BIOL107 Lecture 7: Bio 107 Lecture 7 Eukaryotic Cells

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL107
• Professor: Martin Srayko

Document Summary

Dna in an unbound region called the nucleoid. Cytosol: the fluid portion of the cytoplasm. Organelle: any membrane bound structure in a eukaryotic cell. Most recent common eukaryotic ancestor probably arose 2. 1 billion years ago. Why did eukaryotes evolve membranous organelles: they may have first evolved a way to fold their membrane to increase the surface area of their cells. Mitochondria and chloroplasts arose in eukaryotes by endosymbiosis. A mutually beneficial relationship derived from once cell living inside another cell: ex. in the evolution of mitochondria: The engulfed bacterium received protection and nutrients. The anaerobic host cell first benefitted by housing a bacterium that could remove harmful o2. Eventually, as the relationship evolved, the internal (cid:862)prokaryote(cid:863) provided atp to the host evolution of the mitochondria. Mitochondria are descended from an ancient bacterium. Most closely related extant bacteria are the -proteobacteria (gram -: photosynthetic bacterium. Chloroplasts are descended from an ancient cyanobacterium.