The adjustable ring of circular and radial muscles that controls the amount of light entering the eye is
the
a. lens.
b. cornea.
c. pupil.
d. iris.
e. retina.
D
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The embryonic skeleton of all vertebrates is made of:
a. yellow bone marrow b. elastic tissue c. loose connective tissue d. cartilage e. muscle tissue
The electrons that are passed to NADP+ at the end of the electron transfer chain were obtained from ____
a. water b. CO2 c. glucose d. sunlight e. ATP
Matching I. Even though there may be more than one
correct letter response to some numbered items, discriminate and “juggle” so that you have the one BEST response for each blank. 1. ___ effector 2. ___ excitatory postsynaptic potential 3. ___ ganglion 4. ___ integrator 5. ___ Inhibitory Postsynaptic Potential 6. ___ interneuron 7. ___ muscle spindle 8. ___ myelin sheath 9. ___ neuroglia 10. ___ receptor 11. ___ recovery period 12. ___ response 13. ___ sodium-potassium pump 14. ___ stimulus 15. ___ neurotransmitter molecule A. cells that nurture and support neurons B. a hyperpolarizing event C. a neuron cannot propagate an action potential at this time D. ACh or GABA E. interneuron in brain or spinal cord F. establishes basis of resting membrane potential G. sheathed muscle cells that contain receptors H. input I. integrator cell between sensory and motor J. modified dendrite of a sensory neuron K. a depolarizing event L. output M. muscle or gland N. produced by a Schwann cell O. cluster of cell bodies outside the CNS
The need for larger and more frequent doses of a drug is called
a. addiction. b. habituation. c. psychological dependence. d. synergism. e. tolerance.