Lupus, a condition in which the body attacks its own cells, is an example of
an allergic disorder.
an immunodeficiency disorder.
a cancer of the immune system.
an autoimmune disorder.

The study of interaction between living organisms and their enviroment is called (a) phytogeography (b) ecology (c) phytosociology (d) ecosystem

Hurry which of these is true about index fossils? a) are very scarcely found b) used as guides in relative dating c) found in the youngest layer of the rock d) used as reference points in absolute dating

Which statement correctly describes a way that mutations increase the likelihood that a species will survive in a changing environment