Chapter 2 Flashcards
Define matter.
Anything that occupies space and has mass
Define mass.
The amount of matter in an object
Define weight.
The gravitational force acting on an object of a given mass.
Describe basic atomic structure and function.
Element - simplest type of matter having unique properties
Atom - smallest particle of an element that has chemical characteristics of that element. (neutrons, protons, electrons - no mass, most of the volume of an atom)
Nucleus - formed by protons and neurons (accounts for most of atom’s mass but very little of volume)
Describe an ionic bond.
A complete transfer of electrons between two atoms - results in separate positively charged and negatively charged ions.
What is an ion?
A charged atom: an atom that has lost or gained electrons
Cation - positive ion
Anion - negative ion
What is a covalent bond?
Formed when atoms share one or more pairs of electrons. Covalent bonds form molecules.
What is a single covalent bond?
The sharing of one pair of electrons by two atoms.
What is a double covalent bond?
When two atoms share 4 electrons, two from each atom.
What is a nonpolar covalent bond?
An equal sharing of electrons between two atoms - even charge distribution among atoms of the molecule.
What is a polar covalent bond?
An unequal sharing of electrons between two atoms - resulting in a slightly positive charge on one side of molecule and slightly negative charge on other side of molecule.
What is the difference between a molecule and a compound?
A compound is a type of molecule.
A molecule is formed when two or more atoms of an element chemically join together. If the types of atoms are different from each other, a compound is formed.
Not all molecules are compounds, since some molecules, such as hydrogen gas or ozone, consist only of one element or type of atom.
How do you find the molecular mass of a molecule?
Add up atomic masses of atoms involved
What is solubility?
The ability of one substance to dissolve in another.
Charged & polar substances readily dissolve.
Nonpolar substances do not readily dissolve.
SOLUTE DISSOLVES IN SOLVENT.
What is a hydrogen bond?
The attraction of oppositely charged ends of one polar molecule to another polar molecule - holds molecules or parts of molecules together.
Describe the solubility of an ionic compound.
When ionic compounds dissolve, their ions dissociate from one another becasue cations are attracted to negative ends of water molecules and anions are attracted to positive ends of water molecules.
What is the difference between reactants and products?
Reactants - substances that enter chemical reaction
Products - substances that result from chemical reaction
What is a synthesis reaction?
When two ore more reactants chemically combine to form a new and larger product.
ANABOLISM! (all synthesis reactions)
Dehydration reaction is when water is produced (water comes OUT of the reaction)
What is a decomposition reaction?
When a larger reactant is chemically broken down into two or more smaller products.
CATABOLISM! (all decomposition reactions)
Hydrolysis reaction occurs if water split into two parts and each part contributes to each new molecule.
What is metabolism?
All of the anabolic and catabolic reactions in the body.
What is a redox reaction?
An oxidation-reduction reaction.
Chemical reactions that result from the exchange of electrons between the reactants.
Na+ - Cl-
Complete transfer? Ionic bond
Partial transfer? Covalent bond
What is oxidation?
Loss of an electron
What is reduction?
Gain of an electron.
What three things affect the speed of a chemical reaction?
Temperature
Concentration of reactants - as concentration increases, rate of reaction increases
Catalysts
Define a catalyst.
A substance that increases the rate of a reaction without being permanently changed or depleted itself.
What is an enzyme?
Proteins that act as catalysts. Enzymes increase the rate of chemical reactions by lowering the amount of activation energy needed for the reaction to begin. Allows the rate of a chemical reaction to take place more than a million x faster.
Describe metabolism in terms of catabolism and anabolism.
Metabolism is the set of chemical reactions that happen in living organisms that sustain life.
Bodies need to obtain energy through proteins, fats, carbs and nucleic acids. The food we eat may not contain these variables specifically, so we break down (catabolism: cutting) the food into what our bodies need (amino acids, fatty acids, glucose or nucleotides) then rebuild these components (anabolism) to create the energy our cells need to sustain life - ATP.
What is cohesion?
Attraction of water to another water molecule.
Example: surface tension when water bulges over top of full glass without spilling.
What is adhesion?
Attractive force of hydrogen bonds with water will also attract other molecules.
What is the composition of water in the body?
Plasma (liquid portion of blood) is 92% water
Water weight of body is 50-60%. (female - male)
What are the functions of water in the body?
Stabilizing body temperature
Protection (lubricant/cushion)
Chemical reactions (dehydration/hydrolysis)
Mixing medium
What is a mixture?
Combination of two or more substances physically blended together.
NOT CHEMICALLY COMBINED.
What is a suspension mixture?
Mixture containing materials that separate from each other unless they are continually, physically blended.
SAND IN WATER
What is a colloid mixture?
Mixture in which substances are distributed throughout a dispersing substance (mix).
MILK
What is a solution?
Any mixture of liquids, gases or solids in which the substances are uniformly distributed with no clear boundary between them.
TOMATO SOUP OR IV BAG
What sort of mixture/solution is blood?
Blood is a mixture (red/white cells can settle), a solution (mix of water, cells, etc) and a colloid (plasmas have proteins mixed in).
What is an acid?
A proton donor.
What is a base?
A proton acceptor and any substance that binds to (accepts) H+.
What is a neutral solution?
A solution with equal concentrations of H+ and OH-.
Pure water is a solution with a pH of 7.
What is an acidic solution?
A solution with a pH that is LESS THAN 7.
Has greater concentration of…
H+ > OH-
What is a basic solution?
A basic (alkaline) solution has a pH GREATER THAN 7.
Has greater concentration of…
H+ < OH-
What is the normal pH range for human blood?
7.35 - 7.45
What results if a blood’s pH drops below 7.35?
Acidosis
What results of a blood’s pH rises above 7.45?
Alkalosis
What is a salt?
A compound consisting of a cation other than H+ and an anion other than OH-.
Formed by the interaction of an acid and base in which the H+ of acid are replaced by positive ions of the base.
NaCl
What is a buffer?
Chemicals that resist changes in pH when either acids or bases are added to a solution.
IMPORTANT BUFFERS
Bicarbonate
Phosphates
Amino acids
Proteins
What is oxygen?
An inorganic molecule consisting of two oxygen atoms bound together by a double covalent bond.
Required in final step of a series of reactions that extract energy from food molecules.
What is carbon dioxide?
One carbon atom bound to two oxygen atoms. Each oxygen atom is bound to the carbon atom by a double covalent bond.
Produced when organic molecules, like glucose, are metabolized within the cells.
How does carbon dioxide interact with plasma?
CO2 combines with the water in plasma, forming H+ as a byproduct and affecting the acid/base balance.
What are the four major organic compounds essential to living organisms?
Carbohydrates
Lipids
Proteins
Nucleic acids
What are carbohydrates?
Primarily consist of C, H and O atoms.
Range from small to very large
Major energy source
What are lipids?
FATS!
Composed of C, H and O atoms.
Relatively insoluble in H2O.
What are the functions of lipids?
Protection Insulation Physiological regulation Component of cell membranes Energy source
What are proteins and what is their function?
Composed of C, H, O, N and sometimes I.
Functions: Regulate processes Aid transport Protection Muscle contraction Structure Energy
What are nucleic acids?
Composed of C, H, O, N and P.
Examples: ATP, DNA, RNA
Creates gene structure & transfer of genes.
