonds where hydrogen is attracted to the negative portion of a polar molecule, providing attraction between molecules.

Chemical Reactions

Processes that form or break chemical bonds between atoms, converting reactants to products.

Reactants

Substances that undergo chemical reactions.

Products

Substances that are formed as a result of a chemical reaction.

Exergonic Reaction

Releases energy; reactants contain more energy than products.

Endergonic Reaction

Require an input of energy; products contain more energy than reactants.

Synthesis Reaction

Atoms or molecules combine, absorbing energy for bond formation; example: amino acids bond to form proteins.

Decomposition Reaction

Molecule is broken down, releasing chemical energy; example: ATP loses a phosphate, releasing energy.

Reversible Reaction

Reaction that can run in an opposite direction, converting products back to the original reactants.

Exchange Reaction

Chemical bonds are broken and new bonds are formed.

Equilibrium

Rate of product formation is equal to the rate of reactant formation, keeping the amount of reactants relative to products constant.

Acid

A substance that releases hydrogen ion; proton donor; example: Hydrochloric acid in the stomach.

Base

Proton acceptor; example: Sodium hydroxide.

pH Scale

A measure of hydrogen concentration of a solution.

Neutral Solution

Equal number of hydrogen and hydroxide ions; pH is 7.

Acidic Solution

Greater concentration of hydrogen ions; pH < 7.

Basic Solution

Greater concentration of hydroxide ions; pH > 7.

Acidosis

A condition with a blood pH below 7.35; can cause disorientation, coma, or death due to depressed nervous system.

Alkalosis

A condition with a blood pH above 7.45; can cause nervousness, convulsions, or death due to overly stimulated nervous system.

Catalyst

A substance that increases the rate of chemical reaction without being permanently changed or depleted.

Enzymes

A protein molecule that acts as a catalyst, employed to catalyze chemical reactions in cells.

Active Site

A pocket on an enzyme where reactants (substrates) bind.

Substrates

Reactants that bind to the active site of an enzyme.

Three Steps of Enzyme Catalysis

1. Substrates enter the active site in a specific orientation. 2. Upon binding, the substrates and enzyme change shape to promote a reaction.

Enzyme

A given enzyme usually catalyzes a single step in a chain of metabolic reactions.

Buffer

A chemical that resists the change in pH when either an acidic or a base is added.

Buffer Function

The buffer binds to the acid or base preventing the ions from causing a decreased or increased in the pH of the solution.

Inorganic Molecules

A substance that does not contain carbon; except carbon dioxide and carbon monoxide.

Inorganic Molecules Role

Play many vital roles in human anatomy and physiology.

Examples of Inorganic Molecules

Oxygen, Carbon dioxide, water.

Oxygen

Small, nonpolar molecule, consisting of two oxygen atoms bound by a double covalent bond.

Oxygen in Atmosphere

21% of the atmospheric gas.

Oxygen Requirement

Needed in humans for the final step in the series of chemical reactions.

Carbon Dioxide

Consists of one carbon atom bound to two oxygen atoms by a double covalent bond.

Carbon Dioxide Production

Produced when food molecules are metabolized within the cells of the body.

Carbon Dioxide Elimination

Eliminated from the cell as a metabolic by-product; transferred to the lungs by the blood and exhaled during respiration.

Carbon Dioxide Toxicity

Toxic when accumulated.

Water

Most abundant inorganic compound; 67% of body weight.

Water Polarity

Water is polar.

Water as Solvent

Good solvent- able to dissolve many substances if they are polar.

Water Surface Tension

Water molecules adhere to one another across its surface.

Water Capillarity

Water will rise up in a tube due to cohesion and adhesion.

Water Properties

Stabilizing body temperature, Providing protection, Facilitating chemical reactions, Transporting substances.

Organic Molecules

Carbon containing substances bounded by covalent bonds.

Organic Molecules Framework

Constitutes the framework of many large molecules.

Organic Molecules Mechanisms

Variation in the length of the carbon chain and Combination of the atoms bound to the carbon framework.

Essential Organic Molecules

Carbohydrates; Lipids; Proteins; Nucleic acids.

Carbohydrates Composition

Contain carbon, hydrogen, and oxygen in roughly a 1:2:1 ratio.

Carbohydrates Classification

Include sugars and starches; Classified according to size.

Monosaccharides

Simple sugars.

Disaccharides

Two simple sugars joined by dehydration synthesis- removal of water to form a bond.

Polysaccharides

Long branching chains of linked simple sugars.

Lipids Composition

Contain carbon, hydrogen, and oxygen; Carbon and hydrogen outnumber oxygen.

Lipids Monomers

Monomers are fatty acids and glycerol.

Lipids Solubility

Most are insoluble in water and non-polar; Some have polar heads.

Saturated Lipids

All single bonds; Solids at room temp; Animal fats; 'Pile up' on sides of vessels.

Unsaturated Lipids

Some double bonds; Liquids at room temp.

Plant fats

Organic Molecules - Lipids

Neutral fats

Composed of 3 fatty acids and glycerol; Source of stored energy

Phospholipids

Form cell membranes; Composed of: 2 Fatty acids; Glycerol; Phosphate head

Steroids

3 interlocking 6-C rings, a 5-C ring, and a fatty acid chain

Examples of Steroids

cholesterol, bile salts, vitamin D, and some hormones

Building blocks of fat

glycerol and fatty acids

Proteins

Building blocks are amino acids

Amino acids

Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur