Cell Chemistry Review Flashcards
hold atoms in the same molecule (include ionic bonds, covalent bonds, hydrogen bonds, hydrophobic interactions)
intramolecular bonds
form between two different molecules (include hydrogen bonds, hydrophobic interactions, electrostatic forces, Van Der Waals forces)
intermolecular bonds
formed by attraction of oppositely charged ions, fill valence shell, dissociate in presence of water
ionic bond
strong bond between chemical elements where electrons are shared between atoms to fill valence shells, can have double and triple bonds
covalent bond
types of covalent bonds
electronegativity, non-polar, polar
the force of attraction of a nucleus on the electrons moving around it
electronegativity
electrons are shared equally and there is no polarity, occurs between atoms of similar electronegativity
non-polar bond
electrons are shared unequally between two atoms so there is a positive and negative pole (zero net charge), occurs with atoms of varying electronegative values
polar bond
Why is polarity important?
water is a polar solvent, macromolecules are polar and readily dissolve in water, promotes molecular stability through hydrogen bonds
composed of mostly ionic bonds, generally water soluable, hydrophilic
ionic compounds
mostly polar covalent bonds, generally water soluable, hydrophilic
polar compounds
mostly non polar covalent bonds, not water soluble (hydrophobic)
nonpolar compounds
composed of part hydrophilic and hydrophobic regions, part water soluable while other parts not
amphipathic compound
What makes up a solution?
a solute and a solvent
small molecules that are the building blocks of larger molecules
monomers
large molecules
macromolecules
larger molecules composed of covalently bonded similar or identical monomers
polymers
a weak bond that forms due to electrostatic interactions between hydrogen atoms (positive polarity) and more electron-attracting atoms (negative charge)
hydrogen bond
weak bonds that occur when nonpolar molecules or regions associate tightly in a polar solvent, nonpolar molecules disrupt hydrogen bonding among water molecules, squeeze together by water molecules trying to minimize volume
hydrophobic interactions
weak attractive forces that occur between atoms when they are nearly touching, due to temporary polarities in atoms and molecules
Van der Waals forces
__________is a component of all macromolecules
carbon
functional group that can act as an acid, makes the molecule more polar
carboxyl group
OH-C=O
makes molecule an alcohol and more polar
hydroxyl group
-C-OH
makes molecule an organic base and more polar
amino group
-N-HH
carbon oxygen carbon with a double bonded oxgygen on the first carbon
ester
carbon oxygen carbon with 2 hydrogens on both carbons
ether
water, salts, acids, bases, and buffers
inorganic molecules
carbohydrates, lipids, polypeptides, and proteins
organic molecules
makes up 90% of a cell, has a high specific heat, good solvent for polar and ionic molecules, can form hydrogen bonds, key features are polarity and cohesion
water
importance of cohesion
water molecules have a high affinity for one another due to hydrogen bonds between, allows for high surface tension and specific heat
ionic compounds consisting of a cation and an anion held together by and ionic bond, dissolve in water into there respective ions
salts
proton donors, increases the concentration of H+ ions in solutions
acids
proton acceptors, decrease the concentration of H+ ions in a solution
bases
compounds that resist changes in pH by sometimes behaving like an acid or a base
buffer
What are the 4 kinds of macromolecules?
proteins, nucleic acids, lipids, carbohydrates
organic compounds, C1H2O1, polar and hydrophilic, 4-7 carbon atoms, used for energy storage and polysaccharide building blocks
monosaccharides and disaccharides
carbohydrates with many monomeric units connected by glycosidic bonds
polysaccharides
carbohydrates containing 2 monosaccharides
disaccharide
carbohydrates containing 3 monosaccharides
trisaccharides
carbohydrates containing several monosaccharides
oligosaccharides
covalent bonds linking sugars together in a polysaccharide, alpha and beta linkage
glycosidic bond
polysaccharide composed of glucose monomers, joined to each other by alpha glycosidic bond, function is for energy storage
starch
examples include cellulose and chitin, polysaccharide composed of glucose monomers joined to each other by beta glycosidic bonds
structural polysaccharide
polysaccharide + protein
glycoproteins
polysaccharide + lipid
glycolipid
include simple fats, oils, sterols, and phospholipids, both nonpolar and hydrophobic, fatty acids are major constituents
lipids
3 fatty acids bound to the C3 alcohol glycerol, used for energy storage, also known as triglycerides
simple lipids
a lipid characteristic with no double bond, linear
saturated
a lipid characteristic with one or more double bonds between the carbohydrates
unsaturated
quality that means both hydrophilic and hydrophobic characteristics are displayed
amphipathic
simple lipids that contain additional elements or small hydrophilic compounds
complex lipids
complex lipids containing PO4 groups, seen in membranes and are amphipathic
phospholipids
made up of a polymer of nucleotides
nucleic acids
a polymer of deoxiribonucleotides, genetic material in all cells and some viruses, double strand, complementary strands, Hydrogen bond connection
DNA
polymer of ribonucleotides, plays role in protein synthesis, genetic material of most viruses, composed of one C5 sugar, nitrogen base, and phosphate group, typically a single strand, exhibits secondary structure (folds over), has four classes
RNA
nitrogen base bonded to C5 sugar
nucleoside
nitrogen base attached to C5 sugar by N-glycosidic linkage, are a major component of nucleic acids, key forms of chemical energy
nucleotide
adenine and guanine, contain 2 fused heterocyclic rings
purine bases
cytosine, thymine, and uracil, contain a 6 membraned heerocyclic ring
pyrimidine bases
phosphate linkage that connects 2 sugars with ester linkage
phosphodiester bond
sequence of nucelotides in RNA/DNA molecule
primary structure
What are the 4 classes of RNA?
mRNA, tRNA, rRNA, and small RNA
A peptide bond releases ___________
water
a macromolecule that mostly consists of carbon, hydrogen, oxygen, and nitrogen, contain 2 important functional groups (amino group and carboxylic group)
amino acids
related, but not completely identical, include optical isomers known as enantiomers or sterioisomers
isomers
enzymes capable of interconverting specific enantiomers
racemases
structural term meaning a series of amino acids (10s, 100s, 1000s, 10,000s amino acids longs) joined to each other by peptide bonds
polypeptide
a functional unit consisting of one or more polypeptide having one or more functions
protein
catalytic proteins, catalysts for chemical reactions
enzymes
integral parts of cellular structures (such as eukaryotic chromosomes)
structural proteins
two amino acids bonded by peptide linkage
dipeptide
three amino acids bonded by peptide linkage
tripeptide
many amino acids bonded by peptide linkage
polypeptide
linear array of amino acids in a polypeptide
primary structure
folds in polypeptide that form a more stable structure, held together by hydrogen bonding between amino group hydrogen and carbonyl oxygen
secondary structure
additional folding of polypeptide to result in greater stability and unique three dimensional shape, forms exposed regions or grooves in the molecule that are important for binding other molecules
tertiary structure
covalent bonds between -SH group from two different amino acids
disulfide bond
occurs in proteins composed of two or more polypeptides
quaternary structure
each polypeptide in the protein, held together by covalent or noncovalent linkages
subunit
protein containing two identical subunits
homodimer
protein containing two nonidentical subunits
heterodimer
What factors can lead to the denaturation of polypeptide chains?
extreme change in pH value, temperature or exposure to chemicals. results in loss of biological function and can be reversible or irreversible
