51. Hemoglobin delivers O2 to body cells from the red blood cells a. until the hemoglobin is depleted of O2. b. until the partial pressures of O2 in the two different cells are equivalent. c. although the hemoglobin is never completely saturated. d. by releasing O2 to cells with a higher partial pressure of oxygen. e. until the fluid pressure in the red blood cells is lower.

i would have to say autosomal

the dark variety, as they are not visible on the dark tree barks

explanation:

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.