Progenitor cells that divide to produce another progenitor cell and a migrating cell divide along a cleavage line that is _______ to the surface of the ________ zone

What term is used for the basic cells of the nervous system?

a) neurons b) glial cells c) myelin sheaths d) dendritic spines

If students who complete a study skills course raised their grade point averages, can we conclude that the course caused their improvement?

a. Yes, because the scientific data was collected. b. Yes, because a negative correlation exists between these students' grade point averages before and after taking the course. c. Yes, because the course resulted in a self-fulfilling prophecy. d. No, because there was no control group.