The correct answer is (4) Autotrophic organism.
Green plants make their own food by the process of photosynthesis using sunlight. Most of the autotrophs use carbon dioxide, sunlight and carbon dioxide to produce glucose that is used by the plants to obtain energy. Most of the oxygen comes from these organisms and decrease in the number of green plants can lead to several problems due to decrease in the amount of oxygen. Example: green plants, algae, and even some bacteria. This food and oxygen is produced by the action of autotrophic organisms
I would say immigration only.
emigration would theoretically reduce the genetic variation as unique individuals leave, but immigration would bring unique traits into circulation in an ecosystem.
I'm not super great at biogy tho so this might not be right... :)
Serch it up might have some answers on there:)
Answer;
-Structural isomers.
Explanation;
-Isomers are molecules that have the same molecular formula, but have a different arrangement of the atoms in space.
-Structural Isomers are molecules which have the same molecular formula but have different connectivities. That is; the molecules have the same molecular formula, but their atoms have different arrangements or bonds.
-For example, butane and isobutane are structural isomers, also called chain isomers. In chain isomers, the carbon atoms are connected in different orders. Isobutane and butane have a molecular formula of C4H10.
DNA is made of a double helix of two complementary strands. When replicating, these strands seperate. Each strand of the original DNA then acts as a template for the production of it's counterpart, which is referred to as semiconservative replication.