Ca2+ enters the cell when an action potential is generated. Diffusion and electrostatic pressures push Ca2+ into the cell. Ca2+ channels are:

Guan-yin is a Chinese immigrant. Before applying for college, she took the TOEFL, which a test of English proficiency. Scores on the TOEFL range from 310 to 677 . Guan-yin's score was 500, which is not quite good enough to gain college acceptance

Based on the findings of Johnson and Newport (1989), the youngest Guan-yin could have been when she came to the USA was ___ years old. a. seven b. ten c. fifteen d. twenty-two

The leading causes of U.S. deaths in middle age are __________ and __________

A) motor vehicle collisions; cancer B) falls; motor vehicle collisions C) cancer; cardiovascular disease D) falls; cardiovascular disease