biomolecules Flashcards
polarity
distribution of charge within a molecule due to differences in electronegativity between atoms
functional groups
specific group of atoms that contribute to a predictable behavior of the molecule
most polar type of molecules
ones with charges like carbonic acid and NH3+
steroids
cholesterol derived non-polar hormones. consist of 4 hydrocarbon rings
amphipathic molecules
molecule with significant polar and nonpolar regions
ex: fatty acids
what kinds of solvents are physiologically toxic?
nonpolar solvents like hexane
what kind of compounds are lipophilic?
hydrocarbons (alkanes,alkenes, alkynes)
structure of an amino acid
an amino group, hydrogen, R group, and cooh group bound to a central carbon
what part of the amino acid determines its properties?
r group
r group classifications
positively charged, negatively charged, polar, nonpolar
which amino acid is achiral
glycine
which amino acids are aromatic
tyrosine, tryptophan, phenylalenine
which amino acids contain sulfur?
met and cyst
which amino acid breaks up secondary structure
proline (formation of proline kinks)
nonpolar amino acids
G, A,V, I, L, M, P, F, Y, W
polar amino acids
S, T, N, Q, C
positively charged amino acids?
R, K, H
negatively charged amino acids?
D, E
which amino acid is responsible for the formation of disulfide bridges in terciary protein structure?
cysteine- cystine
what bond joins amino acids to make proteins?
peptide bonds (dehydration)
- between cooh of previous amino acid and NH3 of next amino acid
direction of proteins
N terminus to C terminus
primary protein structure
sequence of amino acids, unchanged following denaturation
secondary protein structure
hydrogen bonding between the amine and cooh groups in the amino acid backbone that create alpha helicies and beta sheets
terciary structure
interactions between side chains, all proteins have this structure
quartenary protein structure
not all proteins possess this structure, interactions between multiple peptide subunits
lipids functions
storage, energy, structure, signalling
types of lipids
- fatty acids + derivatives
- cholesterol + derivatives
- eocosinoids (prostaglandins)
- terpenes and terpenoids
fatty acids
long chain carboxylic acids, can be branched or unbranched
TAGs
3 fatty acids bonded to a glycerol backbone. important for fat storage. bond can be broken via saponification
phospholipids
derivative of TAGS
2 fatty acids and a p group bound to glycerol. most common lipid in membrane
spingolipid
sphingosine bound to a fatty acid
waxes
naturally occuring mixtures of lipids that include fatty acids, long-chain fatty alcohols, aromatic compounds. secreted by plants
cholesterol
precursor for vitamin d and steroids, 4 hydrocarbon rings. nonpolar and important in signalling
eocosinoids (prostaglandins)
derived from arachodonic acid, important in signalling and controlling inflammation
terpens/ terpenoids
hydrocarbons composed of repeating isoprene (C5H8) units
- ex: squalene
- precursor for vitamin A
squalene
terpene precursor of cholesterol
fat soluble vitamins
A, D, E, K
carbohydrates
major source of energy, composed of C(h2O) units with at least one carbonyl and one hydroxyl group
aldose sugar
sugar where the carbonyl is terminal
ex- glucose
ketose sugar
sugar where the carbonyl is inside the chain (not terminal )
ex- fructose
what isomer do carbs exsist in?
D
which configuration do amino acids exsist in ?
L
fructose
ketohexose that is made by plants and found in fruits
galactose
aldohexose epimer of glucose
sucrose
glucose and fructose (alpha 1-4)
maltose
glucose + glucose
lactose
glucose + galactose
amylose
linear polysaccharide linked by a(1-4) bonds
- major component of starch
amylopectin
branched polysaccharide linked by a 1-4 and branches a 1-6 bonds
- makes up majority of starch and is easily broken down
starch
major storage polysaccharide in plants. composed of amylose and amylopectin
- most common carbohydrate in diet q
glycogen
animal carbohydrate storage with a1-4 and branched 1-6
synthesized in liver and stored in liver and muscle
cellulose
structural polysaccharide made by plants b1-4 bonds that cannot be digested by humans
- makes up dietary fiber
nucleic acid functions
store and transmit genetic information
nucleotide
made of nitrogenous base, phosphate group, and 5 carbon sugar (pentose)
nucleoside
nitrogenous base and pentose
nitrogenous bases
A, T, G, C, U
purines
2 ring structure
A and G
pyrimidines
1 ring structure
T, C, U
structural significance of uracil
demethylated version of thymine
difference between RNA and DNA pentose?
ribose has a 2’ OH group while DNA pentose is missing 2’ OH
bond that connects phosphate group and pentose sugar in nucleic acids
?
phosphodiester bond between phosphate of previous group and pentose of next group
adds a p group to the 3’ end
which direction are phosphodeister bonds made
5’ to 3’
how many hydrogen bonds are formed between A and T
2
how many hydrogen bonds are formed between g and C
3
what keeps the two strands of DNA together in a double helix
hydrogen bonding between nitrogenous bases
DNA double strands are..
antiparallel
one is 5’-3’ other is 3’-5’
b DNA
most common type
10 bases per turn
A- DNA
tighter than regular dna with 11 bases per turn
z DNA
loser with 12 bases per turn
subtypes of DNA
mitochondrial DNA
subtypes of RNA
mRNA, tRNA, r RNA, miRNA, siRNA, hnRNA
18 of the 19 amino acids that are chiral are S orientation.. which amino acid is the exception?
L-cystine is R oriented
how do double bonds effect the boiling point of fatty acids
unsaturation will lower boiling point
which type of character increases boiling point of fatty acids? trans or cis
trans
