Chapter 4: cells of the nervous system

Question 1

microtubules

Answer 1

• alpha and beta subunits arrange linearly

- develop and maintain neurons processes

Question 2

neurofilaments

Answer 2

• fibers that twist around each other
• bones of the cytoskeleton
• act as cross bridges for microtubules

Question 3

microfilaments

Answer 3

actin

• concentrated at cells periphery
• important for changing shape/growth of a neuron

Question 4

problem with mercury

Answer 4

-breaks down microtubules, mainly in developing brain

Question 5

protein synthesis

Answer 5

• occurs in cytoplasm
• DNA to mRNA in nucleus, mRNA leaves nucleus
• becomes associated with free or membrane bound ribosomes (proteins produced in RER are usually membrane bound proteins-ion channels, transporters)
• translation occurs
• creates string of amino acids, post-translation modifications occur to string, remove unwanted sections through enzymes

Question 6

Protein transport

Answer 6

• motor proteins
• axon is far from cell body
• proteins must be actively transported from golgi complex to terminal
• motor proteins do transporting (kinesin-pimp walk)
• anterograde transport=along microtubules, kinesin does anterograde
• retrograde transport= along microtubulues, from terminal bouton back to cell body. MAP-1C (dynein) does this