.The human body is composed of organ systems. Which list represents a system organized from least to most complex?

Which of the following is not a main characteristic that scientists focus on when determining which kingdom an organism belongs to

Elephants in the savanna regions of africa dig holes in dried up river beds to reach water lying just below the surface. these holes provide drinking water for other animals as well. so, without the elephants, many animals might otherwise die from lack of water during the dry season. the location in which the elephants live is an example of a/n and the role they play in creating water holes is an example of a a) ecosystem; habitat b) community; niche c) habitat; niche d) niche; habitat

The cluster of developing cells from conception until birth is called an