10. the table below lists enzymes that function in different locations in the human body, and the normal ph
and temperature ranges of these locations.
enzymes in the human body
location of enzyme
ph
perature (o
ato
use your understanding of the structure and function of enzymes to
predict how the activity of pepsin will change after it moves from the stomach to the small intestine
explain your prediction using data from the table
describe how changes in ph and temperature affect enzyme activity
predict how a fever of 40°c would affect enzyme activity (2006)

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.