1. Endosymbiosis & Specialized Cells
9 Biology

2. Endosymbiosis Endosymbiotic Theory: Evidence:
Mitochondria and chloroplasts were thought to have been free- living prokaryotic cells
These structures were taken in by a eukaryotic cell, became useful to the cell metabolism and were retained as organelles
Evidence:
Both mitochondria and chloroplasts have:
70s ribosomes
Own DNA
Ability to reproduce independently from the cell
Double membrane on outside
Same size as prokaryotic cells

4. Specialized Cells: Animal cell examples: Plant Cell Examples:
Blood cells: anucleate, more room for hemoglobin thus more room for O2 molecules
Muscle cells: multinucleate, more mitochondria to produce more ATP needed for movement, have contractile fibers
Epithelial cells: skin cells modified to be a waterproof barrier for organisms
Plant Cell Examples:
Root cells: modified for absorbtion of water
Stem cells: modified to include vascular tissue to distribute water and glucose
Leaf cells: Extra chloroplasts for photosynthesis and storage areas for gas exchange with environment

5. Specialized Cell Examples