Carbohydrates Important

Question 1

What are features of starch that make it act as a storage substance

Answer 1

It has a helical shape and is compact for easy storage

Insoluble in water and doesn’t affect the cell’s water potential

Question 2

Where is the OH switched on alpha glucose?

Answer 2

2 away from the oxygen

Question 3

Where is the OH group on a beta glucose

Answer 3

One away from the oxygen atom

Question 4

What term is used to describe 2 atoms that have the same number of protons but different neutron numbers?

Answer 4

Isotopes

Question 5

What word is used to describe an atom that has lost or gained an electron

Answer 5

An ion

Question 6

What word is used to describe a molecule that has an uneven distribution of electrons

Answer 6

Polar

Question 7

Name the type of bond between the hydrogen atoms and the oxygen atom in one molecule of water?

Answer 7

Covalent bonds

Question 8

Name the type of bond that forms between different water molecules due to their uneven charge

Answer 8

Hydrogen bond

Question 9

What is a polymer?

Answer 9

A substance made up of repeating subunits

Question 10

List the elements found in all the carbohydrates

Answer 10

Carbon
Oxygen
Hydrogen

Question 11

Describe the test for a reducing sugar?

Answer 11

Benedictus test, add an equal volume of Benedicts reagent to the sample and boil it
A positive result would be a brick red (precipitate)

Question 12

What is a pentose sugar?

Answer 12

A sugar with 5 carbon atoms

Question 13

What is lactose made up of?

Answer 13

Glucose, galactose

Question 14

What Is sucrose made up of?

Answer 14

Glucose, fructose

Question 15

Name the bond that forms between monosaccharides to produce a disaccharide or polysaccharide?

Answer 15

Glycosidic bond

Question 16

Name a polysaccharide commonly found in animals?

Answer 16

Glycogen

Question 17

Describe the test for starch

Answer 17

Add two drops of iodine to the sample if there is a colour change of the iodine from orange to blue black

Question 18

What is the function of cellulose

Answer 18

To help support the cell’s structure in the cell

Question 19

Name the monosaccharide that builds up cellulose?

Answer 19

Beta glucose

Question 20

What is condensation?

Answer 20

A reaction where two monomers are joined and water is a byproduct of that

Question 21

What is a hydrolysis reaction?

Answer 21

Where a polymer is separated into two monomers using water

Question 22

What is metabolism

Answer 22

All the chemical process that take place in living organisms are collectively called metabolism

Question 23

What is a molar solution

Answer 23

It’s a solution that contains one mole of solute in each litre of solution

Question 24

What are neutrons

Answer 24

Occur in the nucleus of an atom and have the same mass as protons but no electrical charge

Question 25

What are protons

Answer 25

Occur in the nucleus of an atom and have the same mass as neutrons but have a positive charge

Question 26

What are electrons

Answer 26

Orbit in shells around the nucleus but a long way from it They have such a small mass that their contribution to the overall mass of the atom is negligible . They are however negatively charged and their number determines the chemical properties of an atom

Question 27

How does an atom become an ion?

Answer 27

By losing or gaining electrons

Question 28

What are monosaccharides?

Answer 28

Monosaccharides are sweet tasting soluble substances that have the general formula (CH2O)n where n can be any number from 3 to 7

Question 29

What is Benedicts test?

Answer 29

Semi quantitative

Question 30

What is a glycosidic bond

Answer 30

The bond formed between molecules (monomers) during a condensation reaction

Question 31

What is starch

Answer 31

A polysaccharide found in many parts of a plant. | Made up of chains of alpha glucose monosaccharides liked by glycosidic bonds that are formed by condensation reactions.

Question 32

What are unbranched chains of starch made into ?

Answer 32

Tight coils that are very compact

Question 33

What are branched chains of starch

Answer 33

Not coiled

Question 34

What are some fun facts about starch ?

Answer 34

It is insoluble so it doesn’t affect the cell’s water potential It’s large so it doesn’t diffuse out of cells It’s compact so a lot of it can be stored in a small space When hydrolysed it forms alpha glucose which can be easily transported The branched form has many ends, each of which can be acted on by enzymes simultaneously meaning that glucose monomers are released very rapidly.