An area with unifying characteristic is called as a region. The region is a broad geographic area, which is differentiated from other because of the similar features. In a region one or more than one types vegetational climax might be present. It is the continuous and extensive part of the surface. The area in a region is indefinite.
Hence, the given blank can be filled with region.
Answer:
Earth's atmosphere has a series of layers, each with its own specific traits. Moving upward from ground level, these layers are called the troposphere, stratosphere, mesosphere, thermosphere, and exosphere. The exosphere gradually fades away into the realm of interplanetary space.
Explanation:
Layers of Earth's Atmosphere | Center for Science Educationhttps://scied.ucar.edu
Artificial active immunity. I'm a bio major, hope I helped :)
Pretty sure the answer is Mitosis