Chapter 2 Flashcards
anything that occupies space and has mass.
Matter
the amount of matter in an object.
Mass
International unit for mass
kilogram (kg)
the gravitational force acting on an object of a given mass
Weight
composed of subatomic particles.
Atoms
no electrical charge
Neutrons
one positive charge.
Protons
one negative charge.
Electrons
formed by protons and neutrons.
Nucleus
Most of the volume of an atom occupied by electrons. Represented as an?
electron cloud.
If the valence shell is incomplete, the atom is chemically reactive and forms chemical bonds to achieve an octet called what rule
Octet rule
two or more forms of same element with same number of protons and electrons but different neutron number. They have the same atomic number but different mass numbers.
Isotopes
average mass of naturally occurring isotopes.
Atomic Mass
The unified atomic mass unit is 1/12 of the mass of 12C; called the?
Dalton (Da)
equal to number of protons in each atom, which is equal to the number of electrons.
Atomic Number
number of protons plus number of neutrons.
Mass Number
are formed when electrons in the outermost energy level (valence shell) are either shared with or transferred to another atom.
Chemical bonds
electrons are transferred from one atom to another.
lonic Bonding
two or more atoms share electron pairs.
Covalent Bonding
solutions made by the dissociation of cations (+) and anions (-) in water.
• Have the capacity to conduct an electric current.
• Currents can be detected by electrodes.
Electrolytes
solutions made by molecules that dissolve in water, but do not dissociate; do not conduct electricity.
Nonelectrolytes
Atoms, ions, molecules or compounds interact to form or break chemical bonds.
Chemical reaction
substances that enter into a chemical reaction
Reactants
substances that result from the reaction
Products
(synthesis-)?
anabolism
(decomposition;)? during chemical reactions.
catabolism
collective term used for the sum of all of the anabolic and catabolic reactions in the body
Metabolism
Two or more reactants chemically combine to form a new and larger product. Collective term for synthesis reactions in body is?
anabolism
synthetic reaction where water is a product.
Dehydration reaction
A large reactant is broken down to form smaller products. Collective term for decomposition reactions in body is?
catabolism
water is split into two parts that contribute to the formation of the productions
Hydrolysis reactions
rate of product formation is equal to rate of reactant formation.
Equilibrium
loss of an electron by an atom
Oxidation
gain of an electron by an atom
Reduction
the complete or partial loss of an electron oby one atom is accompanied by the gain of that electron by another atom.
Oxidation-reduction reactions
is the capacity to do work (for example, to move matter).
Energy
energy stored in chemical bonds; energy that could do work if it were released. Breaking chemical bonds releases energy.
Potential energy
does work and moves matter.
Kinetic energy
principal states that the total amount of energy in the universe is constant. Energy is neither created nor destroyed, it only changes form.
Conservation of energy
energy resulting from the position or movement of objects.
Mechanical energy
energy resulting from the position or movement of objects.
Mechanical energy
form of potential energy in the chemical bonds of a substance.
Chemical energy
energy that flows between objects of different temperatures.
Heat energy
A form of energy that flows from a hotter object to a cooler object.
Heat Energy
minimum energy reactants must have to start a chemical reaction.
Activation Energy
substances that increase the rate of chemical reactions without being permanently changed or depleted.
Catalysts
protein catalysts that increase the rate of chemical reactions by lowering the activation energy necessary for reaction to begin
Enzymes
• Increase in ___ means increase of kinetic energy.
• Molecules move faster, collide harder and more frequently.
Temperature
increases, rate of reaction increases
• Example: A decrease of O2 in cells can cause death as rate of aerobic chemical reactions decreases.
Concentration of reactants
substances that do not contain carbon-hydrogen obonds.
• Water, oxygen, carbon dioxide, calcium
• phosphate, metal ions.
Inorganic Chemistry
study of carbon-containing substances.
Organic Chemistry
substances attracted to water; “water-loving”.
Hydrophilic
substances not attracted to water; “water-fearing”.
Hydrophobic
is the attraction of one water molecule to another; creates a surface tension
Cohesion
is the attraction of water molecules to other molecules; causes the upward movement of water in the xylem of plants.
Adhesion
allows transport throughout the body.
Mixing medium
substances physically but not chemically combined.
Mixture
mixture of liquids, gasses, or solids that are uniformly distributed.
Solution
that which dissolves the solute.
Solvent
materials separate unless stirred.
Ex: Sand and water; blood cells in plasma
Suspension
dispersal of tiny particles through a medium that do not settle out.
• Milk, plasma of the blood, cell interior
Colloid
measure of number of particles of solute per volume of solution.
Concentration
reflects the number of particles dissolved in one kilogram of water.
Osmolality
One osmole (Osm) is equal to ___ of particles in one kilogram of water?
Avogadro’s number
Unit used by physiologists is ___ because of the low concentrations in the human body?
milliosmoles (mOsm)
mOsm is average in the human body?
300
a proton acceptor or any substance that binds to or accepts hydrogen ions.
Base
a proton donor or any substance that releases hydrogen ions.
HCI → H+ + CI
Acid
Refers to the hydrogen ion concentration in a solution
The pH Scale
pH of 7 or equal amounts of hydrogen and hydroxide ions.
Neutral
pH of less than 7 with a greater concentration of hydrogen ions.
Acidic
pH of greater than 7 and a greater concentration of hydroxide ions.
Alkaline (basic)
The normal pH range for human blood is?
7.35 to 7.45
blood pH drops below 7.35, a condition called?
acidosis
If blood pH rises about 7.45, a condition called?
alkalosis
a compound consisting of a cation other than a hydrogen ion and an anion other than a hydroxide ion.
Example: NaCl
Salt
a solution of a conjugate acid-base pair in which acid and base components occur in similar concentrations; this combination resists changes in pH when either acids or bases are added to the solution.
Buffer
required in the final step in the series of reactions used to extract energy from food.
Oxygen (O2)
produced during the catabolism of organic compounds.
• Metabolic waste product.
• Combines with water in plasma and forms H+ thus affecting acid-base balance.
Carbon dioxide (CO2)
bound together by covalent bonds constitute the backbone of many large biomolecules by varying the length of the carbon chains and the combination of atoms involved.
Carbon atoms
composed of carbon, hydrogen, oxygen.
• Divided into monosaccharides, disaccharides, polysaccharides.
• Energy sources, structure, and bulk for elimination.
• Water soluble
Carbohydrates
composed mostly of carbon, hydrogen, oxygen.
• Relatively insoluble in water.
• Functions: protection, insulation, physiological regulation, component of cell membranes, energy storage.
Lipids
composed of carbon, hydrogen, oxygen, nitrogen, sometimes sulfur.
• Functions: regulate processes, aid transport, protection, muscle contraction, structure, energy.
Proteins
composed of carbon, hydrogen, oxygen, nitrogen, phosphorus.
• Examples: ATP, DNA, RNA.
Nucleic Acids
One fatty acid replaced with a phosphate group; polar (hydrophilic) at one end; nonpolar (hydrophobic) at the other.
Lipids: Phospholipids
composed of glycerol and fatty acids.
• Each fatty acid has a carboxyl group.
• Fatty acids combine with glycerol to form triglyceride.
Triglycerides
building blocks of protein.
Amino acids
covalent bonds formed between amino acids during protein synthesis by dehydration.
Peptide bonds
the amino acid sequence
Primary structure
results from hydrogen bonding between amino acids.
• Pleated (folded) sheets.
• Helices.
Secondary structure
change in shape caused by breaking of H-bonds by heat or pH changes.
Denaturation
large-scale folding due to interactions within protein and surrounding environment which is generally water.
Tertiary structure
Three-dimensional shape contains an ___ where reactants attach?
active site
reaction occurs when reactants bind to active site
Lock-and-key model
enzymes change shape to accommodate the shape of specific reactants.
Induced fit model
nonprotein substances that combine with active site and make nonfunctional enzymes functional.
Cofactors
Genetic material of cells copied from one generation to next.
Composed of 2 strands of DNA nucleotides.
DNA
sequence of bases that codes for synthesis of RNA or protein.
Gene
Adenosine Triphosphate (ATP)
~Energy currency of the body because it both stores energy and provides energy.
~Provides energy for other chemical reactions as anabolism or drive cell processes as muscle contraction.
~All energy-requiring chemical reactions stop when there is inadequate
