Exam 1

Molecule

A particle composed of two or more atoms united by a chemical bond.

Compound

A molecule composed of two or more different elements.

Trace Elements

Elements present in minute amounts in the body but play vital roles.

Covalent Bond

A bond formed when atoms share one or more pairs of electrons.

Ionic Bond

An attraction between cations and anions.

Hydrogen Bond

A weak attraction between a slightly positive hydrogen atom and a slightly negative atom.

Solution

A mixture where a solute is dissolved in a solvent.

Suspension

A mixture in which particles exceed 100 nm and separate on standing.

Emulsion

A suspension of one liquid in another.

Colloid

A mixture where particles range from 1 to 100 nm and remain evenly distributed.

Anabolic Reactions

Energy-storing synthesis reactions that create larger molecules from smaller ones.

Catabolic Reactions

Energy-releasing decomposition reactions that break larger molecules into smaller ones.

Amino Acid

Organic compounds that serve as the building blocks of proteins.

Most Abundant Elements in the Body

Oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus.

Atomic Number

The number of protons in the nucleus of an atom.

Atomic Mass

The mass of an atom, usually approximately equal to the total number of protons and neutrons.

Determining Chemical Properties

Valence electrons determine the chemical properties and bonding capabilities of an atom.

Salt Dissolving in Water

When salt is put in water, it dissociates into its ions.

Anion

A negatively charged ion.

Cation

A positively charged ion.

Properties of Water

Solvency, cohesion, adhesion, chemical reactivity, and thermal stability.

Molecules per Volume

The number of molecules in a given volume of solution.

pH Scale

A scale that measures the acidity or basicity of a solution.

Blood pH Regulation

The body maintains constant blood pH through buffer systems.

Types of Chemical Reactions

Decomposition, synthesis, exchange, and reversible reactions.

Exergonic Reaction

A reaction that releases energy.

Endergonic Reaction

A reaction that requires energy input.

Factors Affecting Reaction Rate

Concentration of reactants, temperature, and presence of catalysts.

Functional Groups

Specific groups of atoms within molecules that determine the characteristics of those molecules.

Organic Compound Criteria

A compound is considered organic if it contains carbon.

Hydrolysis

The process of breaking down a polymer by adding water.

Dehydration Synthesis

The process of joining two monomers to form a polymer, releasing water.

Elements in Macromolecules

Carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.

Examples of Macromolecules

Carbohydrates, proteins, nucleic acids, and lipids.

Structure of Macromolecules

Organized in specific, complex formations to perform biological functions.

Hydrophobic

Substances that do not interact well with water.

Hydrophilic

Substances that dissolve well in water.

Functions of Macromolecules

Energy storage, structural support, catalyzing reactions, etc.

Denaturation

A structural change in proteins causing loss of function.

Levels of Protein Structure

Primary, secondary, tertiary, and quaternary structures.

DNA

Deoxyribonucleic acid, a molecule that contains genetic instructions.

RNA

Ribonucleic acid, involved in protein synthesis.

Reactants in a Reaction

Substances that undergo a chemical change in a reaction.

Products of a Reaction

Substances formed as a result of a chemical reaction.

Carbon Versatility

Carbon can form a variety of structures due to its four valence electrons.

Minerals Function in the Body

Essential for diverse physiological processes, including enzyme function.

Buffer System Function

Resist changes in pH to maintain homeostasis.

Examples of Buffer Systems

Bicarbonate, phosphate, and protein buffer systems.

Bicarbonate Buffer Reaction

$H_2CO_3 \rightleftharpoons HCO_3^- + H^+$.

Buffer in Blood

Bicarbonate acts as a buffer to maintain blood pH.

Kidneys and pH Regulation

Help maintain pH balance by excreting or retaining hydrogen ions.

Metabolic Alkalosis

A condition characterized by increased pH due to loss of hydrogen ions.

Metabolic Acidosis

A condition characterized by decreased pH due to excess hydrogen ions.

Urinary Alkalosis

Increased pH in urine due to decreased hydrogen ion excretion.

Urinary Acidosis

Decreased pH in urine due to excess hydrogen ion excretion.

Respiratory Acidosis

A condition characterized by increased carbon dioxide concentration.

Diabetic Acidosis

A condition resulting from increased ketone bodies in the blood.

Biochemistry

The study of molecules that compose living organisms.

Major Macromolecule Groups

Carbohydrates, fats, proteins, and nucleic acids.

Cellular Functions of Biochemistry

Understanding cellular structures and physiological functions.

Body Elements Identified by Symbols

Elements in the body can be identified by their chemical symbols.

Elements vs Compounds Definition

Elements are pure substances, compounds are combinations of different elements.

Function of Minerals

Minerals have various roles, including structural and functional roles.

Radioactivity Basis

Radioactivity arises from unstable isotopes that decay and emit radiation.

Ions Definition

Charged particles formed when atoms lose or gain electrons.

Electrolytes Definition

Ionic substances that dissociate in water and conduct electricity.

Free Radicals Definition

Unstable and highly reactive particles with an unbalanced number of electrons.

Chemical Bonds Definition

Forces that hold atoms together in molecules.

Atomic Structure Components

Nucleus (protons and neutrons) and electron clouds.

Protons Definition

Positively charged particles found in the nucleus of an atom.

Neutrons Definition

Neutral particles found in the nucleus of an atom.

Electrons Definition

Negatively charged particles that orbit the nucleus.

Isotopes Definition

Varieties of an element that differ in neutron number.

Radioisotopes Definition

Unstable isotopes that decay and emit radiation.

Half-Life Definition

The time required for half of a sample of a radioactive substance to decay.

Biological Half-Life Definition

The time required for half of a substance to be eliminated from the body.

Sievert (Sv) Definition

Standard unit of measurement for radiation dosage.

Sources of Radiation

Natural and artificial sources of radiation exposure.

Natural Background Radiation Sources

Radon gas and cosmic rays that contribute to background radiation.

Artificial Radiation Sources

Human-made sources like X-rays and color TVs.

Madame Curie Contribution

Discovered radioactivity and trained physicians in radiation therapy.

Ion Definition

Charged atom or molecule formed by the loss or gain of electrons.

Anion vs Cation

Anion is a negatively charged ion; cation is a positively charged ion.

Ionic Bonds Definition

Forces of attraction between ions of opposite charge.

Salt Example

Sodium chloride (NaCl) is a common ionic compound.

Electrolytes Functions

Conduct electric current, essential for nerve and muscle function.

Cohesion

Attraction between molecules of the same substance.

Adhesion

Attraction between molecules of different substances.

Solvency of Water

Water's ability to dissolve various solutes.

Hydrophobic vs Hydrophilic

Hydrophobic substances do not interact with water; hydrophilic substances do.

Chemical Reactivity of Water

Water participates in many chemical reactions.

Thermal Stability of Water

Water's high heat capacity allows it to stabilize temperature.

Hydration Spheres

Spheres formed around ions when they dissolve in water.

Dissociation of Salt

Salts dissociate into anions and cations in solution.

Concentration Measurement Types

Weight per volume, percentage, molarity, and body fluid units.

Hydrolysis Reaction Example

Breaking down complex molecules by adding water.

Dehydration Synthesis Example

Combining two monomers while releasing water.

Acids Definition

Substances that release H+ ions in solution.

Bases Definition

Substances that accept H+ ions or release OH- ions.

pH Neutral Definition

pH of 7, indicating equal concentrations of H+ and OH-.