Schließen
What are the main features of the genetic code?
Explain how the structure of an mRNA molecule differs from DNA
nucleotide
Give two ways in which the structure of a molecule of tRNA differs from the structure of a molecule of mRNA.
Draw the structure of DNA
Draw the structure of mrna
Draw the structure of mrna and dna and label the differences
draw the structure of trna
What is the role of RNA polymerase in transcription?
Describe the stages in transcription
Describe what happens during splicing
Describe what happens during translation
Describe the processes by which the sequence of subunits in DNA determines the mRNA and protein products in a cell.
Explain how the structure of DNA is related to its function.
What is a gene mutation?
How can mutations affect protein structure?
What is a silent mutation and how does it affect protein structure?
Starting from the base sequence of DNA, describe how a polypeptide is produced.
Explain how exposure to a mutagenic agent may result in an inactive enzyme being produced by a cell.
Explain why a mutation involving the deletion of a base may have a greater effect than one involving substitution of one base for another.
What are missense, nonsense and silent mutations? What happens when there are substitution, deletion and insertation mutations and what is a frameshift?
Explain how mutation of a gene can result in a strain lacking a particular enzyme.
This fungus is haploid. Suggest why mutant genes can be identified more easily in haploid fungi than in diploid ones.
Explain how a gene mutation may result in a different version of tyrosinase.
The faulty tyrosinase does not produce melanin.
Suggest an explanation for this.
Explain how the gene mutation results in failure to produce the enzyme phenylalanine hydroxylase.
A deletion mutation occurs in gene 1. Describe how a deletion mutation alters the structure of a gene.
Explain how genes control cell division and how gene mutation can lead to the formation of oncogenes
How do oncogenes affect cell division?
What are tumour suppressor genes and what happens if they mutate?
What happens when both proto-oncogenes and tumour suppressor genes are mutated? (use a car brake analogy to explain it)
How is mutation rate increase?
How does the degenerate code affect mutations?
Explain the roles of mRNA and molecule X (tRNA) in producing a particular type of protein.
Describe the similarities and differences between:
the structures of RNA and DNA
Describe the similarities and differences between:
the processes of replication and transcription.
Suggest why only about 1% of the genetic information is transcribed into functional RNA sequences in most mammalian cells.
