BIOC 201 QUESTIONS WITH CORRECT
ANSWERS PROVIDED
Why do fat droplets in a system of water eventually come together to form one fat
droplet? ✔✔nonpolar spontaneously interacts with nonpolar via *hydrophobic
interaction*
Why do fat droplets in a system of water come together, because isn't entropy
supposed to increase? ✔✔1. fats are (kind of) repelled by water
2. fats altogether have lower surface area
3. ice-like water around each fat droplet increases in disorder
Do lipids combine together? ✔✔no
Are C-H, C-C bonds polar or nonpolar ✔✔nonpolar
trace elements ✔✔elements required by organism in smallest quantities
valence ✔✔atom's bonding capacity (number of unpaired electrons, number of covalent
bonds atom can form to complete shell)
What is the strength of ionic bonds in aqueous phase? ✔✔weak
What are the four emergent properties of water for life? ✔✔1. cohesion
2. moderation of temperature
3. higher density of water than ice
4. Universal solvent
surface tension ✔✔measure of how difficult it is to stretch/break surface of liquid
evaporative cooling ✔✔as liquid evaporates, surface of liquid that remains behind cools
down
Why is water more dense than ice? ✔✔H bonding in ice keeps molecules *apart*, lack
of speed prevents them from breaking H bonds, leaving them in a lattice
What are two qualities of hydrophobic substances? ✔✔nonionic and nonpolar
What are common ingredients of organic molecules? ✔✔*C*, H, O, N, (S, P)
,What did Miller and Urey conclude? ✔✔complex organic molecules arise spontaneously
under conditions of early Earth
hydrocarbon ✔✔organic molecule containing only carbon and hydrogen
Where are hydrocarbons found? ✔✔petroleum, tails of fats
isomers ✔✔compounds with same literal formula, but different structure
structural isomers ✔✔differ in covalent arrangement of atoms
cis-trans isomers ✔✔carbons have covalent bonds to same atoms, but atoms differ in
spatial arrangement
enantiomers ✔✔isomers that are mirror images of each other
asymmetric carbon ✔✔carbon attached to 4+ different atoms
functional group ✔✔chemical group involved in chemical rxns directly
hydroxyl group ✔✔polar, *alcohol*
carbonyl group ✔✔*aldehydes*, *ketones*
carboxyl group ✔✔carboxylic *acid*
amino group ✔✔*amine*
sulfhydryl group ✔✔*thiols*
phosphate group ✔✔(organic phosphate)
methyl group ✔✔(methylated compound)
macromolecules ✔✔huge carbohydrates, proteins, or nucleic acids
polymer ✔✔long chain of identical monomers in carbohydrates, proteins, and nucleic
acids
What happens when 5 or 6 carbon sugars are in aqueous solutions? ✔✔they form rings
glycosodic linkage ✔✔formation of disaccharide by dehydration synthesis between first
and fourth carbon of respective sugars
, how do plants and muscles store polysaccharides? ✔✔starch, glycogen
Difference between alpha and beta glucose? ✔✔orientation of H and OH upon the first
carbon is flipped
Difference between alpha and beta linkage? ✔✔starch, cellulose
chitin ✔✔structural polysaccharide in arthropods and fungi
lipids ✔✔nonpolymers and hydrophobic molecules
triglyceride ✔✔glycerol + 3 fatty acids
fatty acid ✔✔16-18 carbons in length (carboxyl group makes it a fatty acid)
What phase are saturated and unsaturated fatty acids? ✔✔solid, liquids (respectively)
Purpose of fats? ✔✔energy storage (1g fat has more than 2x energy as 1g
polysaccharide)
phospholipid ✔✔2 fatty acids attached to glycerol, attached to a polar group (with
phosphate ion and choline)
steroid ✔✔lipid with carbon skeleton consisting of 4 fused rings (i.e. cholesterol)
polypeptide ✔✔polymer of amino acids
amino acid ✔✔R-group (side chain/residue)
nonpolar amino acid ✔✔nonpolar side chains
What are the three types of polar amino acids? ✔✔uncharged, acidic, basic
What are polar, uncharged amino acids? ✔✔polar, uncharged side chains
What are acidic amino acids? ✔✔negatively charged amino acid side chains
What are basic amino acids? ✔✔positively charged amino acid side chains
secondary structure ✔✔hydrogen bond stabilization of regions between atoms on
backbone
ANSWERS PROVIDED
Why do fat droplets in a system of water eventually come together to form one fat
droplet? ✔✔nonpolar spontaneously interacts with nonpolar via *hydrophobic
interaction*
Why do fat droplets in a system of water come together, because isn't entropy
supposed to increase? ✔✔1. fats are (kind of) repelled by water
2. fats altogether have lower surface area
3. ice-like water around each fat droplet increases in disorder
Do lipids combine together? ✔✔no
Are C-H, C-C bonds polar or nonpolar ✔✔nonpolar
trace elements ✔✔elements required by organism in smallest quantities
valence ✔✔atom's bonding capacity (number of unpaired electrons, number of covalent
bonds atom can form to complete shell)
What is the strength of ionic bonds in aqueous phase? ✔✔weak
What are the four emergent properties of water for life? ✔✔1. cohesion
2. moderation of temperature
3. higher density of water than ice
4. Universal solvent
surface tension ✔✔measure of how difficult it is to stretch/break surface of liquid
evaporative cooling ✔✔as liquid evaporates, surface of liquid that remains behind cools
down
Why is water more dense than ice? ✔✔H bonding in ice keeps molecules *apart*, lack
of speed prevents them from breaking H bonds, leaving them in a lattice
What are two qualities of hydrophobic substances? ✔✔nonionic and nonpolar
What are common ingredients of organic molecules? ✔✔*C*, H, O, N, (S, P)
,What did Miller and Urey conclude? ✔✔complex organic molecules arise spontaneously
under conditions of early Earth
hydrocarbon ✔✔organic molecule containing only carbon and hydrogen
Where are hydrocarbons found? ✔✔petroleum, tails of fats
isomers ✔✔compounds with same literal formula, but different structure
structural isomers ✔✔differ in covalent arrangement of atoms
cis-trans isomers ✔✔carbons have covalent bonds to same atoms, but atoms differ in
spatial arrangement
enantiomers ✔✔isomers that are mirror images of each other
asymmetric carbon ✔✔carbon attached to 4+ different atoms
functional group ✔✔chemical group involved in chemical rxns directly
hydroxyl group ✔✔polar, *alcohol*
carbonyl group ✔✔*aldehydes*, *ketones*
carboxyl group ✔✔carboxylic *acid*
amino group ✔✔*amine*
sulfhydryl group ✔✔*thiols*
phosphate group ✔✔(organic phosphate)
methyl group ✔✔(methylated compound)
macromolecules ✔✔huge carbohydrates, proteins, or nucleic acids
polymer ✔✔long chain of identical monomers in carbohydrates, proteins, and nucleic
acids
What happens when 5 or 6 carbon sugars are in aqueous solutions? ✔✔they form rings
glycosodic linkage ✔✔formation of disaccharide by dehydration synthesis between first
and fourth carbon of respective sugars
, how do plants and muscles store polysaccharides? ✔✔starch, glycogen
Difference between alpha and beta glucose? ✔✔orientation of H and OH upon the first
carbon is flipped
Difference between alpha and beta linkage? ✔✔starch, cellulose
chitin ✔✔structural polysaccharide in arthropods and fungi
lipids ✔✔nonpolymers and hydrophobic molecules
triglyceride ✔✔glycerol + 3 fatty acids
fatty acid ✔✔16-18 carbons in length (carboxyl group makes it a fatty acid)
What phase are saturated and unsaturated fatty acids? ✔✔solid, liquids (respectively)
Purpose of fats? ✔✔energy storage (1g fat has more than 2x energy as 1g
polysaccharide)
phospholipid ✔✔2 fatty acids attached to glycerol, attached to a polar group (with
phosphate ion and choline)
steroid ✔✔lipid with carbon skeleton consisting of 4 fused rings (i.e. cholesterol)
polypeptide ✔✔polymer of amino acids
amino acid ✔✔R-group (side chain/residue)
nonpolar amino acid ✔✔nonpolar side chains
What are the three types of polar amino acids? ✔✔uncharged, acidic, basic
What are polar, uncharged amino acids? ✔✔polar, uncharged side chains
What are acidic amino acids? ✔✔negatively charged amino acid side chains
What are basic amino acids? ✔✔positively charged amino acid side chains
secondary structure ✔✔hydrogen bond stabilization of regions between atoms on
backbone
