Fundamentals of Anatomy & Physiology Eleventh Edition Chapter 2

Flashcards from the Fundamentals of Anatomy & Physiology Eleventh Edition Chapter 2 Lecture

Chemistry

Science that deals with the structure of matter, including the structure of atoms and how atoms combine.

Matter

Anything that takes up space and has mass; made up of atoms.

Atoms

Join together to form chemicals with different characteristics, which determine molecular and cellular physiology.

Protons

Positive charge, 1 mass unit.

Neutrons

Neutral, 1 mass unit.

Electrons

Negative charge, low mass.

Atomic number

Number of protons in an atom.

Nucleus

Contains protons and neutrons.

Electron cloud

Spherical area that contains electrons.

Electron shell

Two-dimensional representation of electron cloud.

Element

Pure substance composed of atoms of one kind.

Isotopes

Versions of elements based on the mass number (number of protons plus neutrons).

Radioisotopes

Have radioactive nuclei; decay rate is expressed as half-life.

Atomic weight

Average of the different atomic masses and proportions of different isotopes.

Mole (mol)

Weight in grams equal to the atomic weight of the element.

Electrons and Energy Levels

Electrons in the electron cloud that determine the reactivity of an atom.

Valence shell

Outermost shell that determines bonding.

Molecule

Two or more atoms joined by strong bonds.

Compound

Two or more atoms of different elements joined by strong or weak bonds.

Molecular weight

Sum of the atomic weights of its atoms.

Reactants

At the start of the reaction.

Products

Generated by the reaction.

Ion

Atom with an electric charge.

Cation

Atom that loses one or more electrons and becomes positively charged.

Anion

Atom that gains one or more electrons and becomes negatively charged.

Ionic bonds

Bonds formed by the attraction between cations and anions.

Covalent bonds

Strong bonds involving shared electrons.

Nonpolar covalent bonds

Equal sharing of electrons between atoms with equal pull.

Polar covalent bonds

Unequal sharing of electrons because one atom has a disproportionately strong pull.

Hydrogen bonds

Weak polar bonds between adjacent molecules based on electrical attractions.

Solid

Constant volume and shape.

Liquid

Constant volume but changes shape.

Gas

Changes volume and shape.

Reactants

Materials going into a reaction.

Products

Materials coming out of a reaction.

Metabolism

All of the reactions that are occurring at one time.

Energy

The capacity to do work.

Work

Movement of an object or change in matter.

Kinetic energy

Energy of motion.

Potential energy

Stored energy.

Chemical energy

Potential energy stored in chemical bonds.

Decomposition reaction (catabolism)

Breaks chemical bonds (AB → A + B).

Synthesis reaction (anabolism)

Forms chemical bonds (A + B → AB).

Exchange reaction

Involves decomposition first, then synthesis (AB + CD → AD + CB).

Reversible reactions

Reactions that seek equilibrium, balancing opposing reaction rates (A + B ↔ AB).

Activation energy

Amount of energy needed to start a reaction.

Enzymes

Protein catalysts that lower the activation energy of reactions.

Exergonic reactions

Release energy.

Endergonic reactions

Absorb energy.

Nutrients

Essential molecules obtained from food.

Metabolites

Molecules made or broken down in the body.

Inorganic compounds

Carbon dioxide, oxygen, water, and inorganic acids, bases, and salts.

Organic compounds

Molecules containing carbon and hydrogen (carbohydrates, proteins, lipids, nucleic acids).

Solutions

Uniform mixtures of two or more substances; consists of a solvent (liquid) and solutes (dissolved substances).

Solvent

The liquid part of a solution.

Solutes

The dissolved substances in a solution.

Heat capacity

heat required to raise the temperature of a unit mass of a substance 1ºC.

Ionization

Dissociation into ions.

Electrolytes

Inorganic ions that conduct electricity in solution.

Hydrophilic

Water loving; includes ions and polar molecules.

Hydrophobic

Water fearing; includes nonpolar molecules, fats, and oils.

Colloid

A solution containing dispersed proteins or other large molecules (e.g., blood plasma).

Suspension

Contains large particles that settle out of solution (e.g., whole blood).

pH

The negative logarithm of the hydrogen ion concentration of a solution in moles per liter.

Neutral pH

A balance of H+ and OH–; pure water = 7.0.

Acidic pH

Lower than 7.0; high H+ concentration, low OH– concentration.

Basic (or alkaline) pH

Higher than 7.0; low H+ concentration, high OH– concentration.

pH of human blood

Ranges from 7.35 to 7.45.

Acid

Solute that adds hydrogen ions to a solution (proton donor).

Base

Solute that removes hydrogen ions from a solution (proton acceptor).

Weak acids and weak bases

Fail to dissociate completely; help to balance the pH.

Salt

Solute that dissociates into cations and anions other than hydrogen ions and hydroxide ions.

Buffers

Stabilize pH of solutions; often involve a weak acid and its related salt (weak base).

Monomers and Polymers

Identical molecules join together to form a polymer.

Isomers

Molecules with the same molecular formula but different structures.

Monosaccharides

Simple sugars with three to seven carbon atoms (e.g., glucose, fructose, galactose).

Disaccharides

Two monosaccharides condensed by dehydration synthesis (e.g., sucrose, maltose).

Polysaccharides

Polymers of many sugars condensed by dehydration synthesis (e.g., glycogen, starch, cellulose).

Lipids

Mainly hydrophobic molecules such as fats, oils, and waxes; made mostly of carbon and hydrogen atoms.

Fatty acids

Long chains of carbon and hydrogen with a carboxyl group (COOH) at one end.

Saturated fatty acids

No double bonds in the hydrocarbon tail.

Unsaturated fatty acids

One or more double bonds in tail.

Eicosanoids

Derived from arachidonic acid; includes leukotrienes and prostaglandins.

Glycerides

Fatty acids attached to a glycerol molecule (monoglyceride, diglyceride, triglyceride).

Steroids

Four-ringed carbon structures with an assortment of functional groups (e.g., cholesterol, sex hormones, steroid hormones, bile salts).

Phospholipids and glycolipids

Contain a diglyceride attached to either a phosphate group (phospholipid) or a sugar (glycolipid); structural lipids—components of plasma membranes.

Proteins

Long chains of amino acids.

Primary structure

Sequence of Amino Acids Along a Polypeptide

Secondary structure

Hydrogen bonds form spirals or pleats

Tertiary structure

Coiling and folding produce three-dimensional shape

Quaternary structure

Final protein complex produced by interacting polypeptide chains.

Enzymes

proteins that lower the activation energy of a chemical reaction.

Cofactor

An ion or molecule that binds to an enzyme before substrates can bind.

Coenzymes

Nonprotein organic cofactors (vitamins).

Denaturation

Change in shape and loss of function due to heat or pH.

Glycoproteins

Large proteins + small carbohydrates (enzymes, antibodies, hormones, components of plasma membranes).

Proteoglycans

Large polysaccharides + polypeptides; increase viscosity of fluids.

Nucleic acids

Large organic molecules found in the nucleus; store and process information (DNA, RNA).

Deoxyribonucleic acid (DNA)

Determines inherited characteristics; directs protein synthesis; controls enzyme production; controls metabolism.

Ribonucleic acid (RNA)

Controls intermediate steps in protein synthesis.