B1.1.1 - B1.1.4

Question 1

When does a covalent bond form?

Answer 1

A covalent bond forms when a pair of electrons are shared between two atoms.

Question 2

Why are electrons shared between atoms?

Answer 2

Electrons are shared between atoms to generate strong bonds within compounds.

Question 3

What is carbon present in?

Answer 3

-Lipids
-Proteins
-Nucleic acids
-Carbohydrates

Question 4

How many electrons does carbon have in its outer shell? What does this mean?

Answer 4

Carbon has 4 valence electrons, meaning it can form 4 covalent bonds.

Question 5

What can carbon bond to?

Answer 5

Carbon can bond to other carbon atoms, or other atoms such as hydrogen, nitrogen or oxygen.

Question 6

What is an example of carbon atoms arranging themselves to form molecules with long branched chains?

Answer 6

Glycogen.

Question 7

What is an example of carbon atoms arranging themselves to form long straight chain molecules?

Answer 7

Cellulose.

Question 8

What is an example of carbon atoms arranging themselves to form molecules containing cyclic single rings?

Answer 8

The pyrimidines (thymine, uracil and cytosine).

Question 9

What is an example of carbon atoms arranging themselves to form molecules with multiple rings?

Answer 9

Starches and purines (adenine and guanine).

Question 10

What allows carbon to form varied carbon compounds with different shapes and hence, different biological properties?

Answer 10

Carbon produces a tetrahedral structure allowing it to form varied carbon compounds which have different 3-D shapes and hence, different biological properties.

Question 11

How many bonds can carbon atoms form and what combination?

Answer 11

Carbon atoms can form up to four single covalent bonds or a combination of double and single bonds.

Question 12

What functional groups can carbon atoms form part of that give organic compounds their individual properties?

Answer 12

-Hydroxyl groups
-Carboxyl groups
-Amino groups
-Phosphate groups

Question 13

How can carbon compounds be large molecules?

Answer 13

Carbon compounds can be large molecules by being made from many small, repeating subunits.

Question 14

What are monomers?

Answer 14

Monomers are the smaller units from which larger molecules are made.

Question 15

What are polymers?

Answer 15

Polymers are molecules made from a large number of monomers joined together in a chain.

Question 16

What is the process by which monomers join to form polymers?

Answer 16

Polymerisation.

Question 17

What are macromolecules?

Answer 17

Macromolecules are very large molecules.

Question 18

Why can polymers be macromolecules but not all macromolecules are polymers?

Answer 18

Polymers must consist of many repeating subunits.

Question 19

How are macromolecules formed?

Answer 19

Macromolecules are formed during condensation reactions.

Question 20

What is a condensation reaction?

Answer 20

A condensation reaction occurs when molecules combine together, forming covalent bonds and resulting in polymers (polymerisation) or macromolecules.
-Water is removed as part of the reaction.

Question 21

What are examples of condensation reaction?

Answer 21

-Polysaccharides
-Polypeptides
-Nucleic acids

Question 22

How are polysaccharides formed?

Answer 22

Polysaccharides are formed when two hydroxyl groups on different monosaccharides interact to form a strong covalent bond called a glycosidic bond.

Question 23

How are polypeptides formed?

Answer 23

Polypeptides are formed by condensation reactions. Two amino acid monomers interact to form a strong covalent bond called a peptide bond.

Question 24

How are nucleic acids formed?

Answer 24

Separate nucleotides are joined together via condensation reactions to form a phosphodiester bond.

Question 25

Between what do the condensation reactions occur to form nucleic acids?

Answer 25

The condensation reactions occur between the phosphate group of one nucleotide and the pentose sugar of the next nucleotide.

Question 26

Why is it called a phosphodiester bond?

Answer 26

Because it consists of a phosphate group and two ester bonds.

Question 27

What happens to macromolecules in digestion?

Answer 27

In digestion, macromolecules are broken down into their monomers.

Question 28

What allows macromolecules to be broken down into their monomers?

Answer 28

A hydrolysis reaction.

Question 29

What is a hydrolysis reaction?

Answer 29

The hydrolysis of macromolecules is when covalent bonds are broken when water is added. The -O and -OH from water are used to form the functional groups of the products.

Question 30

What is the difference between a condensation and hydrolysis reaction?

Answer 30

A condensation reaction is when water is removed whereas a hydrolysis reaction is when water is added.

Question 31

What are examples of hydrolysis reactions?

Answer 31

-hydrolysis of glycosidic bonds in poly- or disaccharides to produce monosaccharides.
-hydrolysis of peptide bonds in polypeptides to produce amino acids.
-hydrolysis of ester bonds in triglycerides to produce three fatty acids and glycerol.

Question 32

What are monosaccharides?

Answer 32

Monosaccharides are the monomers of carbohydrates.

Question 33

How to form a disaccharide?

Answer 33

By joining two monosaccharides.

Question 34

How to form a polysaccharide?

Answer 34

By joining many monosaccharides.

Question 35

How can monosaccharides join together and what is the new chemical bond between two monosaccharides called?

Answer 35

They can join together by condensation reactions. The new chemical bond that forms is known as a glycosidic bond.

Question 36

What are the properties of monosaccharides?

Answer 36

-Colourless crystalline molecules.
-Soluble in water.

Question 37

What is the most common monosaccharide?

Answer 37

Glucose.

Question 38

How does glucose aid in the production of ATP?

Answer 38

It is the main substrate used in respiration, releasing energy for the production of ATP.

Question 39

During what is glucose produced?

Answer 39

Photosynthesis.

Question 40

In what two structurally different forms does glucose exist as?

Answer 40

-Alpha glucose
-Beta glucose

Question 41

What does the structural variety between alpha and beta glucose result in?

Answer 41

It results in different functions between carbohydrates.

Question 42

What are the properties of glucose?

Answer 42

-Stable structure due to the presence of covalent bonds which are strong and hard to break
-Soluble in water due to its polar nature
-Easily transportable due to its water solubility
-A source of chemical energy when its covalent bonds are broken
-Oxidation of glucose provides large amounts of energy.