Answer:
The immune system protects the host from pathogenic organisms (bacteria, viruses, fungi, parasites). To deal with this array of threats, the immune system has evolved to include a myriad of specialised cell types, communicating molecules and functional responses.
Explanation:
Energy flows through an ecosystem and cannot be recycled.
Lavoisier would have taken mercury and heated it up to 350 degrees centigrade in air and then found that a new compound was formed a red or yellow mineral which would be mercury oxide so the experimental observation would be the change in color of the mercury and the formation of a mineral with different properties from pure mercury.
Yeah the answer above me makes sense...