A and P Chapter 2 Flashcards
What six natural elements account for 98.5% of our body weight?
oxygen, carbon, hydrogen nitrogen, calcium, phosphorous
What 6 elements make up .8% ?
sulfur, potassium, sodium, chlorine, magnesium, iron
Trace elements
elements that do not account for more than .2% of body weight
Minerals
inorganic elements that are extracted from the soil by plants and passed up the food chain to humans and other organisms
Protons
a single positive charge
Neutrons
no charge
Electrons
tiny particles with a single negative charge and very low mass, determine chemical properties of an atom
Valence Electrons
electrons of the outermost shell
Isotopes
elements with varying neutrons and atomic mass
Hydrogen with one nuetron
Deuterium
Radioisotopes
unstable isotopes
Radioactivity
decay
Ionizing Radiation
ejecting electrons from atoms, converting them to ions
Three Kinds of Ionizing Radiation
Alpha, Beta particles, and Gamma rays
Physical half life
time required for 50% of radioisotope atoms to decay to a more stable state
Biological half life
time required for half of a radioisotope to disappear from the body
Radon
gas produced by the decay of uranium in the Earth
Ions
charged particles with unequal number of protons and electrons
Anion
Particle gains electrons and becomes negative
Cation
Particle loses an electron and becomes positive
Electrolytes
substances that ionize in water and form solutions capable of conducting solutons
Free Radicals
chemical particles with an odd number of electrons
Antioxidant
chemical that neutralizes free radicals
Molecules
chemical particles composed of two or more atoms united by a chemical bond
Compounds
molecules composed of two or more elements
Isomers
molecules with identical molecular formulas but different arrangements of their atoms
Molecular Weight
sum of the atomic mass of its atoms
Ionic Bond
attraction of a cation to an anion
Covalent Bonds
sharing of electrons
Hydrogen Bonds
weak attraction between a slightly positive hydrogen and slightly negative oxygen or nitrogen
Van der Waals
weak brief attractions between neural atoms
Mixture
substances that are physically blended but not chemically combined
Water
Atoms joined by covalent bonds and molecules are v-shaped
Solvency
ability to dissolve other chemicals
Hydrophilic
substances that dissolve in water
Hydrophobic
substances that do not dissolve in water
Adhesion
tendency of one substance to cling to another
Cohesion
tendency of molecules of the same substance to cling to each other
Surface Film
cohesion of water at surface, forming an elastic layer
Surface Tension
force holding surface film together
Chemical Reactivity
ability to participate in chemical reactions
Thermal Stability
help stabilize internal temp of body
Base unit of heat
Calorie (cal)
Solution
consists of particles of matter, solute, mixed with solvent
Colloids
mixtures of protein and water, albumin in blood plasma
Suspension
particle suspension in solute
Emulsion
suspension of one liquid in another
Molarity
number of moles of solute per liter of solution
Acid
proton donor
Base
proton acceptor
pH
measure derived from the molarity of hydrogen
Bloods normal pH range?
7.35-7.45
Buffers
chemical solutions that resist changes in pH
Potential Energy
energy contained in an object because of its position or internal state
Kinetic Energy
energy of motion, doing work
Chemical Energy
potential energy stored in bonds of molecules
Heat
kinetic energy of molecular motion
Electromagnetic Energy
kinetic energy of moving “packets” of radiation, photons
Chemical Reaction
process in which a covalent or ionic bond is formed or broken
Chemical Equation
symbolizes the course of a chemical reaction
reactants–>products
Decomposition Reactions
large molecule breaks down into two or more smaller ones
Synthesis Reactions
two or more molecules combine to form a larger one
Exchange Reactions
two molecules exchange atoms or group of atoms
Reversible Reactions
reaction that can go in either reaction under different circumstances
Law of Mass Action
atoms proceed from reactants with greater quantity to the substances with the lesser quantity
Concentration- Reaction Rates
reaction rates increase when the reactants are more concentrated
Temperature- Reaction Rates
reaction rate increases as temperature rises
Catalysts
substances that temporarily bind to reactants
Metabolism
all the chemical reactions in the body
Catabolism
energy-releasing decomposition reactions
Anabolism
energy storing synthesis reactions
Oxidation
any chemical reaction in which a molecule gives up electrons and releases energy
Reduction
chemical reaction in which a molecule gains electrons and energy
Dehydration Synthesis
condensation, a hydroxyl group is removed and a hydrogen from another, creating water as a byproduct
Hydrolysis
a water molecule ionizes creating a bond
Carbohydrate
a hydrophilic organic molecule with a 2:1 ratio of hydrogen to oxygen
Monosaccharides
simple sugars, glucose, fructose, and galactose
Disaccharides
sugars composed of two monosaccharides, sucrose, lactose, and maltose
Oligosaccharides
three or more monosaccharides
Polysaccharides
long chains of monosaccharides
Glycogen
energy-storage polysaccharide made by the body
Starch
energy-storage polysaccharide of plants
Cellulose
structural polysaccharide that gives strength to cells walls of plants
Lipid
hydrophobic organic molecule, usually composed of carbon, hydrogen, and oxygen, high ratio of hydrogen to oxygen
Fatty Acid
a chain of 4 to 24 carbon atoms with a carboxyl group at one end and a methyl group at the other end
Phospholipids
similar to neutral fats but instead of a fatty acid, they have a phosphate group
Steroid
lipid with 17 of its carbon atoms arranged in four rings
Cholesterol
parent steroid from which others are synthesized
Protein
a polymer of amino acids
Peptide
any molecule composed of two or more amino acids joined by peptide bonds
Peptide Bonds
joining of amino acids by dehydration synthesis
Primary Protein Structure
proteins sequence of amino acids
Secondary Protein Structure
coiled or folded shape held together by by hydrogen bonds, alpha helix or beta sheet
Denaturation
conformational change due to conditions such as extreme heat or pH
Protein Functions
structure, communication, membrane transport, catalysis, recognition and protection, movement, cell adhesion
Enzymes
proteins that function as biological catalysts
Substrate
the substance an enzyme acts upon
Activation Energy
energy needed to get a reaction started
Cofactor
non-protein partner for human enzmes
Coenzymes
organic cofactors usually derived from niacin, riboflavin, and water-soluble vitamins
Metabolic Pathway
chain of reactions with each step usually catalyzed by a different enzyme
Nucleotides
organic compounds with three principal components: single or double- carbon-nitrogen ring, monosaccharide, and one or more phosphate groups
ATP
adenosine triphosphate, body’s most important energy transfer molecule
ATPases
adenosine triphosphatases, hydrolyze third phosphate bond
ADP
adenosine diphosphate
Phosphorylation
addition of an inorganic phosphate group
Kinases
carry out phosphorylation
Glycolysis
“sugar splitting” makes 2 ATP molecules, split six carbon glucose to two three carbon molecules of pyruvic acid
Anaerobic Fermentation
pathway to convert excess pyruvic acid into lactic acid
Aerobic Respiration
Breaking pyruvic acid to carbon dioxide and water when oxygen is present, 36 ATP molecules made for each glucose
GTP
guanosine triphosphate, in some reactions, donates phosphate groups to other molecules, nucleotide
cAMP
cyclic adenosine triphosphate, nucleotide formed by removal of both second and third phosphate groups from ATP
Nucleic Acids
polymers of nucleotides, DNA and RNA
