1.3 — carbohydrates: monosaccharides and disaccharides

Question 1

what is another name for monosaccharides?

Answer 1

simple sugars

Question 2

monosaccharides are s______, s____-t______ and are found in many foods such as f_____, v_________ and g____. what are the missing terms?

Answer 2

soluble/sweet-tasting/fruits/vegetables/grains

Question 3

what is the general formula of monosaccharides and what range of numbers can ‘n’ be?

Answer 3

the general formula — (CH₂O)_n
the range of n — 3-7

Question 4

how are monosaccharides classified?

Answer 4

according to the number of carbon atoms in each molecule

Question 5

what is a hexose sugar?

Answer 5

a sugar with 6 carbon atoms

Question 6

what is a ribose sugar?

Answer 6

a sugar with 5 carbon atoms

Question 7

what are three examples of a hexose sugar?

Answer 7

glucose, fructose and galactose

Question 8

what are two examples of pentose sugars?

Answer 8

ribose and deoxyribose

Question 9

what is the formula of glucose?

Answer 9

C₆H₁₂O₆

Question 10

what are the two isomers of glucose?

Answer 10

alpha and beta

Question 11

what position is the hydroxyl group in alpha glucose?

Answer 11

at the bottom of the molecule

Question 12

what position is the hydroxyl group in beta glucose?

Answer 12

at the top of the molecule

Question 13

glucose is used as the _______ energy source in animals and plants. what is the missing term?

Answer 13

primary

Question 14

what two features of glucose help it function as an energy source?

Answer 14

1 . it is soluble — the hydroxyl groups can form hydrogen bonds with water, so it can be transported around organisms

2. its bonds store lots of energy — this energy is released when the bonds are broken

Question 15

when are disaccharides formed and by what bond?

Answer 15

when two monosaccharides join together though condensation reaction by a glycosidic bond

Question 16

what are three examples of disaccharides?

Answer 16

maltose, sucrose and lactose

Question 17

where is maltose found?

Answer 17

in grains and cereals

Question 18

what is sucrose used for?

Answer 18

a transport sugar in plants

Question 19

where is lactose?

Answer 19

in milk (as the main carbohydrate)

Question 20

what two monosaccharides form maltose?

Answer 20

2x alpha glucose

Question 21

what two monosaccharides form sucrose?

Answer 21

glucose x fructose

Question 22

what two monosaccharides form lactose?

Answer 22

glucose x galactose

Question 23

how are disaccharides formed?

Answer 23

condensation reactions between two monosaccharides

Question 24

how are disaccharides broken down?

Answer 24

hydrolysis reactions

Question 25

what is the covalent bond between disaccharides?

Answer 25

glycosidic bond

Question 26

how are 1,4 glycosidic bonds formed?

Answer 26

the OH group on carbon one reacting with the OH group on carbon four of another monosaccharide

Question 27

what happens when a water molecule is added to a disaccharide?

Answer 27

the 1,4 glycosidic bonds is broken to release the 2 monosaccharides

Question 28

how is glucose soluble and what is the outcome?

Answer 28

the hydroxyl groups can form hydrogen bonds with water, so it can be transported around organisms