exam 1 Flashcards
1
Q
organic compound
A
any compound containing carbon
2
Q
macromolecules
A
huge molecules
ex: carbs, proteins, nucleic acids
3
Q
valence
A
the number of unpaired electrons in the outer shell of an atom
4
Q
hydrocarbons
A
organic molecules consisting of only carbon and hydrogen
5
Q
functional groups
A
the chemical groups tat affect molecular function by being directly involved in chemical reactions
6
Q
adenosine triphosphate
A
ATP, important organic compound for storing energy
7
Q
polymer
A
long molecule consisting of many similar or identical building blocks linked by covalent bonds
8
Q
monomer
A
the repeating units that are the building blocks of a polymer
9
Q
enzymes
A
specialized macromolecules (usually proteins) that speed up chemical reactions
10
Q
dehydration reaction
A
when water is taken away frorm two molecules and creates a bond, energy is absorbed
11
Q
hydrolysis
A
water is added, bonds broken, energy released
12
Q
carbohydrates
A
include both sugars and polymers of sugars
13
Q
monosaccharides
A
most simple sugars
have molecular formulas that are some multiple of the unit CH2O
14
Q
cellular respiration
A
cells extract energy from glucose in a series of reactions that break down its molecules
15
Q
disacchiride
A
two monosaccharides
16
Q
glycosidic linkage
A
covalent bond formed between two monosacharides in a dehydration reaction
17
Q
polysaccharides
A
macromolecules
polymers with a few hundred to few thousand monosaccharides joined by glycosidic linkage
18
Q
starch
A
plant storage of polysaccharide, polymer of glucose monomers
19
Q
glycogen
A
animal storage of polysaccharide, polymer of glucose monomers
20
Q
cellulose
A
major component of the tough walls that enclose plant cells
most organic compound on earth
21
Q
chitin
A
the carbohydrate used by arthropods (insects, spiders, crustaceans, and related animals) to build their exoskeletons
22
Q
lipids
A
generally not big enough to be considered macromolecules
they mix poorly with water
polymer of fatty acid
23
Q
fat
A
constructed from two kinds of smaller molecules: glycerol and fatty acids
24
Q
glycerol
A
alcohol
each of its three carbons bears a hydroxyl group
25
fatty acids
long carbon skeleton, carbon at one end of the skeleton is pat of a carboxyl group, the functional group that gives these molecules the name fatty acid
the rest of the skeleton consists of a hydrocarbon chain
26
triacylglycerol
three fatty acid molecules joined to glycerol by an ester linkage
27
ester linkage
a bond between hydroxyl group and a carboxyl group
28
saturated fatty acid
if there are no double bonds between carbon atoms composing a chain, then as many hydrogen atoms as possible are bonded to the carbon skeleton
29
unsaturated fatty acid
has one or more double bonds
| with one fewer hydrogen atom on each double bonded carbon
30
phospholipid
major constituents for cell membranes
| similar to a fat molecule but only has two fatty acides attached to glycerol rather than 3
31
steroids
lipids are characterize by a carbon skeleton consisting of four confused rings
32
cholestorol
crucial steroid in animals
common component of animal cell memberanes and is also the precursor from which other steroids are synthesized
such as the vertebrate sex hormones estrogen and testosterone
33
catalysts
chemical agents that selectively speed up chemical reactions without being consumed by the reaction
34
polypeptides
proteins are made up of polymers of amino acids called this
35
protein
biologically functional molecule that consists of one or more polypeptides folded and coiled into a specific three dimension structure
36
amino acid
organic molecule with both an amino group and a carboxyl group
37
peptide bond
when two amino acids are positioned so that the carboxyl group of one is adjacent to the amino group of the other, they can become joined by a dehydration reaction, with the removal of a water molecule
the resulting covalent bond is a peptide bond
38
primary structure of a protein
is its sequence of amino acids
39
secondary structure
Most proteins have segments of their polypeptide chains repeatedly coiled or folded in patterns that contribute to the protein's overall shape. these coils and folds are collectively referred to the secondary structure
40
a helix
type of secondary structure
| a delicate could held together by hydrogen bonds between the repeating constituents of the polyeptide backbone
41
B pleated sheet
other type of secondary structure
in this structure two or more segments of the polypeptide chain lying side by side are connected by hydrogen bonds between parts of the two parallel segments of polypeptide backbone
42
tertiary structure
overall shape of a polypeptide resulting from interactions from between the side chains (R groups) of various amino acids
43
hydrophobic interaction
as polypeptide folds into its functional shape, amino acids with hydrophobic (nonpolar) side chains usually end up in clusters at the core of the protein, out of contact with water
caused by exclusion of nonpolar substances by water molecules
44
disulfide bridges
covalent bonds that may further reinfores the shape of a protein
45
quaternary structure
is the overall protein structure that results form te aggregation of these polypeptide subunits
46
sickle-cell disease
an inherited blood disorder
caused by the substitution of one amino acid
fro the normal one at a particular position in the primary structure of hemoglobin
the protein that carries oxygen in red blood cells
47
denaturation
if the pH, salt concentration, temperature, or other aspects of its environment are altered, the weak chemical bonds and interactions within a protein may be destroyed, causing the protein to unravel and lose its native shaped
48
X ray crystallography
the method most commonly used to determine the 3D shape of a protein
depends on the diffraction of an X ray beam by the atoms of a crystallized molecule
49
gene
the amino acid sequence of a polypeptide is programmed by a discrete unit of inheritence known as a gene
50
nucleic acids
polymers made of monomers called nucleotides
51
deoxyribonucleic acid
DNA provides directions for its own replication and directs RNA synthesis and through RNA, controls protein synthesis
52
ribonucleic acid
RNA is single stranded and helps do the protein thing
53
polynucleotides
nucleic acids are macromolecules that exist as polymers called polynucleotides
54
nucleotides
composed of three parts
nitrogen containing base
five carbon sugar
one or more phosphate groups
55
pyrimidine
has one 6 membered ring of carbon and nitrogen atoms
| C, T, and U
56
Purines
larger that pyrimidine, with 6 member ring fused to a 5 member ring
A, G
57
deoxyribose
sugar in DNA
58
ribose
sugar in RNA
59
double helix
shape of DNA
60
antiparallel
arrangement of DNA sugar phosphate backbones
61
matter
anything that takes up space and has mass
62
element
substance that cannot be broken down to other substances by chemical reactions
63
compound
substance consisting of two or more different elements combined in a fixed ration
64
emergent properties
ones not possessed by its constituents; a copound has physical characteristics different from those of its elements
65
essential elements
an organism needs them to live a healthy life and reproduce, some variation among organisms
oxygen carbon hydrogen and nitrogen make up 96% of living matter
66
trace elements
are required by an organism in only minute qualitites
67
atom
smallest unit of matter that still retains the properties of the element
68
subatomic particles
protons neutrons electrons (basic)
69
atomic nucleus
protons and neutrons packed in dense core
70
dalton
unit of measurement for subatomic particles
71
atomic number
of protons and is written as subscrpt to the left of a symbol for element
72
mass number
sum of protons plus neutrons written as superscript to the left of a symbol for an element
73
atomic mass
mass number, approximation of the total mass of an atom
74
istopes
differeent atomic forms oof same element, different amount of neutrons
75
radioactive isotope
nucleus decays spontaneuously, giving off paricles and energy
76
energy
the capacity to cause change, by doing work
77
potential energy
the energy that matter possessess because of its location or structure
matter has a natural tendency to move to the lowest possible state of potential energy
78
electron shells
where electrons are found, each with characteristic average distance and energy level
electrons exist in the lowest available state of potential energy
79
what happens to energy when electrons move further from the nucleus
absorbed
80
what happens to energy when electrons move towards the nucles
lost
81
valence shell/ valence electrons
outer shell and electrons in that shell
82
chemical bonds
atoms sharing or transfering valence electrons
| strongest bonds are covalent and ionic
83
covalent bond
sharing of a pair of valence electrons by two atoms
84
molecule
two or more atoms held together by covalent bonds
85
molecular versus structural formula
molecular has subscripts and stuff
structural shows u the structure
EX: H2
versus
H----H
86
single versus double bond
difference between sharing one pair of valence electrons or two pairs
87
electronegativity
the attraction of a particular atom for the electrons of a covalent bond
the more electronegative, the more strongly it pulls shared electrons toward itself
88
nonpolar covalent bond
the electrons are shared equally because the two atoms have the same electronegativity
89
polar covalent bond
when an atom is bonded to a more electronegative atom, the electrons of the bond are not shared equally
90
ion
charged atom or molecule
91
cation
positive charged ion
92
anion
negative charged ion
93
ionic bond
cations and anions attract eachother creating this bond
| transfers of electrons causethis attraction
94
ionic compounds
or salts
| compounds formed by ionic bonds
95
hydrogen bonds
noncovalent attraction between a hydrogen and an electronegative atom is called a hydrogen bond
96
van der waals interactions
extremely weakbonds
| only occur when atoms and molecules are very close together
97
chemical reactions
the making and breaking of chemical bonds, leading to changes in the composition of matter
98
reactants and products
what the reaction begins with and hwat it ends with
99
polar molecule
the unequal sharing of electrons and water's v shape make it a polar molecule, meaning that its overall charge is unevenly distributed
100
cohesion
hydrogen bonds hold the water together
101
adhesion
clinging of water to other things
102
surface tension
measure of how difficult it is to stretch or break the surface of a liquid
103
kinetic energy
anything that moves has it
| the energy of motion
104
thermal energy
the kinetic energy associated with the random movement of atoms or molecules
105
temperature
represents the average kinetic energy of molecules, regardless of volume
106
heat
thermal energy in transfer from one body of matter to another
107
calorie
amount of heat it takes to raise the temperature of 1 g of water by 1 degree C
108
kilocalorie
(kcal)
| 1000 calories is the quanitity of heat required to raise the temp of 1 kg of water by 1 dg C
109
joule
another energy unit
one joule equals .239 cal
one cal equals 4.184 j
110
specific heat
the amount of heat that must be absorbed or lost for 1 g of that substance to change its temperature by 1 degree C
111
heat in relation to hydrogen bonds
heat is absorbed to break hydrogen bonds
| heat is released when hydrogen bonds form
112
evaporation
transformation form a liquid to gas
113
heat of vaporization
the quantity of heat a liquid must absorb for 1 g of it to be converted from the liquid to the gaseous state
114
evaporative cooling
as liquid evaporates, the survace of the liquid that remains behind cools down
the hottest molecules, those with the greatest kinetic energy, are the ones ost likely to leave as a gas
115
density of water's forms
less dense as a solid than a liquid
116
solution
the liquid hat is a completely homogeneous mixture of two or more substances
117
solvent
the dissolving agent o fa solution
118
solute
substance dissolved
119
aqueous solution
water is solvent
120
hydration shell
the sphere of water molecules around each dissolved ion
121
hydrophilic
any substance with an affinity of water
122
hydrophobic
substances that repel water, nonpolar usuallyl
123
molecular mass
sum of the masses of all the atoms in a molecule
124
mole (mol)
an exact # of objects: 6.02x10^23
| Avogadro's numba
125
molarity
the number of moles of solute per liter of solution
| unit of concentration most often used by biologists for aqueous solutions
126
hydrogen ion
a single proton withna charge of 1+
127
hydroxide ion
water molecule that lost a proton
128
hydronium ion
H30+
129
acid
substance that increases the hydrogen ion of a solution
| More H+ than OH-
130
base
substance that reduces the hydrogen ion concentration of a solution
(More OH- than H+)
131
pH
negative logarithm of the hydrogen ion concentration
132
Acidic pH and basic pH
0-7 is acidic
7 is neutral
7-14 is basic
133
buffer
substance that minimizes changes in the concentrations of H+ and OH- in a solution
