ch.2 biomolecules

Question 1

Name the four main types of biomolecules

Answer 1

Carbohydrates, proteins, fats, nucleic acids

Question 2

List three of the four elements most characteristic of biomolecules.

Answer 2

Carbohydrates don’t contain nitrogen
Fats also don’t usually contain nitrogen, but also lack oxygen
Proteins are known for their long backbones and goes in pattern of nitrogen then 2 carbons

answer: C,H,O,N

Question 3

Name 4 of the five most common molecules (these are small molecules, not biomolecules) on prebiotic earth, the raw materials for the primordial soup (the starting solution of the Miller-Urey experiments).

Answer 3

Hydrogen H2, methane CH4, water H2O, ammonia NH3

Question 4

Name the kind of molecules that were predicted by Oparin to form in the high-energy reducing atmosphere of pre-biotic earth.

Answer 4

Monosaccharides, glycerol/fatty acids, nucleic acids, amino acids

Question 5

Name (one-letter abbreviation) the four “charged” nucleosides that were the building blocks of the first RNA molecules.

Answer 5

Uracil, guanine, adenine, cytosine

Question 6

Polymerization (dehydration condensation) and depolymerization (hydrolysis) of all four biomolecules occurred chaotically in the primordial soup. What process is the only way a chemical form can persist in this chaos.

Answer 6

The molecule uses its form as a template to replicate itself

Question 7

Describe the important characteristics of the Miller-Urey experiment regarding pre-biotic earth. Be able to explain how the addition of an oxygenated environment would change the outcome of the experiment.

Answer 7

Oxidation is an important characteristic of the experiment because oxygen is very electronegative, meaning it takes electrons from others bc it’s “hungrier” as well as stronger than others. If oxidation had occurred, it would’ve prevented molecules like amino acids, glycerol/fatty acids, proteins, and nucleic acids from fully developing due to it fragmenting it or just preventing these molecules from forming at all.

Question 8

In one or two sentences, describe the steps of a dehydration condensation reaction, and include the initial reactants and final products. Ditto for hydrolysis.

Answer 8

Dehydration condensation requires energy and water is released to combine monomers to make polymers.
Hydrolysis releases energy and water is formed to break apart polymers.

Question 9

carbohydrate monomer

Answer 9

monosaccharide, (CH2O)n

Question 10

protein monomer

Answer 10

amino acid, N-C-C, different R/side chain

Question 11

lipid monomer

Answer 11

“fatty acid”, # of C doesn’t equal # of O, which makes it hydrophobic

Question 12

triglyceride

Answer 12

made from glycerol and 3 fatty acids, has hydrocarbon tail, main energy storage molecule of plants and animals (e storage)

Question 13

phospholipid

Answer 13

made from glycerol backbone (hydrophilic) attached to 2 fatty acids (hydrophobic), allows cell membranes to develop

Question 14

saturated fats

Answer 14

as many H as possible, no double bonds, solid at room temperature

Question 15

unsaturated fats

Answer 15

has O which causes double bond/bend/kink, liquid at room temperature

Question 16

Name the structural feature of an amino acid is responsible for the huge diversity in protein shapes.

Answer 16

amino acids have very different properties depending on their side (R) chains, which allows for a big variety of amino acids

Question 17

side (R) chain

Answer 17

allow huge diversity in protein shapes due to its capability of having different features: hydrophilic (polar), hydrophobic (nonpolar), electrically charged (hydrophilic)

Question 18

Know what type of bonds (hydrogen or covalent) hold the string of amino acids together in a protein (primary structure). Know whether these bonds strong or weak. And know the name for this type of bond occurring specifically between amino acids.

Answer 18

covalent bonds (strong) hold string of amino acids together in a protein. Covalent bonds between each amino acid are peptide bonds and are ALWAYS between the 1st carbon of the amino acid and the N of the other amino acid

Question 19

Know how to position the three phosphates (circled “P” is fine) on the appropriate carbon of the ribose.

Answer 19

connect on carbon-5 of internal ribose

Question 20

Know how to draw the internal ribose and how to number its carbon molecules.

Answer 20

pentagon with O at it’s point, clockwise 1-5 carbons, have an OH at carbon-2/3

Question 21

Know which carbon of the ribose the base attaches to.

Answer 21

carbon-1

Question 22

Name the part of these charged nucleosides that provides the energy to drive polymerization.

Answer 22

nucleoside triphosphate: when they attach themselves to RNA polymers, the covalent bond between 2 of the three triphosphates break off, in which that energy is used to make a covalent bonds between the other nucleotides, allowing polymerization to occur

Question 23

Know which part of a growing RNA polymer a “charged” nucleotide (the triphosphate version) attacks

Answer 23

the 3’ end where the nucleotides connect and form covalent bonds with ribose