Carbohydrates (3)

Question 1

stereoisomers that are mirror images of
each other

Answer 1

enantiomers

Question 2

pairs of isomers that have opposite configurations at one or more chiral centers but are NOT mirror images

Answer 2

diastereomers

Question 3

Two sugars that differ in configuration at only one chiral center

Answer 3

epimers

Question 4

–most abundant hexose

Answer 4

D- glucose

Question 5

the building block of the disaccharides sucrose, lactose, and maltose, and polysaccharides such as amylose, cellulose, and glycogen.

Answer 5

D- glucose

Question 6

obtained as a hydrolysis product of the disaccharide lactose

Answer 6

D – galactose

Question 7

prevalent monosaccharide in the cellular membranes of the brain and nervous system, “brain sugar”

Answer 7

D – galactose

Question 8

sweetest of all carbohydrates

Answer 8

D – fructose

Question 9

obtained as a hydrolysis product of the disaccharide sucrose.

Answer 9

D – fructose

Question 10

• obtained from the hydrolysis of starch.
• the two glucose units are linked by an α – 1,4 – glycosidic bond.
• a reducing sugar because mutarotation occurs at the anomeric carbon to give an aldehyde group.
  (ALPHA - D glucopyranosyl-(1->4)ALPHA - D - glucopyranose)

Answer 10

Maltose

Question 11

– milk sugar
- consist of a β–1,4–glycosidic bond between β–D–galactose and β–D–glucose
- also a reducing sugar
(BETA-D-galactopyranosyl-(1->4)BETA-D-glucopyranose)

Answer 11

Lactose

Question 12

• table sugar
• consists of an α,β–1,2–glycosidic bond between C-1 of α-D–glucose and C-2 of
  β–D–fructose
• not a reducing sugar
  (ALPHA - D glucopyranosyl-BETA - D - fructofuranoside)

Answer 12

Sucrose

Question 13

– obtained by partial hydrolysis of cellulose
- the two glucose units are linked by a β–1,4–glycosidic bond
- also a reducing sugar
(BETA-D-glucopyranosyl-(1->4)BETA-D-glucopyranose)

Answer 13

Cellobiose

Question 14

Play a vital role in energy storage and in maintaining the structural integrity of an
organism.

Answer 14

Polysaccharides

Question 15

consist of only one type of monosaccharide repeating units

Answer 15

homopolysaccharides

Question 16

consist of two or more types of monosaccharides

Answer 16

heteropolysaccharides

Question 17

• the storage form of glucose in plants
• found as insoluble granules in rice, wheat, potatoes, beans, and cereals
• composed of two kinds of polysaccharides, amylose (20%) and amylopectin (80%)

Answer 17

Starch

Question 18

• animal starch; storage form of glucose in animals
• is a polymer of glucose that is stored in the liver and muscles of animals.
• The only difference from starch: the number
  of branches
  -α(1→6) branches every 8-12 residues

Answer 18

Glycogen

Question 19

• major structural material of plant cells
• most abundant polysaccharide or most abundant organic molecule in the world
• glucose molecules form a long unbranched chain similar to that of amylose but the glucose units are linked by β–1,4–glycosidic bonds.

Answer 19

Cellulose

Question 20

• structural polysaccharide of brown algae and kelp
• industrial uses are as a thickener, emulsifier, stabilizer, and hydrophilic agent in medical and cosmetic ointment bases

Answer 20

alginic acid

Question 21

• structural polysaccharide in red seaweeds
• used in the preparation of chocolate drinks to hold cocoa particles in suspension

Answer 21

carrageenan

Question 22

structural polysaccharide in insect skeletons and shells of crabs and lobsters and also in the cell walls of most fungi and many algae

Answer 22

chitin

Question 23

• not digestible by humans, including cellulose, hemicellulose, pectins, gums and lignins
• food sources include whole grains, bran, fruits, and vegetables
• aids in the formation of bulk in the intestinal tract, which increases the absorption of water along the tract; does not contribute to caloric intake; remove digestive wastes /carcinogens

Answer 23

Dietary Fibers

Question 24

• bonded to hydrophobic molecules, such as
  steroids, to increase their solubility in water.
• When bonded to the modified sugar, steroids are more readily removed from the body.

Answer 24

α–D–glucuronate

Question 25

thought to stimulate the production of collagen; helps repair eroded cartilage in arthritic joints

Answer 25

α–D–glucosamine

Question 26

a component of bacterial cell walls

Answer 26

α–D-N–acetylglucosamine

Question 27

is a component of the A, B, O blood group antigens

Answer 27

α–D-N–acetylgalactosamine

Question 28

- a polymer of D–glucuronic acid and D–glucosamine - an anticoagulant used in open heart surgery to prevent clotting of the blood

Answer 28

heparin

Question 29

- a polymer with alternating units of D–glucuronic acid and N–acetyl–D- glucosamine - present in connective tissues - abundant in the fluid of joints and in the vitreous humor of the eye which serves as lubricant & shock absorber.

Answer 29

hyaluronic acid

Question 30

- major structural components of cartilage, bone, cornea, and other connective tissue structures in vertebrates - consists of repeating units of D-glucuronic acid-2-sulfate-D-glucosamine sulfate.

Answer 30

chondroitin sulfate