genome projects

genome

the complete set of genes in a cell of an organism

proteome

the full range of different proteins that a cell is able to produce at a given time

cellular proteome

protein produced by a cell

complete proteome

protein produced by an organism

what is the advantage of sequencing the genome of a simpler organism?

prokaryotes have a smaller genome so it’s quick to sequence

if their genome sequence is known, their proteome can easily be determined cuz they don’t have introns

so all DNA codes directly for proteins

what makes it difficult to determine the proteome of a more complex organism for its genome?

If their genome sequence is known, their proteome can’t be determined as easily because they have introns and regulatory genes (gene involved in controlling the expression of one or more other genes)

intron

non-coding region within a gene

whole genome shotgun sequencing

DNA is cut into small sections that are easy to sequence (using restriction endonuclease enzymes)

then use computer algorithms to align overlapping sequences into the whole genome

sequencing methods are continually updated

now all sequencing is automated

scientists can use protein structure to investigate the evolutionary relationships between different species. explain why.

1. the closer the amino acid sequence the closer the relationship

2. protein structure related to DNA base sequence

comparing the base sequence of genes provides more evolutionary information than comparing the structure of proteins. explain why.

1. longer base sequence than amino acid sequence

2. degenerate triplet code

3. introns

explain why restriction endonucleases only cut DNA at specific restriction sites

1. different lengths of DNA have different base sequences

2. results in different shape of active site

3. therefore specific sequence will only fit active site of enzyme

the gene machine

1. determine the amino acid sequence of required protein

2. determine the mRNA sequence of required protein

3. determine the DNA sequence of required protein

4. determine the required restriction endonuclease site and add to either side of gene sequence. can also add a promoter

suggest and explain how the viruses became able to infect other species of frog.

1. mutation in the genetic material
2. altered tertiary structure of the viral attachment protein
3. allows attachment protein to bind to receptors of other species

Name three techniques the scientists may have used when analysing viral DNA to determine that the viruses were closely related.

1. the polymerase chain reaction

2. genetic fingerprinting

3. gel electrophoresis

determining the genome of the viruses could allow scientists to develop a vaccine. Explain how.

1. the scientists could identify proteins that derive from the genetic code

2. they could then identify potential antigens to use in the vaccine