Answer;
Antibodies.
The human immune system fights infection by releasing antibodies.
Explanation;
The immune system acts to defend the body against pathogens such as viruses, bacteria and fungi that may cause a disease.
It does so using various types of mechanism, one is by the production of antibodies.
Antibodies are proteins that are produced by the B-cell and are used by the immune system to identify and neutralize pathogens.
These antibodies also activates proteins known as complements which assist in the killing of bacteria, viruses and the infected cells.
Three variables can be used .
1. Sun 2. Moon 3. Earth
These are suggestions that lizzie can control:
1.<span> Discover how long the Earth takes to orbit the Sun
2. how many hours it takes the Earth to spin around once on its own axis, 3. how long the Moon takes to orbit the Earth</span>
Geologists have divided the earth history into time units that are largely based on the earth's biotic composition. The modern geological time scale includes both relative and absolute age dating and represents the most up-to-date assessment of the earth's history.
In the modern geological time scale, the eras in earth's history when the planet was populated with advanced life forms are referred to as the Paleozoic (meaning ancient life), the Mesozoic (meaning middle life), and the Cenozoic (meaning recent life).
I'm pretty sure the answer is B. Invest in alternative energy sources that do not burn fossil fuels. The reason I would pick B is because in Antarctica the ice is melting more and more over time because, cars and factors etc are burning fuels which result in more damage to the ozone layer.
