Answer:
I feel it's to easily differentiate the positive from the negative...... like in gram staining of bacteria, the colour tell us which bacteria is gram positive or gram negative...... I just feel that this is science and it is advisable to know what the opposite result of an experiment should look like.
About the geologic time scale divisions
The geologic history of the Earth is broken up into hierarchical chunks of time. From largest to smallest, this hierarchy includes eons, eras, periods, epochs, and ages.
Lipid bilayer model was proposed for its structure but it was modified and new structure is according to fluid mosaic model. Plasma membrane is selectively permible as it selects small molecules like lipid etc (composition is also of lipid and as solubility principle like dissolve like) so large and charged molecules like plasma and ion can't pass through it. Lipid are in form of layer so at the chain when ever other phosphate group attach the place conjugate molecule (phospholipid ) formed
Answer:
I hope this answers your question. Some people can't get certain vaccines when they are certain ages. If you are too young(just born) or too old, you may not want to have vaccines that can be hard on your body. People with certain health risks shouldn't get vaccines either. Another example would be someone has a severe reaction to a vaccination, they shouldn't get a booster for the vaccine in the future.
Explanation:
The ozone layer is a protective gas around the earth which protects the planet and all the living things on it :-)
