lec 3- introduction to macromolecules

Question 1

what are macromolecules?

Answer 1

large highly organized molecules that form the structure and carry out the activities of cells

Question 2

what are the 4 types of macromolecules?

Answer 2

proteins, nucleic acids, polysaccharides, and lipids

Question 3

are all macromolecules short lived?

Answer 3

no, only three are short lived, DNA lives long

Question 4

what are carbohydrates?

Answer 4

sugar molecules that include monosaccharides, disaccharides, polysaccharides

Question 5

what macromolecule is the most abundant form of organic matter on earth?

Answer 5

carbohydrates or polysaccharides

Question 6

what is the structure of a sugar molecule?

Answer 6

it has a backbone of carbon atoms linked together in single bonds

Question 7

what is a ketose?

Answer 7

a sugar molecule with the carbonyl group located at an internal position

Question 8

what is an aldose?

Answer 8

a sugar molecule with the carbonyl group located at an external position

Question 9

what formation does glucose always take in the body?

Answer 9

a ring structure

Question 10

what does the 5th carbon in glucose do to the 1 carbon in a ring structure?

Answer 10

a nucleophilic attack

Question 11

what configuration does D-glucose have when the primary carbon OH is below the plane?

Answer 11

alpha-D-glucose

Question 12

what configuration does D-glucose have when the primary carbon OH is above the plane?

Answer 12

beta-D-glucose

Question 13

what bond links sugar molecules together?

Answer 13

glycosidic bonds

Question 14

how do glycosidic bonds form?

Answer 14

they are formed between two OH groups on two separate monosaccharides

Question 15

what carbohydrate cannot be digested and why?

Answer 15

cellubiose, due to no enzyme existing for it

Question 16

what monosaccharides does the disaccharide Sucrose contain?

Answer 16

glucose and fructose

Question 17

what monosaccharides does the disaccharide lactose contain?

Answer 17

galactose and glucose

Question 18

what can an anomeric carbon no longer do when it takes place in a glycosidic bond?

Answer 18

it can no longer mutarotate

Question 19

what are the two types of glycosidic bonds?

Answer 19

O-glycosidic bond (attached with hydroxyl)
and N-glycosidic bond (attached with nitrogen)

Question 20

do anomeric carbons always bond with a sugar?

Answer 20

no, they can bond with a protein as well

Question 21

what do branched glucose polymers make in an animal?

Answer 21

glycogen

Question 22

what do branched or unbranched glucose polymers make in a plant?

Answer 22

starch

Question 23

what is amylose?

Answer 23

amylose is a linear polymer, with alpha (1–>4) linkages between glucose monomers

Question 24

what is amylopectin and glycogen?

Answer 24

They are branched polymers, with alpha (1–>4) linkages and alpha(1–>6) linkages

amylopectin has a branch every 25th glucose, while glycogen has a branch every 10th glucose

Question 25

what is starch made of?

Answer 25

amylose and amylopectin

Question 26

what are the nutritional carbohydrates?

Answer 26

starch and glycogen

Question 27

what are the structural carbohydrates?

Answer 27

cellulose, chitin, and GAGs

Question 28

what is cellulose?

Answer 28

plant product made of unbranched polymers

Question 29

what is chitin?

Answer 29

component of invertebrate exoskeleton made

Question 30

what is GAGs?

Answer 30

composed of two different sugars and found in extracellular space

Question 31

what is a glycan?

Answer 31

a carbohydrate with less than a dozen monosaccharides

Question 32

what is glycomics?

Answer 32

the study of glycans produced by an organism

Question 33

what are the types of lipids?

Answer 33

fats, steroids, and phospholipids

Question 34

what are the characteristics of fats?

Answer 34

fatty acids are long, unbranched hydrocarbon chains

Question 35

why can soaps dissolve grease?

Answer 35

because the nonpolar part of the fatty acid embeds itself into the grease while the polar part interacts with water, this causes the creation of a micelle where grease is on the inside and now can be washed away

Question 36

what are the two forms of fatty acids?

Answer 36

saturated = single bonds unsaturated = double bonds "kink"

Question 37

what stores fat in the body

Answer 37

adipocyte cells

Question 38

what are steroids made of?

Answer 38

built around 4 ringed hydrocarbon skeleton that is attached to cholesterol

Question 39

do plant cells have cholesterol?

Answer 39

largely absent, so no, hence why vegetable oils are cholesterol free

Question 40

what are phospholipids made of?

Answer 40

two hydrocarbon tails attached to a glycerol which is attached to a phosphate group which is also attached to a small polar group like choline

Question 41

are phospholipids amphipathic?

Answer 41

yes

Question 42

what are proteins?

Answer 42

are macromolecules that carry out cell activities

Question 43

what are the 6 types of proteins?

Answer 43

-enzymes (catalyze reactions) -structural proteins (provide mechanical support) -signalling proteins (determine what a cell reacts to) -regulatory proteins (determine how that signal is conveyed) -filaments and molecular motors (provide biological movements) -transport proteins (allow molecules in and out of the cell)

Question 44

what are the 4 levels of organization of a protein?

Answer 44

primary (amino acid chain) secondary (a-helix and B-sheets) tertiary (folding) quaternary (assembled subunits)

Question 45

what are the two forms an amino acid can exist in?

Answer 45

D or L

Question 46

what form are amino acids in the synthesis of a protein?

Answer 46

L form

Question 47

what are amino acids made of?

Answer 47

an amine group, a carboxyl group, and a R group

Question 48

why is the hydropathy index important?

Answer 48

useful in determining the hydrophobic interior portion and hydrophilic parts of a protein

Question 49

what is protein secondary structure?

Answer 49

alpha helices and beta sheets

Question 50

T or F: alpha helices do not cross through lipid bilayers

Answer 50

false

Question 51

what is a tertiary structure of protein?

Answer 51

folding

Question 52

how can you determine tertiary protein structure?

Answer 52

by NMR spectroscopy or X ray crystallography

Question 53

how are tertiary structures stabalized?

Answer 53

by noncovalent and covalent interactions

Question 54

what are the two categories of shape for a protein?

Answer 54

fibrous = long globular = compact

Question 55

what is myoglobin?

Answer 55

a globular protein that stores oxygen

Question 56

what is protein quaternary structure?

Answer 56

assembled subunits

Question 57

what is a domain?

Answer 57

a substructure produced by any part of a polypeptide chain that can fold independently into a stable structure that has a function

Question 58

what is src protein kinase?

Answer 58

it is an enzyme

Question 59

how many domains does src protein have?

Answer 59

4 domains, 2 of the domains make kinase

Question 60

what is a homodimer?

Answer 60

a protein with 2 identical subunits

Question 61

what is a heterodimer?

Answer 61

a protein composed of 2 nonidentical subunits

Question 62

what causes protein denaturation?

Answer 62

urea, detergents, organic solvents, radiation, heat

Question 63

what do chaperones do?

Answer 63

bind to proteins and assist them in folding properly

Question 64

what does misfolding of proteins do?

Answer 64

cause diseases like alzheimers

Question 65

what are nucleic acids?

Answer 65

genetic information like DNA and RNA

Question 66

what are nucleotides?

Answer 66

the polymers that make nucleic acids

Question 67

what are nucleic acids made of?

Answer 67

a phosphate group, a sugar (deoxiribose in DNA and ribose in RNA) and a base