dissachardies

Question 1

what are dissacharide?

Answer 1

carbohydrates containing 2 monosaccharides linked together

Question 2

what can disaccharides be?

Answer 2

the 2 component sugars may be the same or different

Question 3

what can a glycosidic bond involve

Answer 3

a glycosidic bond can also involve a nitrogen atom rather than an oxygen atom

Question 4

where is the glyosidic bonds present

Answer 4

is present between C1 of one sugar and an -OH group at any position on the other

Question 5

what type of reaction forms a glycosidic bond?

Answer 5

glycosidic bond formation is a condensation reaction

Question 6

what is sucrose made up of?

Answer 6

glucose+ fructose

Question 7

what is lactose made up of?

Answer 7

glucose+ galactose

Question 8

where is sucrose broken down?

Answer 8

broken down into monosaccharides in the stomach/intestine

Question 9

what is lactose also known as?

Answer 9

milk sugar

Question 10

how is lactose broken down?

Answer 10

hydrolysed by lactase in the small intestine

Question 11

what is maltose made up?

Answer 11

glucose and glucose

Question 12

summarise trehalose? (mycose)

Answer 12

two glucose molecules linked by an (1→1) bond
cryopreservative ability
used in food production (sweetener, stabilizer and thickener)
broken down by trehalase

Question 13

how else can you obtain dissachrides?

Answer 13

degradation of polysaccharides

Question 14

summarise maltose?

Answer 14

not a very common disaccharide

found in germinating grain

obtained by malting barley

formed by action of diastase on starch

Question 15

how is maltose formed?

Answer 15

formed by action of diastase on starch

Question 16

summarise cellobiose?

Answer 16

disaccharide subunit of cellulose, formed by partial hydrolysis
two glucose molecules linked by a β(1→4) bond
unlike maltose, can’t be digested by humans or fermented by yeast

Question 17

why is cellobiose different?

Answer 17

unlike maltose, can’t be digested by humans or fermented by yeast