Chem 40

Question 1

Carbohydrates

Answer 1

• Hydrates of carbon
• Main function is to provide
  energy
• most abundant biomolecules on Earth

Question 2

________ converts more than 100 billion metric tons of CO2 and
H2O into cellulose and other plant products

Answer 2

Photosynthesis

Question 3

a multistep process that forms carbon
dioxide, water, and a great deal of energy

Answer 3

oxidation of glucose

Question 4

Functions of Carbohydrates

Answer 4

• Storehouse of chemical energy.
• Supportive structural components of plants and some animals.
• Essential components of the genetic material
• Ligands and receptors in cellular communication

Question 5

Classes of Carbohydrates

Answer 5

• monosaccharides
• oligosacchraides
• Polysaccharides

Question 6

Monosaccharides

Answer 6

simple sugars, consist of a single polyhydroxy aldehyde or ketone unit. The most abundant monosaccharide in nature is the six-carbon sugar D-glucose

Question 7

Oligosaccharides

Answer 7

• consist of short chains of monosaccharide units joined by characteristic linkages called glycosidic bonds
• Disaccharides

Question 8

Polysaccharides

Answer 8

• sugar polymers containing more than 20 or so monosaccharide units, and some have hundreds or thousands of units
• Example: Cellulose

Question 9

have three to seven carbon atoms in a chain, with a carbonyl group at either the terminal carbon (C1) or the carbon adjacent to it (C2).

Answer 9

monosaccharides

Question 10

Monosaccharides are usually drawn _______ , with the carbonyl group at
the _____

Answer 10

vertically; top

Question 11

polar compounds with high melting points

Answer 11

monosaccharides

Question 12

What makes monosaccharides water soluble?

Answer 12

presence of so many polar functional groups capable of hydrogen
bonding

Question 13

Two families of monosaccharides

Answer 13

aldoses
ketoses

Question 14

[aldose or ketose] If the carbonyl group is at an end of the carbon chain of the monosaccharide

Answer 14

aldose

Question 15

[aldose or ketose] if the carbonyl group is at any other position of the
monosaccharide

Answer 15

ketose

Question 16

simplest aldehyde

Answer 16

glyceraldehyde

Question 17

simplest ketone

Answer 17

dihydroxyacetone

Question 18

monosaccharide with 3Cs, 4C’s, 5Cs, 6Cs

Answer 18

triose (3)
tetrose (4)
pentose (5)
hexose (6)

Question 19

[Stereoisomerism] Aldoses & ketoses
(except dihydroxyacetone) are

Answer 19

OPTICALLY ACTIVE

Question 20

[T or F] d and l refers to the direction in which plane polarized light is rotated

Answer 20

True

Question 21

[clockwise or counterclockwise] - D

Answer 21

clockwise

Question 22

[clockwise or counterclockwise] - L

Answer 22

counterclockwise

Question 23

Stereoisomers

Answer 23

isomers that differ in spatial arrangement of atoms, rather
than order of atomic connectivity

Question 24

Anomeric carbon

Answer 24

carbonyl carbon (C=O)

Question 25

Penultimate carbon

Answer 25

2nd to the last carbon

Question 26

number of possible stereoisomers of a monosaccharide _____ _____ with the number of ______ ______ present

Answer 26

increases exponentially; stereogenic centers