Year 12 Prework Booklet – Nucleic Acids

TASK 1 – KNOWLEDGE RECAP

Watch the following short videohttps://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/dna-structure-triple/

Then go to the following website and use it (and the video) to complete the questions belowhttps://www.bbc.co.uk/bitesize/guides/zys2v9q/revision/1

1. Define the term genome. Where in a eukaryotic cell is the genome found?

2. What does DNA stand for?

3. DNA is a polymer. Define the term polymer and name the monomers that make up DNA.

4. How many strands of DNA make up a molecule of DNA and what is the name given to the twisted spiral structure that it forms.

5. Define the term genetic code.

6. A gene is a small length of DNA. What does a gene code for?

7. Most DNA (98.5%) does not code for proteins. What is it used for?

8. Approximately how many genes are found in the human genome?

9. State three reasons why it is important to study the human genome.

Year 12 Prework Booklet – Nucleic Acids

10.Define the following terms:a. Allele

b. Genotype

c. Phenotype

11. Complete the following equation:

12. Individuals in a population are usually similar to each other, but not identical. Some of the variation within a species is genetic, some variation is environmental, and some is a combination of both.

a. State three examples of variation in humans that is due to genetics.

b. State three examples of variation in organisms that is due to their environment.

13.Tall parents will pass on “tall” alleles to their children. State an environmental factor that may result in these children with “tall alleles” having a short height.

14.Label the diagram below to show the three components of a DNA nucleotide

Year 12 Prework Booklet – Nucleic Acids

15.Give the full names of the bases that can be found in a DNA nucleotide.

NOTE: AT A LEVEL WE WILL ALWAYS STATE A NITROGEN CONTAINING BASE NOT JUST “BASE”

16.The diagram below shows the arrangement of the DNA nucleotides in a DNA molecule. The bases are found in the middle of the molecule and always pair up in the same way:

a. Adenine always pairs with ……………………….

b. Guanine always pairs with ……………………….

Add the letters of the bases on to the diagram below

17.What term is used to describe the pattern of base pairing?

18.There are weak bonds holding the base pairs together. What do you notice about the number of bonds between the different base pairs?

Year 12 Prework Booklet – Nucleic Acids

Then go to the following website to see how proteins are made from the code found in DNAhttps://www.bbc.co.uk/bitesize/guides/z3mbqhv/revision/5

19.Fill in the blanks below:…………………… are sections of the DNA. Each gene has the code for creating a specific …………………….. The sequence of ……………………………. in the gene controls which amino acids are joined in order to make a specific new protein (or enzyme) molecule. The proteins are then …………………. into their correct shape to make them ……………………..

20.The diagram below shows the relationship between the sequence DNA bases and the amino acids they code for.

a. How many DNA bases code for one amino acid?

b. What word, beginning with T, is given to these groups of DNA bases.

21.Complete the summary below:

Each …………………..of bases codes for …………….. particular amino acid. Amino acids are made in the ……………………. and ………………. dictated by the number and order of …………….. triplets.The amino acid molecules join together in a long chain to make a protein molecule. The …………………… and ………………….. of amino acids determines which protein is produced.

Watch the following video before continuing using the GCSE bitesize page to answer the following questions about protein synthesis

Year 12 Prework Booklet – Nucleic Acids

https://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/protein-synthesis-triple/

22.The DNA code is found in the nucleus. What is the name of the organelle where proteins are made?

23. What is the name given to the molecule which is a copy of the DNA code. It is made in the nucleus and moves to the cytoplasm.

24. What is the name of the carrier molecule that brings specific amino acids to the ribosome.

25. State the names given to the two stages of protein synthesis.26. Label the diagram below to show the main events that take place during the process of

transcription.

27.Fill in the blanks below to describe the process of transcription

Year 12 Prework Booklet – Nucleic Acids

28.Name two enzymes required for transcription.

29.Name the type of bonds found between complementary base pairs.

30.Name the 4 bases found in RNA.

31.What base is found in RNA but not in DNA?

32.Name the enzyme that breaks hydrogen bonds between complementary base pairs.

33.Name the enzyme that creates mRNA by joining RNA nucleotides together.

34.Complete the diagram below to show the process of translation

Year 12 Prework Booklet – Nucleic Acids

35.Fill in the blanks to describe the process of translation.

Year 12 Prework Booklet – Nucleic Acids

36. Name the cell structure to which mRNA attaches for the process of translation.

37.What name is given to the sequence of three mRNA bases that code for an amino acid?

38.What is the name given to the molecule that transports specific amino acids to the mRNA on the ribosome?

39. What molecule contains an anticodon?

40.Name the bond formed between adjacent amino acids.

Watch the following video

Year 12 Prework Booklet – Nucleic Acids

https://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/mutations-triple/

Click on the GCSE bitesize page to answer questions about DNA mutationshttps://www.bbc.co.uk/bitesize/guides/zys2v9q/revision/6

41.Define the term mutation.

42.Mutations occur continuously and randomly. State two factors that can increase the rate of mutations.

43.How can DNA mutations lead to an enzyme not working?

44. State two reasons why a DNA mutation may NOT result in a faulty protein being produced.

45.State three types of DNA mutation that may occur.

46.The diagram below shows three different ways a DNA sequence can be mutated. Write in the box to show what type of DNA mutation has occurred.

47. If a DNA mutation is to be passed on to an organism’s offspring. What type of cell must it occur in?

48.Why are not all DNA mutations bad?

Year 12 Prework Booklet – Nucleic Acids

TASK 2 – CHECK UNDERSTANDING – Complete WITHOUT using your notes

Year 12 Prework Booklet – Nucleic Acids

Year 12 Prework Booklet – Nucleic Acids

The diagram below shows part of a gene

Use the DNA wheel below to work out what amino acid is coded for by each DNA triplet and write in the box above. The first one has been done for you

Year 12 Prework Booklet – Nucleic Acids

Add the following labels on to the diagram below showing the process of protein synthesis

Translation Transcription DNA nucleus mRNA anticodon ribosome tRNA amino acid polypeptide

Year 12 Prework Booklet – Nucleic Acids

Then annotate your diagram with further details from your summary notes

Year 12 Prework Booklet – Nucleic Acids

Year 12 Prework Booklet – Nucleic Acids

GCSE mini YouTube lessons

If you are struggling with any of the topics then watch these 3-5 min YouTube lessons

https://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/dna-and-the-genome/

https://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/dna-structure-triple/

https://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/protein-synthesis-triple/

https://www.freesciencelessons.co.uk/gcse-biology-paper-2/inheritance-old/mutations-triple/

Stretch yourself – watch these short videos to introduce you to some Y12 content

https://www.youtube.com/watch?v=8m6hHRlKwxY&list=PLwL0Myd7Dk1HK8gH2XIafNgQJD1dMX2aW

https://www.youtube.com/watch?v=Qqe4thU-os8&list=PLwL0Myd7Dk1F1pp-DaLx3ygO_7xA-yyd4

https://www.youtube.com/watch?v=Qqe4thU-os8&list=PLwL0Myd7Dk1F0iQPGrjehze3eDpco1eVz&index=28