During speciation, when do two groups become recognized as separate species? A. when they look different. B. When they are separated by an isolation barrier. C. When they cannot interbreed. D. When they are both herbivores.

Which radiometric probe is appropriate to measure the age of the igneous rock

What kind of limited factor is parasitism considered

Scientist classify animals and sort them into groups, vertebrate and invertebrate. How do scientists classify humans? A) Scientists classify humans as vascular and as mammals. B) Scientists classify humans as vertebrates and as mammals.

Which of the following structures is made up mostly of water

A 23-year-old white woman has come to the clinic because she has missed two menstrual periods. she states that her breasts have enlarged and that her nipples have turned a darker color. your further response to this finding is to:

List three cash crops the europeans wanted the native americans and africans to yield

Which of the following is an example of a structural adaptation? A a wolf's howl B an insect's coloring C a fish's fin D a squirrel storing acorns

For your organ system, describe how the system works at the organ level

One step in a single eukaryotic cell becoming two daughter cells is the process of

What is the correct term that describes the tendency of a plant to grow towards light