Chapter 2

Question 1

Organic molecules (Name the 4)

Answer 1

Carbs
Lipids
Proteins
Nucleic Acids

Question 2

The most abundant molecule in cells

Answer 2

Water

Question 3

Slightly positive atom in water

Answer 3

Hydrogen

Question 4

Slightly negative atom in water

Answer 4

Oxygen

Question 5

Bonds that form between polar organic molecules

Answer 5

Hydrogen bonds

Question 6

Solubility of nonpolar molecules

Answer 6

Poor

Question 7

Dehydration reactions (H2O is removed) / sugars are linked by a

Answer 7

glycosidic bond

Question 8

polymers of a few sugars.

Answer 8

Oligosaccharides

Question 9

polymers of hundreds or thousands of sugars.

Answer 9

Polysaccharides

Question 10

storage of glucose in animal cells.

Answer 10

glycogen

Question 11

storage in plant cells

Answer 11

Starch

Question 12

Both starch and glycogen are:

Answer 12

composed entirely of glucose molecules in the α configuration

Question 13

main structural component of plant cell walls

Answer 13

cellulose

Question 14

3 main roles of lipids

Answer 14

1.) Energy storage
2.) Cell membranes
3.) Cell signaling

Question 15

long hydrocarbon chains (16 or 18 carbons) with a carboxyl group (COO–) at one end.

Answer 15

fatty acids

Question 16

fatty acids with one or more double bond

Answer 16

unsaturated

Question 17

fatty acids with no double bonds

Answer 17

saturated

Question 18

Three fatty acids linked to a glycerol molecule.

Answer 18

Triacylglycerols

Question 19

______ are more efficient energy storage than ____________, yielding more than twice as much energy per weight of material broken down.

Answer 19

Fats; carbohydrates

Question 20

the principal components of cell membranes.

Answer 20

phospholipids

Question 21

part water-soluble / part water-insoluble.

Answer 21

Amphipathic molecules

Question 22

2 fatty acids bound to two carbons in glycerol.

Answer 22

Glycerol phospholipids

Question 23

the only nonglycerol phospholipid in cell membranes

Answer 23

Sphingomyelin

Question 24

two hydrocarbon chains and a carbohydrate polar head group (amphipathic).

Answer 24

glycolipids

Question 25

four hydrophobic hydrocarbon rings and a polar hydroxyl (OH) group (amphipathic).

Answer 25

cholesterol

Question 26

examples of steroid hormones

Answer 26

estrogen, testosterone

Question 27

steroid hormones are derivatives of:

Answer 27

cholesterol

Question 28

carries information from DNA to the ribosomes.

Answer 28

mRNA

Question 29

types of RNA involved in protein synthesis

Answer 29

rRNA and tRNA

Question 30

DNA and RNA are polymers of:

Answer 30

nucleotides

Question 31

Nucleotides consist of purine and pyrimidine bases linked to:

Answer 31

phosphorylated sugars.

Question 32

2 purines

Answer 32

adenine and guanine

Question 33

2 pyrimidines

Answer 33

cytosine and thymine

Question 34

RNA has _____ in place of thymine

Answer 34

uracil

Question 35

Bases are linked to sugars to form:

Answer 35

nucleosides

Question 36

bonds between the 5′ phosphate of one nucleotide and the 3′ hydroxyl of another.

Answer 36

phosphodiester

Question 37

polymers of only a few nucleotides.

Answer 37

Oligonucleotides

Question 38

may contain thousands or millions of nucleotides, like DNA or RNA

Answer 38

polynucleotides

Question 39

Polynucleotides are always synthesized in the _______ direction.

Answer 39

5′ to 3′

Question 40

the most diverse macromolecule

Answer 40

Protein

Question 41

Proteins are polymers of 20 different ____________

Answer 41

amino acids.

Question 42

Amino acids consists of: (5 things)

Answer 42

α carbon bonded carboxyl group an amino group a hydrogen a distinctive side chain.

Question 43

Type of bond that joins amino acids

Answer 43

Peptide bond

Question 44

chains of amino acids, hundreds or thousands of amino acids.

Answer 44

polypeptides

Question 45

N terminus of polypeptide

Answer 45

α amino group

Question 46

C terminus of polypeptide

Answer 46

α carboxyl group

Question 47

types of bonds joining the side chains of insulin

Answer 47

disulfide bonds

Question 48

___________ breaks non-covalent bonds (denaturation).

Answer 48

Heating

Question 49

the sequence of amino acids in the polypeptide chain.

Answer 49

primary structure

Question 50

regular arrangement of amino acids within localized regions.

Answer 50

secondary structure

Question 51

Two common types of secondary structure:

Answer 51

α helix and β sheet.

Question 52

the folding of the polypeptide chain due to interactions between side chains of amino acids in different regions of the chain.

Answer 52

Tertiary structure

Question 53

the basic units of tertiary structure; are folded three-dimensional structures usually containing between 50-200 amino acids.

Answer 53

Domains

Question 54

interactions between different polypeptide chains in proteins composed of more than one polypeptide.

Answer 54

Quaternary structure

Question 55

catalysts that increase the rate of all chemical reactions in cells.

Answer 55

enzymes

Question 56

If an enzyme is present, the conversion is accelerated, but equilibrium is:

Answer 56

unaltered

Question 57

Enzymes are not ______ in chemical reactions

Answer 57

Consumed

Question 58

Energy required to reach the transition state (enzymes reduce this)

Answer 58

activation energy

Question 59

Enzymes must bind their substrates to form:

Answer 59

enzyme-substrate complex (ES).

Question 60

A substrate binds to a specific region of the enzyme called:

Answer 60

active site

Question 61

substrates bind by (3 things)

Answer 61

hydrogen bonds ionic bonds hydrophobic interactions

Question 62

conformation of both enzyme and substrate is modified.

Answer 62

induced fit

Question 63

digests bonds adjacent to hydrophobic amino acids

Answer 63

Chymotrypsin

Question 64

digests bonds next to basic amino acids

Answer 64

trypsin

Question 65

a nonprotein compound that is necessary for the functioning of an enzyme.

Answer 65

coenzyme

Question 66

Many coenzymes are closely related to ________, which contribute part or all of the structure of the coenzyme.

Answer 66

vitamins

Question 67

the product of a metabolic pathway inhibits an enzyme involved in its synthesis.

Answer 67

feedback inhibition

Question 68

Feedback inhibition is a type of __________ regulation

Answer 68

allosteric

Question 69

Phosphate groups are added to the side-chain OH groups of serine, threonine, or tyrosine residues.

Answer 69

phosphorylation