Which term best discribes the temperature and weather conditions of an organism environment?

When the body has a weakened immune system, the production of antibodies is increased.

Paleontologists have found plant fossils deep within the layers of the north polar region. these leaf fossils have been labeled as to the rock layers they were found in, with the lower numbers being layers close to the earth's surface and higher numbers representing deeper layers. according to the numbers of these four leaf fossils, what might you infer?

Characterized by hyaline cartilage connecting the bony portions