What do the polar bears, reindeer, and shrubs that live in a single area makeup

They form an ecosystem.

Explanation:

Different organisms that thrive in a single region in combination form an ecosystem. On certain occasions, it is also illustrated as the composite association amongst all the constituents, that is, whether they are non-living or living present within a specific region.  

Within an ecosystem, one can witness a great degree of biodiversity, as all the constituents found within an ecosystem relies heavily upon each other for one thing or another. A healthy balance between all the components that form an ecosystem makes it a sustainable ecosystem.  

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.