How have humans changed the global nitrogen cycle? A. They have greatly decreased the amount of fixed nitrogen.
B. They have raised the speed at which nitrogen travels through the
cycle.
C. They have lowered the speed at which nitrogen travels through the
cycle.
D. They have greatly increased the amount of fixed nitrogen.

Which way do the nitrogenous bases in dna pair up? a. a and g; t and c b. a and c; t and g c. a and t; g and c d. a and a; t and t; g and g; c and c

The reactions that occur in the ribosome, where amino acids are combined to form proteins are anabolic or catabolic?

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area