(Variation.)Heritable differences that exist in every population are the basis for natural selection.
(Overproduction). Competition between offsprings for resources.
(Adaptation.) a trait that helps an organism survive and reproduce.
Descent with Modification.
Answer:
The Respiratory system allows entry of oxygen into the body and release Carbon Dioxide. The Oxygen travels across lung tissue into blood vessels and the blood carries the oxygen around the body. Thus the Respiratory and Circulatory system work together in gas exchange which is vital in Homeostasis
The term used for a group of words that does not contain a verb or a subject and that acts as a single part of speech is D. a phrase.
