Esters are named as follow,
First the group which has replaced the Hydrogen atom of hydroxyl group of carboxylic acid is named. Like in In Phenyl propionate, Phenyl is written first as it is substituting -H of Propionic acid. Secondly the name of carboxylic acid is written with replacing the end
-ic acid with
-ate. Like -ic acid in propionic acid is replace by -ate i.e propionate.
Second example is also named according to above mentioned rules.
A. Earth's magnetic field reverses over time; the changes show that seafloor spreading has taken place over time.
Explanation:
The pattern of the magnetic minerals in seafloor ridges are aligned in a repeating pattern because the earth's magnetic field reverses overtime.
This provides evidence because the changes shows that the sea floor spreading has taken place over time.
- The concept of sea floor spreading was first suggested by Harry Hess in the early 1960's.
- Using sophisticated tools, he was able to discover stripe patterns of magnetic minerals in rocks.
- The earth can be likened to a giant bar magnet
- The geomagnetic field originates from the core where the movement of molten metals induces magnetism.
- In a fresh cooling magma, the metallic minerals are able to align their domains with the prevailing magnetic field.
- At some point the magnetic field is normal with a very strong intensity. At other times the intensity is low and it reverses.
- The minerals keeps track of the changes.
- This leads to striped pattern that has been used to suggest sea floor spreading.
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Sea floor spreading brainly.com/question/9912731
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Answer:
True
Explanation:
B cells are involved in the humoral immune response and T cells are involved in the cell-mediated immune response. Class 1 MHC molecules are found on all uncleared cells and class 2 MHC molecules are found on macrophages, B cells, and activated T cells.
