Basics of molecular biology Flashcards
In what direction are DNA and RNA analysed?
They are analysed in the 5’ - 3’ direction
What do we mean by the reverse complement of a DNA sequence
That the order has been reversed, and the matching bases have been written.
e.g
ATT TTA (Reversed) AAT (Matching bases)
What bases pair together?
A with T,
C with G
How does DNA turn into RNA?
The strands are separated, then a protein matches to the DNA, creating the RNA
Where are RNA molecules processed?
In the ribosomes
How many bases on the RNA are needed to make an amino acid?
3
How is the protein structure determined?
It is determined by the amino acid sequence, and the interactions between those acids
Why are some genomes larger than others?
Genomes in plants are generally larger due to their inability to move to change their environment, so they have more genes ‘in reserve’ that can be activated to adapt to an environment.
Genomes in bacteria are generally smaller so that it can grow quickly
What does 2x=46 mean?
It means that that organism is diploid, and has 46 chromosomes in total.
What does diploid mean?
An organism that has two full sets of chromosomes, one from each parent
Does gene density differ from genome to genome?
Yes:
E.coli has 935 genes per Mbp,
H.Sapiens have 6.6 genes per Mbp
What is the scale of Base Pairs?
bp - single pair
kbp - kilo base pair (1,000 bp)
Mbp - Mega base pair (1,000,000 bp)
Gbp - Giga base pair (1,000,000,000 bp)
How often has the number of bases in each release of GenBank doubled since 1982?
Every 18 months
What is a SNP (Snip)?
What does it stand for
A Single Nucleotide Polymorphism
What does it mean if a snip is synonomous?
When they do not cause a change in amino acid
What does it mean if a snip is non-synonomous?
They cause a change in the amino acid produced
Where do non-synonymous snips have the largest impact?
In regulatory regions
What is Homologous Recombination?
The exchange of sequences between two similar or identical molecules of DNA
- It introduces variation in gametes
- Required for horizontal gene transfer
- Used for the repair of double strand breaks in DNA
What does CRISPR stand for?
Clustered Regularly Interspaced Short Palindromic Repeats
How does CRISPR work?
A synthetic protein enters a cell, this protein has a guide RNA in it.
It then cuts the DNA, providing a gap in the DNA
We can then either allow the DNA to naturally repair, or insert engineered DNA with homologous overlaps at the ends
