Which observation does not indicate that a chemical reaction has occurred?

Which of these is one of the nitrogenous bases in dna? a. proline b. leucine c. glycine d. thymine

Introducing minvasive species to an ecosystem results in an increase in biodiversity is it true or false

Match the order of the levels of organization in nature with the correct description. example: atoms are fundamental units of matter= level 1levels- 2,3,4,5,6,7,8.now what levels are these? population consists of organismscells consist of moleculesecosystems consist of communities interacting with there environmentmolecules consist of atomsthe biosphere consist of all ecosystems on earthcommunities consists of populationorganisms consist of cells