genome projects

Question 1

projects to determine the entire DNA nucleotide base sequence of a wide range of organisms including humans, have taken place over the past few decades. The idea has been to map the DNA base sequences that make up the genes of an organism and then to

Answer 1

map these genes on the individual chromosomes on the individual chromosomes of that organism. In this way, a complete map of all the genetic material in an organism, the genome, is obtained

Question 2

the human genome consists of over 3 million base pairs organised into about 20,000 genes; sequencing every one of these bases is a HUGE task yet only took 13 years to complete- this would have been impossible without the use of

Answer 2

bioinformatics

Question 3

what is bioinformatics?

Answer 3

science of collecting and analysing complex biological data such as genetic codes

Question 4

bioinformatics uses computers to read, store and biological data at a much faster rate then previously- it also uses algorithms to analyse and interpret biological data. What are algorithms?

Answer 4

mathematical formulae

Question 5

regarding DNA sequencing, determining the entire DNA base sequence of an organism uses the technique of

Answer 5

whole-genome shotgun (WGS) sequencing

Question 6

what does whole-genome shotgun sequencing involve?

Answer 6

• involves researchers cutting the DNA into many small, easily sequenced sections and then using computer algorithms to align overlapping sections to assemble the enitre genome

Question 7

genome sequencing requires DNA sequencing but

Answer 7

on a much larger scale so slightly different methods need to be adopted

Question 8

of greater practical importance to humans, is not the genes themselves, but the proteins that these genes code for; these proteins are known as

Answer 8

the proteome

Question 9

define proteome

Answer 9

all the proteins produced in a given type of cell or organism ( the complete proteome) AT A GIVEN TIME under specific conditions

Question 10

why is the time element important in the proteome definition?

Answer 10

as a protein is only expressed when a gene is turned on so can vary

Question 11

why is determining the proteome of prokaryotic organisms like bacteria relatively easy because:

Answer 11

1- the vast majority of prokaryotes have just one, circular piece of DNA that is not associated with histones
2- no non-coding portions of DNA which are typical of eukaryotic cells

Question 12

knowledge of the proteome of organisms like bacteria has a number of applications:

Answer 12

• identification of those proteins that act as antigens on the surfaces of human pathogens; these antigens can be used vaccines against the diseases caused by these pathogens
• in the case of vaccines, the antigens can be manufactured and administered to people in appropriate doses
• in response to the antigen, memory cells are produced which trigger a secondary response when the antigen is encountered on a second occasion

Question 13

what is the problem of dtermining the proteome of more complex organisms?

Answer 13

• translating the knowledge of the genome into the proteome
• this is because the genome of complex organisms contains many non-coding genes
• in humans it is thought that less than 2% of our genes code for proteins