Neurobiology E50 Midterm Review Questions 1a. What is the basis of the communicating syste m? 1b. How many estimated neurons and how many supporting (glial) cells does the brain contain? 1c. What are neurons specializ ed for? What is the basic term for this? a. Neuron b. 100 billion neurons & several times as many glial cells c. Elecltrical signaling over long distances btwn other neurons. Intercellular communication. 2a. What parts do neurons h ave that other cells of the body also have? 2b. What do you see when you stain neurons with Nissl substance and what do these stained parts do? What does this imply? 2c. What happens when y ou stain glial cells with Nissl? 2d. Are cytoskeletal elements proteins too? What do they do? a. Plasma membrane, nucleus, cytoplasm, and organelles b. A lot of ER, which is where proteins are made. Indicates neurons make lots of proteins c. They don't get stained as much d. Yes. They are neurofilaments that help keep appendages intact; scaffolding 3a. What do dendrites do and where do they arise from? 3b. What is the axon hillock? 3c. What kind of dendrites do most neurons have structurally? 3d. What dendrites the site of? What are they specialized for? 3e. What is the info car ried along the axon in the form of? Where does AP reach? 3f. Do all neurons have axons? How do they send info? a. They send and receive info from other neurons. Arise from neuronal cell body. b. Where AP are fired from. c. Multiple dendrites that are usually short and highly branched d. Site of contact with other nerve cells. Specialized for receiving info e. Self-regenerating electrical info called AP. Reaches end of axon, synaptic boutons. f. No. Transmit info locally. 4. What is a golgi stain? What part gets stained? stain is absorbed by very few neurons so not dendrite and cell body (black center). 5a. What are neuroglial cells? 5b. Ratio of glial to nerve cells? 5c. Do neuroglial cells participate directly in electrical signaling? 5d. What do glial cells do when brain injury results? a. Non-neuronal cells that have no axons. b. 3 to 1 c. no d. Brain injury results in loss of neural cells and thus, holes. Glial cells divide a lot and fill up the holes and repairs them with scar tissue. 6. What are the 4 functions of glial cells? 1) Maintain the ionic milieu of nerve cells by keeping important ions (K+, Na+, Ca2+, Mg+) at the right concentrations. 2) Modulate rate of nerve signal propagation by cover ing axon with lipid for better transmission 3)Modulate synaptic action by controlling NT uptake 4) Aiding in recovery from neural injury 7. What are the 3 types of glial cells in the CNS and outside? Astrocytes (no counterpart outside), Oligodendrocytes (Schwann Cells PNS), Microglial Cells (macrophages outside CNS) 8a. Function of astrocytes? 8b. Where are astrocytes restricted to? 8c. What can you stain with to show appendages of astrocytes? a) Provide approp chemical env for neuronal signaling, supports around neuron, and fills in holes in brain from injury (replaces damaged tissue with scar tissue). b) Restricted to brain & spinal cord. c) Glial fibrular protein 9a. Function of oligodendrocyte s? Equivalent in PNS? 9b. Do they have dendrites? a) form myelin around some axons. Schwann cells in PNS b) no