During an action potential, which of the following changes significantly? group of answer choices
a) the concentration gradients for na+ and k+.
b) the number of na+ and k+ ions crossing the cell membrane.
c) the membrane potential. the activity of the na+/k+ atpase.

If the birth rate of a population of dolphins is 2.0, the death rate is 0.5, and the population size is 100, what is this dolphin's population growth?

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area

Apaleontologist finds a plant fossil that shows that the plant had seeds. what can the paleontologist conclude?