Mod 2 Topic 2

Question 1

• biological medium here on Earth
• most abundant substance in living systems
• making up 70% or more of the weight of most organisms

Answer 1

water

Question 2

Water has four emergent properties:

Answer 2

1. Cohesion and Adhesion of Water Molecules
2. Moderation of Temperature by Water
3. Evaporative Cooling of Water
4. Water as the Solvent of Life
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Question 3

• are macromolecules that exist as polymers called polynucleotides
• they store, transmit, and help express hereditary information

Answer 3

nucleic acid

Question 4

• a nucleotide is composed of three parts

Answer 4

a nitrogenous base, a five-carbon sugar, and one or more phosphate groups

Question 5

• has one six-membered ring of carbon and nitrogen atoms

Answer 5

pyrimidine

Question 6

members of
pyrimidine are

Answer 6

cytosine, thymine, and uracil

Question 7

• are larger, with a six-membered ring fused to a five-membered ring

Answer 7

adenine, and guanine

Question 8

_______, ________, _________are found in both DNA and RNA
__________ in DNA
__________ in RNA

Answer 8

Adenine, guanine, cytosine
Thymine (DNA)
Uracil (RNA)

Question 9

two sugar phosphate backbones run in arrangement called ________

Answer 9

antiparallel

Question 10

• a biologically functional molecule that consists of one
  or more polypeptides (polymers of amino acids), each folded and coiled into a specific three-dimensional structure

Answer 10

proteins

Question 11

roughly spherical proteins
shaped like long fibers

Answer 11

globular proteins
fibrous proteins

Question 12

folding of proteins are done by

Answer 12

chaperonins

Question 13

unravels and loses its native shape by a process called

Answer 13

denaturation

Question 14

it is a linked series of amino acids with a unique sequence

Answer 14

Primary structure

Question 15

This is collectively referred to as coils and folds, which are the result of hydrogen bonds between the repeating constituents of the polypeptide backbone

Answer 15

Secondary structure

Question 16

a delicate coil held together by hydrogen bonding between every fourth amino
acid

Answer 16

a- helix

Question 17

two or more strands of the polyopeptide chain lying side by side (called b strands) are connected by hydrogen bonds between parts of the two parallel polypeptide backbones

Answer 17

b pleated sheet

Question 18

It is the overall shape of a polypeptide resulting from interactions between the side chains (R groups) of the various amino acids

Answer 18

Tertiary structure

Question 19

caused by the exclusion of nonpolar substances by the
water molecules

Answer 19

Hydrophobic interaction

Question 20

_____________ are between polar side chains and ____________ are between positively and negatively charged side chains

Answer 20

Hydrogen and ionic bonds

Question 21

are formed when two cysteine monomers which have sulfhydryl groups (-SH) on their side chains are brought closer together by the folding of protein

Answer 21

Disulfide bridges

Question 22

It is the overall protein structure that results from the
aggregation of these polypeptide subunits

Answer 22

Quaternary structure

Question 23

Proteins function as

Answer 23

enzymes
storage of amino acids
coordinator of an organism’s activities
movement
protection against disease
transport of substances
response of cell to a chemical stimuli
support

Question 24

• are the one class of biomolecules that does not include true polymers, and they
  are generally not big enough to be considered as macromolecules
• They are grouped together
  because they mixed poorly with water

Answer 24

Lipids

Question 25

These are not polymers but are large molecules assembled from smaller molecules by dehydration reaction

Answer 25

Fats

Question 26

A fat is constructed from two kinds of smaller molecules:

Answer 26

glycerol and fatty acids

Question 27

an alcohol; each of its three carbons bear a hydroxyl group

Answer 27

Glycerol

Question 28

has a long carbon skeleton, having a carbon at one end which is a part of the carboxyl group

Answer 28

fatty acid

Question 29

These are formed if there are no double bonds between carbon atoms composing a chain, then as many hydrogen atoms as possible are bonded to the carbon skeleton.

Answer 29

Saturated fatty acid

Question 30

It has one or more double bonds , with one fewer hydrogen atom on each double-bonded carbon. Its double bonds are cis which has kinks to prevent the molecules from packing together closely enough to solidify at room temperature

Answer 30

Unsaturated fatty acid

Question 31

is similar to a fat molecule but has only two fatty acids attached to glycerol rather than three. The two ends of phospholipids show different behavior toward water.

Answer 31

Phospholipids

Question 32

When phospholipids are added to water, they self-assemble into double-layered structures called

Answer 32

bilayers

Question 33

These are lipids characterized by a carbon skeleton consisting of four fused rings. Different steroids are distinguished by the chemical groups attached to the rings

Answer 33

Steroids

Question 34

a steroid, is a crucial molecule in animals since it is a component of animal cell membranes and is also the precursor from which other steroids are synthesized, such as the sex hormones

Answer 34

Cholesterol

Question 35

include both sugars and polymers of sugars

Answer 35

Carbohydrates

Question 36

the monomers from which more complex carbohydrates are constructed

Answer 36

monosaccharides, or simple sugars

Question 37

double sugars, consisting of two monosaccharides joined by a covalent bond

Answer 37

Disaccharides

Question 38

polymers composed of many sugar building blocks

Answer 38

polysaccharides

Question 39

these are simple sugars which generally have formulas that are some multiple of the unit CH2O

Answer 39

Monosaccharides

Question 40

the most common monosaccharide, is of central importance in the chemistry of life

Answer 40

Glucose (C6H12O6)

Question 41

consists of two monosaccharides joined by a glycosidic linkage, a covalent bond formed by a dehydration reaction

Answer 41

Disaccharides

Question 42

are macromolecules, polymers with a few thousand monosaccharides joined by linkages

Answer 42

Polysaccharides