Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind that the trajectories of charged particles in both solar wind and magnetospheric plasma, mainly in the form of electrons and protons, precipitate them into the upper atmosphere (thermosphere/exosphere) due to Earth's magnetic field, where their energy is lost.
The resulting ionization and excitation of atmospheric constituents emits light of varying color and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of acceleration imparted to the precipitating particles. Precipitating protons generally produce optical emissions as incident hydrogen atoms after gaining electrons from the atmosphere. Proton auroras are usually observed at lower latitudes.
Some of the organisms have evolved in such a way that they remain inactive when the predator populations are active.
Adaptive theory of sleep suggests that the prey population prefer to sleep when (in this case, at night) the predators are most active. The prey population use this time in taking rest and restoring energy for other works. As the prey population is inactive and remained protected in safe places, they are less likely to be predated.
Hence, the correct answer is adaptive theory of sleeping.
Phagocytes are the type of cells that 'devour' foreign cells in order to protect the body using phagocytosis.
Answer:
Antibodies are made up of light chain and heavy chains. Heavy chain contains one variable region and three constant region while light chain have only one variable region and one constant region.
The variable region of the light chain and heavy chain of the antibody together makes the antigen-binding site called paratope which binds to their target antigen by non-covalent bond.
Epitope is the portion of an antigen that is recognized by the antibody and then the antibody binds to the epitope of antigen through its paratope region and helps in the killing of antigen.
Answer:
C. dams can help control floodwaters.
Explanation: