A concentration gradient is a of concentrations between two regions.

(6.02 mc)what affect do marine protected areas have on environmental quality? they increase environmental quality by preventing resource overuse. they increase environmental quality by adding new species. they decrease environmental quality by removing all human activity. they decrease environmental quality by adding recycling facilities.

What is the tern used to describe an individual that of a recessive allele that causes disease, but is otherwise healthy? a. carrier b. polycite c. target d. afflicted

Satellites orbit earth in the a) mesosphere b) troposphere c) stratosphere d) thermosphere