1. Unit 2 – The Cell n Chapter 7, II ~ A Tour of the Cell

2. Other membranous organelles, I n Mitochondria quantity in cell correlated with metabolic activity; cellular respiration; double membranous (phospholipid); cristae/matrix; intermembrane space; contain own DNA

3. Other membranous organelles, II n Chloroplast type of plastid; double membranous; thylakoids (flattened disks); grana (stacked thylakoids); stroma; own DNA

4. Peroxisomes n Single membrane n Produce hydrogen peroxide in cells n Metabolism of fatty acids; detoxification of alcohol (liver) n Hydrogen peroxide then converted to water

5. The Cytoskeleton n Fibrous network in cytoplasm n Support, cell motility, biochemical regulation n Microtubules: thickest; tubulin protein; shape, support, transport, chromosome separation n Microfilaments : thinnest; actin protein filaments; motility, cell division, shape n Intermediate filaments: middle diameter; keratin; shape, nucleus anchorage

6. Centrosomes/centrioles n Centrosome: region near nucleus n Centrioles: 9 sets of triplet microtubules in a ring; used in cell replication; only in animal cells

7. Cilia/flagella n Locomotive appendages n Ultrastructure: “9+2” 9 doublets of microtubules in a ring 2 single microtubules in center connected by radial spokes anchored by basal body dynein protein

8. Cell surfaces & junctions n Cell wall: not in animal cells protection, shape, regulation n Plant cell: primary cell wall produced first middle lamella of pectin (polysaccharide); holds cells together some plants, a secondary cell wall; strong durable matrix; wood (between plasma membrane and primary wall)

9. Extracellular matrix (ECM) n Glycoproteins: proteins covalently bonded to carbohydrate n Collagen (50% of protein in human body) embedded in proteoglycan (another glycoprotein-95% carbohydrate) n Fibronectins bind to receptor proteins in plasma membrane called integrins (cell communication?)

10. Intracellular junctions n PLANTS: n Plasmodesmata: cell wall perforations; water and solute passage in plants n ANIMALS: n Tight junctions~ fusion of neighboring cells; prevents leakage between cells n Desmosomes~ riveted, anchoring junction; strong sheets of cells n Gap junctions~ cytoplasmic channels; allows passage of materials or current between cells