What is a population?

all the organisms in an ecosystem
a collection of all the abiotic factors in an ecosystem
a collection of all the biotic factors in an ecosystem
a group of organisms of the same kind or species

Describe the relationship and movement between temperature and density in a convection cell. make sure you identify the direction of travel

Why do some dna fragments move farther than others during gel electrophoresis? a. because their shapes are different b. because they are different types of molecules c. because the samples are different colors d. because their masses are different

What is the one part of the nucleotide  that differs among the other different nucle  tides?