Lecture 2- Macromolecules

Question 1

water characteristics

Answer 1

-solvent of life
-polar = unequal distribution of e- across a bond
-can associate with other water molecules because opposites attract

Question 2

organic macromolecules contain ____

Answer 2

-contain C-H
-C is the backbone of organic molecules
-C is weakly electronegative

Question 3

why is life carbon-based?

Answer 3

1. can bond to 4 other atoms
2. can bond to form C-C chains
3. can form double + triple bonds

Question 4

monomer

Answer 4

single building blocks of a macromolecule

Question 5

polymer

Answer 5

a chain of monomers composed of similar but non-identical subunits

Question 6

why are polymers more biologically important than monomers?

Answer 6

allow for variation to promote biological diversity

Question 7

synthesis-condensation reactions/dehydration reaction

Answer 7

-add monomers to a growing chain (formation of a covalent bond)
-water is a product (losing water)
-requires energy

Question 8

breakdown-hydrolysis reaction

Answer 8

-cleavage of covalent bonds b/w monomers in a polymer
-water is a reactant
-releases energy

Question 9

carbohydrates/polysaccharides/sugars function

Answer 9

energy storage, maintain cell structure, cell-cell recognition

Question 10

monosaccharides

Answer 10

monomers of carbs have a C chain of 3-7C long
-can be linear or ring-shaped
-multiples of CH2O
-ex:glucose

Question 11

disaccharides

Answer 11

formed by a glycosidic covalent bond b/w monosaccarides
-eg: sucrose

Question 12

bond type of disaccharides

Answer 12

glycosidic bonds (type of covalent bond)

Question 13

polysaccharides and examples

Answer 13

polymers of monosaccharides
-starch, glycogen, cellulose, chitin

Question 14

starch

Answer 14

-nutritional polysaccharide for energy storage in plants
-polymer of glucose
-contains alpha 1-4 glycosidic bonds

Question 15

what is glycogen and its function

Answer 15

-nutritional polysaccharides of animals
-fxn: energy storage in animals
-polymer of glucose that is highly branched
-broken down and released from the liver into the blood as glucose during fasting
-used up by all cells
-connected by alpha 1-4 glycosidic bonds

Question 16

cellulose

Answer 16

-structural polysaccharide
-polymer of glucose
-function-provide structure to plant cell wall
-contains beta 1-4 glycosidic bonds

Question 17

chitin

Answer 17

-structural polysaccharide
-polymer of monosaccarides
-found in insect exoskeleton and fungal cell wall

Question 18

peptidoglycan

Answer 18

-structure to bacterial cell wall
-polymer of NAG and NAM-disaccharides

Question 19

lipids classification and function

Answer 19

-classification as a lipid because they are: hydrophobic (non-polar and aggregate away from H2O)
-made of mostly H-C (equal weak electronegativity therefore no dipoles or partial charge)

Question 20

fatty acids

Answer 20

single chains of mostly HC with a COOH end
-16-18 C long
-can attach (esterify) to a glycerol backbone ester bond

Question 21

fats function

Answer 21

triglyceride=animal fat
-fxn-energy storage in animals and insulation

Question 22

saturated fatty acids

Answer 22

-single bonded
-solid at room temp
-linear fatty acids

Question 23

unsaturated fatty acids

Answer 23

-double bonded
-liquid at room temp
-kink in the fatty acid

Question 24

phospholipids

Answer 24

-structural component of biological membrane
-amphipathic
-2 HC chains attached to a glycerol backbone via ester bonds

Question 25

phospholipids

Answer 25

-a structural component of biological membrane
-amphipathic
-2 HC chains attached to a glycerol backbone via ester bonds

Question 26

steroids

Answer 26

backbone of 4 fused HC rings
-slightly amphipathic
-planar/flat
-fxn: hormones and maintains fluidity and thickness

Question 27

proteins

Answer 27

-polymers of amino acids
-involved in every biological task

Question 28

primary structure of proteins

Answer 28

determined by the DNA sequence of a gene
-polymer of a.a.

Question 29

primary sequence dicates______

Answer 29

folding

Question 30

folding dictates ______-

Answer 30

function

Question 31

secondary structure of proteins

Answer 31

-stabilized by interaction between the backbones of the peptide chain
-local folding of a.a. chain into an alpha helix or beta sheet

Question 32

tertiary structure of proteins

Answer 32

-3D folding
-hydrophobic R groups bury into the middle of the protein to aggregate away from the water

Question 33

list the forces and interactions that stabilize the tertiary structure of proteins

Answer 33

covalent, ionic bonds, hydrogen bonds, hydrophobic interactions

Question 34

quaternary structure of proteins

Answer 34

-some function as multisubunit complexes
-complex stabilized by same R group interactions as tertiary structure
-eg:ribosomes

Question 35

what are chaperones?

Answer 35

proteins that assist in folding other proteins
-only some proteins require
-proper folding is essential for proper function

Question 36

nucleic acids function

Answer 36

-store and transmit hereditary info

Question 37

what is DNA

Answer 37

-polymer of nucleotides
-transmits info between cells and cell generations

Question 38

what is RNA

Answer 38

-polymer of ribonucleotides
-transmits info within the cell
-translation
-splicing
-gene regulation

Question 39

nucleic monomers are joined into a sugar-phosphate backbone by _______

Answer 39

phosphodiester bonds

Question 40

RNA is single-stranded because:

Answer 40

• 2’ OH makes the helix more open
• 2’ OH makes RNA more reactve
• can base pair with itself, other RNA, and DNA