BIO130H1 Final: BIO130 Final Study Notes
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BIO130H1 Full Course Notes
Verified Note
31 documents
Document Summary
Definitions: cytoplasm: contents of cell outside nucleus; includes organelles, cytosol, cytosol: aqueous part of cytoplasm (no organelles, lumen: inside organelles. Cells separated from external world by thin, fragile structure called plasma membrane, 3-layered, darkly staining inner and outer layers and lightly staining middle layer. All membranes (plasma, nuclear, cytoplasmic; from plants, animals, microorganisms) show same ultrastructure. Cell membranes contain lipid bilayer, 2 dark-staining layers in electron micrographs correspond to inner and outer polar surfaces of bilayer. An overview of membrane functions: compartmentalization: continuous, unbroken sheets; enclose compartments. Pm encloses contents of cell, nuclear and cytoplasmic enclose intracellular spaces. Allows specialized activities to proceed without external interference, enables cellular activities to be regulated independently: scaffold for biochemical activities: distinct compartment themselves. Allows cell to accumulate substances (e. g. sugar, aas) to fuel metabolism, build macromolecules. Transport specific ions, establishing ionic gradients across membrane: responding to external stimuli: signal transduction. Receptors combine with specific molecules (ligands), respond to stimuli (e. g. light, mechanical tension)
