1. 3.1: Biological Molecules
External Assessments:
AS – Paper 1 and Paper 2
A-level – Paper 1 and Paper 3
Internal Assessments:
1. Carbohydrates and lipids exam questions (due: )
2. Proteins and enzymes exam questions (due: )
3. DNA and RNA exam questions (due: )
4. End of topic test
Required Practicals:
1. Investigation into the effect of a named variable on the rate of an enzyme-controlled reaction
Comments:

2. 3.1.1: Monomers and Polymers
What is the difference between a monomer and a polymer?
How does a condensation reaction take place?
How does a hydrolysis reaction take place?
During which process/group of processes are polymers hydrolysed in the body into monomers?
Draw a diagram of the condensation and hydrolysis reactions between two α-glucose monomers.
Keywords:
Polymers, monomers, polymerisation, monosaccharaides, disaccharides, polysaccharides, soluble, insoluble, isomers, nucleotides, polynucleotide, amino acids, dipeptide, polypeptide, condensation, hydrolysis.
What is polymerisation?
What are isomers?
Draw a general structure of an amino acid, which is an example of a monomer.

3. 3.1.2: Carbohydrates Starch, glycogen and cellulose: Key words:
How are α-glucose monomers arranged to form the polymers of starch and glycogen?
How are β-glucose monomers arranged to form the polymer cellulose?
How do the molecular structure of starch, glycogen and cellulose relate to their function?
Key words:
starch; condensation reaction; osmosis; glycogen; cellulose; hydrogen bonds
Label the diagram to show the structure of starch:
List some of the properties of starch:
What is glycogen and what is it used for?
Draw a diagram to show the structure of cellulose:
Explain how its structure relates to its function:

4. 3.1.3: Lipids Triglycerides and Phospholipids
How are triglycerides formed?
Are triglycerides polymers?
How does the structure of a phospholipid differ from a triglyceride?
Keywords:
Triglycerides, Phospholipids, Saturated, Unsaturated, Hydrophobic, Hydrophilic, R-group, Emulsion test
Draw the basic structure of a triglyceride and label the parts.
Draw the basic structure of a phospholipid and label the parts.
What do the keywords below mean?
Hydrophilic:
Hydrophobic:
Which part of a phospholipid is hydrophilic and which is hydrophobic?
Describe the emulsion test, using diagrams.

5. Carbohydrates and Lipids Exam Questions (due: )
2. The diagram shows a triglyceride molecule.
Name part A.
……………………………………………………………….. (1)
(b) With reference to the named parts of the diagram, explain the difference between the terms:
Triglyceride and phospholipid;
……………………………………………………………………………………… ……………………………………………………… (2)
(ii) saturated and unsaturated.
Name the monosaccharides of which the following disaccharides are composed.
(i) Sucrose
Monosaccharides
………………………….and …………………………… (1)
(ii) Lactose
(b) Describe how you would use a biochemical test to show that a solution contained a non-reducing sugar, such as sucrose.
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………… (3)

6. 3.1.4.1: General Properties of Proteins
How are amino acids linked to for polypeptides – the primary structure of proteins?
How are polypeptides arranged to form the secondary structure and then the tertiary structure of a protein?
How is the quaternary structure of a protein formed?
How are proteins identified?
Key words: alpha-helix; amino acid; β-pleated sheet; biuret test; dipeptide; disulphide bonds; ionic bonds; hydrogen bonds; peptide bond; polymerisation; polypeptide; primary structure; protein; quaternary structure; secondary structure; tertiary structure;
Draw and label an amino acid:
Label the diagram to show the formation of a polypeptide bond:
What is the test for proteins and what results would you expect?

7. 3.1.4.1: General Properties of Proteins
How are amino acids linked to for polypeptides – the primary structure of proteins?
How are polypeptides arranged to form the secondary structure and then the tertiary structure of a protein?
How is the quaternary structure of a protein formed?
How are proteins identified?
Key words: alpha-helix; amino acid; β-pleated sheet; biuret test; dipeptide; disulphide bonds; ionic bonds; hydrogen bonds; peptide bond; polymerisation; polypeptide; primary structure; protein; quaternary structure; secondary structure; tertiary structure;
Draw the primary structure of a protein:
Draw the tertiary structure of a protein:
Draw the quaternary structure of a protein:
Draw the secondary structure of a protein:

8. 3.1.4.2: Enzymes Enzyme action Key words:
How do enzymes speed up chemical reactions?
How does the structure of enzyme molecules relate to their function?
What is the lock and key model of enzyme action?
What is the induced-fit model of enzyme action?
Key words:
activation energy; catalyst; enzyme; enzyme-substrate complex; induced fit; lock and key; substrate;
Draw a diagram to explain the lock and key model of enzyme action:
How does an enzyme’s structure relate to its function?
Draw a diagram to explain the induced-fit model of enzyme action:
Draw a sketch graph to show how enzymes speed up a reaction:

9. 3.1.4.2: Enzymes Key words: Factors affecting enzyme action
How is the rate of an enzyme-controlled reaction measured?
How does temperature affect the rate of an enzyme-controlled reaction?
How does pH affect the rate of enzyme-controlled reaction?
How does substrate concentration affect the rate of reaction?
Key words:
active site; denature; optimum; pH; substrate concentration; temperature
How does temperature affect the rate of an enzyme-controlled reaction?
How does pH affect the rate of an enzyme-controlled reaction?
How does substrate concentration affect the rate of an enzyme-controlled reaction?

10. 3.1.4.2: Enzymes Enzyme inhibition Key words:
How do competitive inhibitors and non-competitive inhibitors affect the active site?
What is enzyme inhibition?
Key words:
competitive inhibitor; end-product inhibitor; irreversible; reversible; non-competitive inhibitor
How do competitive inhibitors affect the active site? Use diagrams in your explanation.
How do non-competitive inhibitors affect the active site? Use diagrams in your explanation.

11. Proteins and Enzymes Exam Questions (due: )
2. The graph shows the effect of substrate concentration on the rate of an enzyme-controlled reaction.
(a) (i) Describe what the graph shows about the effect of substrate concentration on the rate of this enzyme-controlled reaction.
…………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………(2)
(ii) What limits the rate of this reaction between points A and B? Give the evidence from the graph for this.
1. A protein is formed from 300 amino acids. The diagrams show the primary, secondary and tertiary structures of this protein.
(i) Explain what causes the secondary structure to differ in length from the primary structure.
………………………………………………………………………………………………………………………………………………….(1)
(ii) Explain what is meant by the tertiary structure of a protein.
(iii) Heating may affect the tertiary structure of a protein. Explain how.
……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………....(2)

12. 3.1.5.1: Structure of DNA and RNA
What are the components of DNA?
How are these components arranged within the DNA double helix?
What is the function of DNA?
Key words: cytosine; thymine; adenine; guanine; phosphate; deoxyribose sugar; condensation reaction; mononucleotide; dinucleotide; polynucleotide; complementary; double helix; antiparallel; hydrogen bonds
Draw and label a nucleotide
List the four bases under the following columns:
Purines
Pyrimidines
Explain how DNA forms a double helix using the key words above:
Draw and label how two nucleotides condense to form the start of a polynucleotide strand
Explain how to the structure of DNA is linked to its function:

13. 3.1.5.1: Structure of DNA and RNA
Structure of RNA
What are the components of RNA?
How and where is RNA used in cells?
Key words:
adenine; thymine; guanine; cytosine; uracil; deoxyribose; ribose; rRNA; mRNA; tRNA
How is the structure of RNA different from that of DNA?
Name and explain 3 types of RNA and how they are important:

14. 3.1.5.2: DNA Replication Replication of DNA Key words:
What happens during DNA replication?
How is a new polynucleotide strand formed?
Why is the process of DNA replication called semi-conservation?
Key words:
nuclear division; cell division; DNA helicase; DNA polymerase, hydrogen bonds, nucleotides, complementary
Explain the semi conservative model of DNA replication
using the key words above:

15. : DNA Replication
Experimental Evidence for Semi-Conservative Replication
What happens during DNA replication?
How is a new polynucleotide strand formed?
Why is the process of DNA replication called semi-conservation?
Key words:
nuclear division; cell division; DNA helicase; DNA polymerase, hydrogen bonds, nucleotides, complementary
Explain the experimental evidence for semi conservative replication of DNA using the diagram below.

16. DNA and RNA Exam Questions (due: )
The diagram shows part of a DNA molecule.
DNA is a polymer. What is the evidence from the diagram that DNA is a polymer? (1)
Name the parts of the diagram labelled C, D and E.
Part C………………………………………….
Part D………………………………………….
Part E…………………………………… ...(3)
In a piece of DNA, 34% of the bases were thymine.
Complete the table to show the name and percentages of the other bases. (2)
Name of base
Percentage
Thymine 34

17. DNA and RNA Exam Questions (due: )
The diagram shows the bases in a rRNA molecule. In addition to A, U, C and G there are other bases present in tRNA. The other bases are shown by the letter D.
Which of the bases also occur in DNA? (1)
DNA and tRNA are both polynucleotide strands. Other than their nucleotide structure, give one similarity between the structures of DNA and tRNA (1)
Other than the difference in some of the bases, give three ways in which the structure of DNA is different from tRNA. (3) 1 2 3

18. DNA and RNA Exam Questions (due: )
Describe how DNA is replicated (6)
Total mark for DNA and RNA Exam Qs:
/17

19. Label the diagram of an ATP molecule:
What are the components of ATP?
How is ATP broken down?
How is ATP formed?
Key words: adenosine triphosphate; adenine; ribose; inorganic phosphate; ATP hydrolase; hydrolysis; phosphorylate; condensation; respiration.
Label the diagram of an ATP molecule:
Use a labelled diagram to explain the hydrolysis of ATP:
How is ATP resynthesised after hydrolysis?

20. 3.1.7: Water
Water is a major component of cells. It has several properties that are important in biology
Keywords: metabolite; hydrogen bonding; dipolar; specific heat capacity; latent heat of vaporisation; cohesion; surface temperature
Explain the role of water, with examples, in terms of:
Large latent heat of vaporisation:
Role as a metabolite:
Strong cohesion between the molecules:
Role as a solvent:
Has a high specific heat capacity: