What do all ecosystems have?

A. biotic p21 only

B. abiotic p21 only

C. producers only

D. biotic and abiotic p21

How is a gene and allele related?

Imagine that the company invented a machine that would double the production of baseballs and bats. In such a case, what would happen to the curve in the graph? O It would stay where it is. 0 It would grow on one axis, but shrink on the other.

Which of the following explains why scientists were opposed to Wegener's theory? A Wegener's evidence did not make sense. B They were afraid of a new idea. C Wegener could not identify a force that could move the continents

What evidence did Darwin used to support his theory of evolution

Mark's misuse of alcohol and other addictive drugs is influenced by genetic factors, by the ready availability of drugs in Mark's neighborhood, and by Mark's failure to accurately assess the risks associated with drug usage.

What activities and body functions of arthropods require the most specialized appendages?

If a diploid cell with 8 chromosomes goes through in meiosis how many chromosomes will the resulting haploid cells have

If trypsin and chymotrypsin become activated within the pancreas and then are released in their active forms into the bloodstream, why would this represent a potentially life-threatening situation?

Which of the following statements correctly relates mutations and survival rates of animals? Mutations always improve the chances of survival for an animal. Mutations sometimes improve the chances of survival for an animal.

Which type of membrane proteins is correctly paired with its function