BiSci Ch. 2 Flashcards
Matter
refers to anything that takes up space and has mass. can exist as a solid, liquid, or a gas.
Element
one of the basic building blocks of matter; it cannot be broken down by chemical means.
Atom
is the smallest unit of an element still remains the chemical and physical properties of the element.
Proton
positively charged
Neutron
uncharged
Electron
negatively charged
Electron Shell
the circle around the nucleus, where the average location of electrons
Atomic Number
number of protons within the nucleus of the atom.
Mass Number
is the sum of protons and neutrons in the nucleus.
Atomic Mass
the number below the atomic symbol on the periodic table. is the average of the AMU for all the isotopes of that atom.
Isotopes
of the same number of protons but different number of neutrons.
Molecule
atoms often bond with one another to form a chemical unit.
Compound
substance having two or more different elements united chemically in a fixed ratio.
Ions
are particles that carry either a positive or negative charge.
Covalent Bonds
atoms share electrons thru this.
Polar
Combination of atoms in which the electrical charge is not distributed symmetrically.
Hydrogen Bond
weak bond that arises between a slightly positive hydrogen atom of one molecule and a slightly negative atom of another, or between parts of the same molecule.
Calorie
is the amount of heat energy of food.
A Solution
contains dissolved substances, which are then called solutes.
Hydrophobic
type of molecule that does not interact with water bc it is non polar.
Bases
are substances that either take up hydrogen ions or release hydrogen ions.
pH Scale
is used to indicate the acidity or basicity of a solution.
Buffer
substance or group of substances that tend to resist pH changes of a solution, thus stabilizing its relative acidity or basicity.
Organic Molecule
type of molecule that contains canon and hydrogen- and often contains oxygen also.
Macromolecule
a molecule that contains many subunits, it uses dehydration reaction, a type of synthesis reaction.
Hydrolysis Reaction
the components of water are added during the breaking of the bond between molecules.
Carbohydrate
class of organic compounds that includes monosaccharides, disaccharides, and polysaccharides.
Monosaccharide
simple sugar; a carb that cannot be decomposed by hydrolysis.
Glucose
six-carbon sugar that organisms degrade as a source of energy during cellular respiration.
Disaccharide
is made by joining only two monosaccharides together by dehydration reaction.
Polysaccharide
polymer made from sugar monomers; the starch and glycogen are polymers glucose monomers.
Starch
storgage polysaccharide found in plants; composed of glucose molecules joined in a linear fashion with few side chains
Glycogen
storage polysaccharide composed of glucose molecules joined in a linear fashion but having numerous branches.
Cellulose
also known as fiber; polysaccharide that is the major complex carb in plant cell walls.
Lipids
class of organic compounds that tends to be soluble only in non polar solvents such as alcohol; includes fats and oils. (not soluble in water)
Oils
substance, usually of a plant origin and liquid at room temp, formed when a glycerol molecule reacts with three fatty acid molecules.
Emulsification
breaking up of fat globules into smaller droplets by the action of bile salts or any other emulsifier.
Triglyceride
neutral fat composed of glycerol and three fatty acids.
Fatty Acid
molecule that contains a hydrocarbon chain and ends with an acid group.
Saturated Fatty Acids
fatty acid molecule that lacks double bonds between the atoms of its carbon chain.
Unsaturated Fatty Acid
fatty acid molecule that has one or more double bonds between the atoms of its carbon chain.
Trans Fats
fats, which occur naturally in meat and dairy products of ruminants, that are also industrially created thru partial hydrogen of plant oils and animal fats
Phosholipid
lipid molecule that forms the bilayer of the cell`s membranes; has a polar, hydrophilic to two non polar, hydrophobic tails.
Steroid
type of lipid molecule having a complex of four carbon rings; examples are cholesterol, progesterone, and testosterone.
Protein
molecule consisting of two or more polypeptides.
Amino Acid
organic molecule having an amino group and an acid group, which covalently bonds to produce peptide molecules.
Peptide Bond
the covalent bond between two amino acids
Polypeptide
when three or more amino acids are linked by peptide bonds
Denaturation
loss of normal shape by enzyme so that it no longer functions; caused by less than optimal pH or temp.
Primary Structure
the first level of protein organization. is the linear sequence of the amino acids joined by peptide bonds.
Secondary Structure
the second level of protein organization. a protein comes about when the polypeptide takes on a certain orientation in space.
Tertiary Structure
of a protein, is its final three dimensional shape.
Quaternary Structure
fourth level of protein structure.
Nucleic Acids
are polymers of nucleotides, store info, include instructions for life, and conduct chemical reactions.
DNA (deoxyribonucleic acid)
nucleic acid polymer produced from covalent boning of nucleotide monomers that contain the sugar deoxyribose; the genetic material of nearly all organisms.
RNA (ribonucleic acid)
nucleic acid produced from covalent bonding of nucleotide monomers that contain the sugar ribose; occurs in three major forms
ATP (adenosine triphosphate)
nucleotide with three phosphate groups. the breakdown of this into ADP+P makes energy available for energy-requiring processes in cells.
Coenzymes
nonprotein organic molecules that help regulate enzymatic reactions.
Nucleotide
monomer of DNA and RNA consisting of a 5-carbon sugar bounded to a nitrogen-containing base and phosphate group.
Adenine (A), Thymine (T), Guanine (G), Cytosine, Uracil (U)
the nitrogen bases in nucleotides composing the structure of DNA and RNA.
Strand
the nucleotides line to make a polynucleotide, which is the backbone make up of phosphate-sugar-phosphate-sugar.
Complementary Base Pairing
hydrogen bonding between particular bases; in DNA (T pairs with A, and G pairs with C) in RNA (U pairs with A, and G pairs with C).
ADP (adenosine diphosphate)
nucleotide with two phosphate groups that can accept another phosphate group to become ATP.
