What distinguishes one element from another

Are produced in the light reactions and used in the calvin cycle. a)nadh and atp b)electrons and sugar c)nadt+ and adp d)sugar molecules

When does dna replication(make a copy of itself)?

The eruption of a nearby volcano causes a prairie ecosystem to receive a lot less sunlight.which of these is the most likely effect on the ecosystem? a-an increase in biodiversity. b-an increase in immigration to the area. c-a decrease in available water. d-a decrease in plant growth.