Unit 5: Genetic Expression Flashcards
1
Q
Role of RNA Polymerase in Transcription?
A
joins nucleotides 💗 to form a STRAND
2
Q
Which organelle involved in translation?
A
Ribosome
3
Q
Two types of mutations that can occur?
A
- SUBSTITUTION
* DELETION (causes FRAME SHIFT)
4
Q
Differences between mRNA and tRNA (4 marks)
A
- tRNA has HYDROGEN bonds between base pairs
- mRNA has NO binding sites for AMINO ACIDS
- mRNA LOOOONGER than tRNA
- mRNA is LINEAR but tRNA clover shaped ♣️
5
Q
give 3 factors which increases the frequency at which a mutation in DNA occurs:
A
- High energy radiation
- UV Light 💜🔦
- ❌ rays
6
Q
Which organelle does Transcription take place?
A
Nucleus
7
Q
What does mRNA consist of?
A
- RIBOSE sugar
* Phosphate
8
Q
Describe the role of tRNA in Translation: (3 marks)
A
- ANTIcodon complimentary 💗 to codon
- SPECIFIC amino acid
- is CARRIED to the ribosome
9
Q
why might a DELETION have a greater effect than a SUBSTITUTION? ((3))
A
- deletion causes FRAME ⬅️➡️ shift
- changes seq. of amino acids from point on MUTATION
- substitution alters ONE codon
- code degenerate; still codes for same amino acid
10
Q
Describe TRANSLATION (7 marks)
A
- mRNA leaves NUCLEUS through nuclear pores
- to Ribosome
- tRNA’s anticodon is complimentary 💗 to mRNA’s codon
- tRNA molecule brings specific amino acids to ribosome
- peptide bonds form between amino acids
- tRNA detaches and collects another Amino Acid
- ribosome moves along mRNA
11
Q
What is an oncogene?
A
1) mutated protooncogene
2) Rate of cell division out of control
12
Q
How does a tumour suppressor gene prevent/slow down formation of a tomour?
A
1) reduced cell division
