Aprotein that detects a signal molecule
and performs an action in response is
called a
a. receptor.
b. ligand.
c. vesicle.
d. proton.

What is called the "building block" of life?

Indicate whether the following statements about the biases in the fossil record are true or false. a) inland species are more likely to be preserved than marine species b) organisms with hard body parts are more likely to be preserved than are those composed soft tissues. c) species that existed over a larger area are more likely to be preserved than species existing over a smaller area. d) organisms that lived very long ago are more likely to be found as fossils than organisms that lived relatively recently e) the fossils of larger organisms are more likely to be found than the fossils of smaller organisms

During the winter, this species of fox has white fur, but in the summer, it has brown fur. what environmental change may have lead to this fox's fur color? snow cover increase in sun's brightness volcanic eruption global warming