ch. 4-5 Flashcards
3 reasons why carbon is flexible (which allows for diverse molecules)
-carbon bonds: 4 valence electrons, so it can form 4 bonds
-not strongly EN
-bonds are at a max distance at 109.5
carbon often pairs with
H, N, O
isomers
molecules with the same atoms but different arrangement of atoms and electrons
structural isomer
-covalent bonds in dif locations
-molecule is dif shape
geometric isomer
-occurs near a double bond: double bond prevents it from being able to rotate along the axis
trans isomer configuration
-important groups are on OPPOSITE sides of the double bond
-chain is straight
cis isomer configuration
-important groups are on the SAME side of double bond
-chain is bent
enantiomers
differ in spatial arrangement around an asymmetric carbon, resulting in 2 molecules that are mirror images.
most important chemical groups?
hydroxyl, carbonyl, carboxyl, amino, sulfyhdryl, phosphate, methyl
what do functional groups (R Groups) do?
attach to carbon chains and have specific properties; directly involved in reactions
what is a macromolecule
polymer built from a monomer
what is a macromolecule
polymer built from a monomer
macromolecules contain…
billions of pieces which each contain many atoms
two ways of changing polymer length
dehydration reaction and hydrolysis reaction
dehydration reaction
-two molecules are covalently bonded together with the loss of a water molecule
-increases length
polymers are disassembled to monomers by…
hydrolysis
hydrolysis reaction
-bond between monomers is broken by the addition of water
-decreases length
most important macromolecules in all living things:
carbohydrates, lipids, proteins, and nucleic acids
most important macromolecules in all living things:
carbohydrates, lipids, proteins, and nucleic acids
carbohydrates? hydrophilic or hydrophobic?
hydrophilic (dissolve in water)
monosaccaride
sugar monomer
monosaccharide differences: chain lengths can vary
triose: 3 carbons
pentose: 5 carbons
hexose: 6 carbons
monosaccharide differences: placement of carbonyl group
-end of carbon skeleton: aldose
-within carbon skeleton: ketose
monosaccharide differences: placement of carbonyl group
-end of carbon skeleton: aldose
-within carbon skeleton: ketose
monosaccharide isomers ?
same atoms, different arrangements
hydroxyl down
alpha
hydroxyl up
beta
disaccharide
2 monosaccharides joined by a glycosidic linkage
3 main disaccharides
sucrose, lactose, and maltose
sucrose =
glucose + fructose
lactose =
glucose + galactose
maltose =
glucose + glucose
polymers with hundreds of thousands of monosaccharides joined by glycosidic linkages
polysaccharide
storage polysaccharides: glucose is stored in animals as
glycogen
storage polysaccharides: glucose is stored in plants as
starch
starch is composed of two types of polysaccharides:
-amylose (unbranched)
-amylopectin (branched)
which is more branched, glycogen or amylopectin?
glycogen
structural polysaccharides: cellulose
tough walls that enclose plant cells; glucose monomers are in beta configuration, which animals cannot digest
chitin is ___ glucose
beta
structural polysaccharides: used in arthropod exoskeletons
chitin
animals cannot digest ___ glucose
beta
important polysaccharides
starch (amylose and amylopectin), glycogen, and cellulose and chitin
lipids are hydrophilic or phobic
hydrophobic
purpose of fats
long term energy storage
a glycerol head can hold up to 3…
fatty acids
fatty acids attached to glycerol via
dehydration reaction
saturated fats are saturated with
max amount of single bonds or hydrogens
saturated fat structure
long, straight, easily pack together
____ fats are solid at room temp
saturated
unsaturated fats may have ___ bonds
some double bonds
why do unsaturated fats not pack together tightly?
the double bond forms a bend
trans fats have some ____ but….
double bonds; similar in other ways to saturated fats
what kind of fats are not common in nature
transfats
phospholipids attach to
glycerol
phospholipids contain
2 fatty acid tails (fatty acid tails are hydrophobic) and 1 phosphate (phosphate is hydrophilic because of it’s partial charges)
the duality of phospholipids (partially hydrophobic and partially hydrophilic) results in
a double layer in water called the phospholipid bilayer
proteins are chains of
amino acid monomers
amino acid monomer contains
amino group, carboxyl group, side chain/R group
amino acid polymer
Amino and carboxyl can bond via a dehydration reaction (called a peptide bond)
polypeptide
polymer of amino acids
there are ___ common amino acids
20
in amino acids, __ is the same, the ___ varies
base; r group
R group properties (amino acids)
Hydrophobic
Hydrophilic (partial charge)
Can form hydrogen bonds and sulfur bonds
primary structure (protein structure)
- Linear chain of amino acids
- Number of amino acids
- Order of amino acids
secondary structure (protein structure)
- Hydrogen bonds between amino and carboxyl groups (not between R groups)
- Stabilizes regions
- Alpha helix: spiral structure
- Beta pleated sheet: wide accordion folds
tertiary structure (protein structure)
- R groups along dif parts the chain interact
o Charges attract/repel
o Hydrophobic group together
o Hydrogen bonds form
o Sulfur bonds form - Interactions fold chain into complex shape
quarternary structure
- Multiple polypeptide subunits interact
- Only occurs in some proteins
the function of nucleic acids
carry information
long term storage
DNA
short term instructions
RNA
pyrimidines have ___ carbone rings:
1: C, T, U
purines have ___ carbon rings
2: A, G
how are nucleic acid polymers formed
Dehydration reaction connects phosphate and sugar and creates sugar-phosphate backbone (coils into a helix)
the 5’ end of the nucleic acid polymer has
phosphate
A, T and U form how many bonds
2 bonds
G and C form how many bonds?
3 bonds
phospholipids attach to
glycerol
glycosidic linkage
covalent bond formed between 2 monosaccharides by a dehydration reaction
fats are composed of
glycerol and fatty acids
fats are composed of
glycerol and fatty acids
important lips
fats, phospholipids, and steroids
important lips
fats, phospholipids, and steroids
fats are composed of
glycerol and fatty acids
