Genome Structure Flashcards
describe eukaryotic nuclear genomes
typically large, linear, and made of many separate chromosomes; large intergenic spaces and introns (only 1.5% of human genome is protein coding)
describe prokaryotic genomes
typically small (100,000 - 5 million bp), circular, often just a single chromosome; very compact, most of the genome encodes proteins, few intergenic spaces and no introns
why are prokaryotic genomes so small compared to ours?
vast majority of size difference is due to non-protein coding sequences (basically just promoters and protein coding sequences - no exons in bacteria)
why is gene regulation simpler in single-celled organisms versus multicellular organisms?
because they don’t have to make different types of cells
main reason for bacteria to regulate genes
to respond to their environment
what did chloroplasts and mitochondria evolve from?
symbiotic prokaryotes (bacteria)
mitochondria have their own ___. it looks similar to a _______.
genome; bacterial genome
describe our mitochondrial genome
circular, very tiny and compact, most genome encodes protein, few introns and intergenic sequences
mitochondrial genome bp in humans vs yeast, why is there a big difference?
17,000 bp in humans; 78,000 bp in yeast
eukaryotic cells provide a lot for the mitochondria (give food, break things down) so the mitochondria don’t need as much of the genome
describe the chloroplast genome
circular, not as small as mitochondrial genome, compact, few introns and intergenic regions
how many bp in a chloroplast genome?
100,000-200,000 bp
how many chloroplasts in a leaf cell?
100-10,000 chloroplasts
how many mitochondria are in an animal cell?
1,000-5,000 mitochondria
does yeast have a linear or circular genome?
eukaryote so linear
size (in bp) of human nuclear genome
3.2 billion bp
how many chromosomes do we have (haploid)?
23
size (in bp) of each chromosome
57-250 million bp
size (in protein coding genes) of each chromosome
200-2000 protein coding genes