Check points throughout the cell cycle that determine when the cell should begin the next phase
The answer is "D"
The body's first line of defense is also known as Innate immunity and incudes mucous membranes. Both the intact skin and mucous membranes of the body offer a high degree of protection against pathogens.
A good example is the mucous membrane of the respiratory tract. It is lined up with cilia and covered with mucus. The coordinated beating of the cilia drives the mucus up to the nose and mouth where the trapped bacteria can be expelled.
(Lymph nodes and white blood cells belong to the second line of defense, not the first)
Tectonic plates float on amass of melted lava. its very hot and produces gases. these gases tend to move the plates with the compression becomes very high and the gases do not find an exit.the other reason is the plates themselves tend to move. because of the temprature gradient. the plates are hotter on the lower side which forces the plates to move up. and they are colder on the outside,which forces the plates to move downward..this is the other reason why the plates move