BIOLOGY:SUGARS [TOPIC 1:BIOLOGICAL MOLECULES] (3.1.2)

Question 1

What are sugars?

Answer 1

General term for monosaccharides and disaccharides.

Question 2

What are monosaccharides?

Answer 2

simplest sugars
building blocks of carbohydrates

Question 3

Which elements are always found in carbohydrates?

Answer 3

carbon
hydrogen
oxygen

Question 4

Which monomers are carbohydrates made from?

Answer 4

monosaccharides

Question 5

What are examples of monosaccharides?

Answer 5

glucose
fructose
galactose

Question 6

What is a hexose sugar?

Answer 6

A monosaccharide with 6 carbon atoms in each molecule

Question 6

What is glucose?

Answer 6

A hexose sugar

Question 7

How many types of glucose are there?

Answer 7

2
Alpha (a) and Beta (β)

Question 8

What are the alpha and beta glucose?

Answer 8

isomers

Question 9

Draw a molecule of a-glucose

Answer 9

check textbook

Question 10

What are isomers?

Answer 10

molecules with the same molecular formula as each other, but with the atoms connected in a different way

Question 11

Draw a molecule of β glucose

Answer 11

check textbook

Question 12

How are disaccharides formed?

Answer 12

When two monosaccharides join together

Question 13

What reaction occurs to create a disaccharide?

Answer 13

a condensation reaction between monosaccharides

Question 14

What bond is created when 2 monosaccharides join?

Answer 14

A glycosidic bond
A molecule of water is also released

Question 15

How is maltose created?

Answer 15

condensation reaction between 2 a glucose monosaccharides forming a glycosidic bond and a molecule of water

Question 16

What is sucrose?

Answer 16

A disaccharide

Question 17

What is sucrose formed from?

Answer 17

A condensation reaction between a glucose and fructose

Question 18

How do you remember how SUcrose is made?

Answer 18

Glucose (g for gun)
Fructose(f for fatma)

Question 19

What is Lactose?

Answer 19

A disaccharide

Question 20

What is Lactose formed from?

Answer 20

glucose
galactose

Question 21

How do you remember how lactose is formed?

Answer 21

LGG

Question 22

What is the test for sugars?

Answer 22

Benedict’s test

Question 23

What 2 categories can sugars be placed in?

Answer 23

reducing
non reducing

Question 24

What are examples of reducing sugars?

Answer 24

All monosaccharides some disaccharides eg. maltose and lactose

Question 25

How to test for reducing sugars?

Answer 25

Add benedicts reagent( which is blue) to a sample Heat in a water bath thats been bought to the boil

Question 26

How to tell if reducing sugars is present?

Answer 26

It will form a coloured precipitate

Question 27

What is a coloured precipitate?

Answer 27

solid particles suspended in the solution

Question 28

Why does the colour of the precipitate change if reducing sugars are present?

Answer 28

The higher the concentration of reducing sugar, the further the colour change. green-yellow-orange-brick red

Question 29

Whats are more accurate ways to compare amounts of reducing sugar in different solutions?

Answer 29

-use a colorimeter to measure the absorbance of the reaminign benedicts reagent -filter the solution and weigh the precipitate

Question 30

How to test for non reducing sugars?

Answer 30

First break them down into monosaccharides Get a new sample of the test solution(not same one you added benedicts solution to) Add dilute hydrochloric acid and carefully heating in water bath thats been bought to a boil Then nuetralise it by adding sodium hydrogencarbonate Finally carry out benedicts test how you do for reducing sugar

Question 31

Whats a example of a non reducing sugar?

Answer 31

Sucrose

Question 32

Draw the structure of galactose

Answer 32

Check textbook

Question 33

Draw structure of fructose

Answer 33

check textbook

Question 34

How do you remember where the OH group goes in alpha and beta glucose

Answer 34

1 carbon atom ABBA Alpha below Beta above