BIOL 111 Lecture Notes - Lecture 4: Auxospore, Nuclear Membrane, Spindle Apparatus

• School: McGill University
• Department: Biology
• Course: BIOL 111
• Professor: Andrew Hendry

Document Summary

Relationship between genome size and gene number is weak -> c-value paradox". Prokaryotes have small genomes because each gene needs energy to be replicated (2% of energy budget) and each gene needs to be expressed (major cost and 75% of energy budget) Eukaryotes can transcend the limit and have larger genomes because oxidative metabolism is delegated to mitochondria. Food particle is held in phagosome (internal department), can fuse with lysosomes with enzymes, then digested and products diffuse into cytosol. Digesting food internally is more efficient and prevents free riders. If cells can survive in the predator, grow using nutrients in cytoplasm and attack, then it is intracellular parasite. If two cells, one inside the other, exchange nutrients -> endosymbiosis. Endosymbiont is more efficient bc division of labour. Has 2 membranes, suggests was probably independent bacterium; and its own genome, though many of its genes has been transferred to nucleus. Nuclear membrane permits fine control of transcription.