Describe two main sources of genetic variation.

Which of the following will not cause mass extinction? a. drastic change is weather b. geological change c. both a and b d. none of the above

The negative change found inside the plasma membrane is created by potassium ions sodium ions hydrogen ions chlorine ions

Which are characteristics of flukes? check all that apply. a they are free living. b they are a type of flatworm. c they reproduce sexually. d they have eyespots. e they are segmented.