GCU BIO 201 EXAM 3 2026
QUESTIONS AND ANSWERS| ACE
YOUR GRADES.
1. Fast twitch fibers - correct answer -muscle fibers that contract
rapidly and forcefully but fatigue quickly (few mitochondria,
large diameter)
2. Calmodulin - correct answer -A cyoplasmic Ca2+-binding
protein. Calmodulin is particularly important in smooth muscle
cells, where binding of Ca2+ allows calmodulin to activate
myosin light-chian kinase, the first step in smooth muscle cell
contraction.
3. Myosin light chain kinase - correct answer -enables myosin
heads to attach to actin
4. No - correct answer -does smooth muscle have sarcomeres?
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5. Phosphorylation - correct answer -The metabolic process of
introducing a phosphate group into an organic molecule.
6. Astrocytes - correct answer -contributes to and regulates Blood
Brain Barrier (BBB); regulates composition of fluid in the brain;
converts glucose to lactate for the brain to use as energy;
secretes chemicals that stimulate nerve maintenance
7. Microglia - correct answer -Act as phagocytes, eating damaged
cells and bacteria, act as the brains immune system
8. Oligodendrocytes - correct answer -Form myelin sheath in CNS
9. Ependymal cells - correct answer -produce and circulate
cerebrospinal fluid (ciliated for this movement)
10. Satellite cells - correct answer -protect neuron cell bodies
11. Schwann cells - correct answer -produce myelin in PNS
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12. Nissl bodies - correct answer -RER and free ribosomes that
make neurotransmitters
13. Initial segment of axon - correct answer -Area of the axon
having the lowest threshold for stimulation, so the action
potentials begin at this point
14. Axoplasm - correct answer -cytoplasm of axon
15. Axolemma - correct answer -plasma membrane of axon
16. Axon collaterals - correct answer -Side branches of the
axon, carry signal to other cells.
17. Axon telodendria - correct answer -branches on axon
terminal propagating signals towards post synaptic cell