Pregunta 1
Pregunta
What is done in pairwise alignment?
Respuesta
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Two sequences are stuck on top of each others and the common areas lined up
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Two sequences are aligned from the beginning and their similarity analysed
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Two sequences are aligned and their similarity analysed
Pregunta 2
Pregunta
Local alignment assigns correspondences to all residues in the sequence, leaving gaps if necessary
Pregunta 3
Pregunta
The image shows which of the following?
Pregunta 4
Pregunta
The image shows a mismatch
Pregunta 5
Pregunta
What can sequence identity be used for?
Respuesta
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DNA sequence
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Amino acid sequence
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Gene sequence
Pregunta 6
Pregunta
Sequence identity can be how specific?
Pregunta 7
Respuesta
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Spaces in part of the sequence that allows other areas to align better
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Areas with a high density of indels
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Proteins that align when sequences are swapped over
Pregunta 8
Pregunta
What is the scoring system that determines an optimal alignment?
Respuesta
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+2 Match -1 Indel -2 Mismatch
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+2 Mismatch -1 Match -2 Indel
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+2 Match -1 Mismatch -2 Indel
Pregunta 9
Pregunta
Needleman and Wunsch algorithms find the highest scoring path across a matrix
Pregunta 10
Pregunta
Which is the light grey, and which is the dark grey?
Pregunta 11
Pregunta
PAM matrices used varies depending on the S.I
Pregunta 12
Pregunta
PAM250 scoring is used for remote homologues
Pregunta 13
Pregunta
In PAM250 scoring, scores are given based on what?
Pregunta 14
Pregunta
What does BLAST stand for?
Respuesta
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Basic Loci Alignment Search Tools
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Basic Loci Alignment Sequencing Tools
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Basic Local Alignment Search Tools
Pregunta 15
Pregunta
What is different about BLAST techniques?
Respuesta
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The compare residue 'words' instead of single residues/bases
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They work in areas of less than 50bp long
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They cover the whole genome very rapdily
Pregunta 16
Pregunta
A 'word' is 3bp or 11 aa long
Pregunta 17
Pregunta
Once the words have been found in the sequence, they are compared to the database- why?
Pregunta 18
Pregunta
An E value is expectation, not probability
Pregunta 19
Pregunta
What is the range and significance for the E value?
Smaller values are more likely
Pregunta 20
Pregunta
The E value is the probability of getting a result by change in a database of this size
Pregunta 21
Pregunta
What is the difference between P and E values
Respuesta
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Both are values for 'What is the probability of getting this result by chance alone?', but P accounts for database size
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Both are values for 'What is the probability of getting this result by chance alone?', E accounts for database size
Pregunta 22
Pregunta
In P values, <0.05 is significant
Pregunta 23
Pregunta
P value relies on a normal distribution
Pregunta 24
Pregunta
What are the limits of P?
Pregunta 25
Pregunta
An E of 4 is equal to - in a database of this size, I could get 4 matches by chance alone