Cystic fibrosis is a genetic disorder in which a particular gene does not make protein the way that it otherwise normally would. Given that cystic fibrosis is a genetic disorder, how would an individual most likely contract this disease? A. a person’s parents would have to carry genetic material for cystic fibrosis within their chromosomes which could then be passed down.

B. a person’s parents would have to carry genetic material for cystic fibrosis within their chloroplasts which could then be passed down.

C. a person would have to have been exposed to environmental influences such as living next to a nuclear power plant

D. genetic disorders can be transmitted in so many ways that it is impossible to tell how a person acquired the disease.

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.

the missing space is phylum

answer; hydrologic cycle;