avg. prokaryotic gene & genome sizes

• 1 gene = 1000 bp
• genome = 5-10 Mb, 5,000-10,000 genes

avg. eukaryotic gene & genome sizes

• genes = 5-10 kb (genes are full of introns)
• genome = 30-3000 Mb, with 30,000-100,000 genes

transcriptones

• all transcripts produced in a cell 

proteome

• all proteins made in the cell 

metabolome

• all metabolic reactions in the cell, collectively

orthologs

• result from speciation
• genes are shared among species, nearly identical 
• same gene and same function, in two different species
• cannot have two orthologs in the same cell

paralogs

• result from gene duplication 
• one can be altered, while the other does it supposed job
• these look similar, but have different functions
• can have multiple paralogs in the same cell 

types of horizontal gene transfer

• transformation
• transduction
• conjugation 

pathogenicity islands

• give a pathogen characteristics that make it worse than other strains in some way
• cells become more pathogenic 

two signs of recent horizontal transfer

• GC base content (if one piece of DNA is 30% GC rich, while the rest of the genome is 50% GC rich, the 30% portion was recently transferred)
• Codon bias

codon bias

• 60 codons that encode 20 amino acids, but some species have particular codons that usually encode specific amino acids
• if a rarely used codon is chosen instead of a favored codon, this portion probably was recently transferred