Molecular biology is a field of biology that looks at the molecular machinery of life. The field was founded in the early 1930s, though the phrase was only used in 1938 and the field didn't take off until the late 50s and early 60s. Since then, progress in the field has been massive.
The Ionosphere and the Exosphere (minor layers) are parts of the Thermosphere (major layer). The ionosphere is part of the theremosphere.
In the circle on the left, there is both a major arc and a minor arc. Look at the circle and try to figure out how you would divide it into a portion that is 'major' and a portion that is 'minor'. Identify the major and minor arcs in the circle below. minor arc; major arc ; In the circle on the left, there is both a major arc and a minor arc. Look at the circle and try to figure out how you would divide it into a portion that is 'major' and a portion that is 'minor'. Identify arcs