Fill in the blood type for samples of the following scenarios. a ) anti-a not present, anti-b present, anti-rh present b) anti-a present, anti-b not present, anti-rh not present c) anti-a not present, anti-b not present, anti-rh not present d) anti-a present, anti-b present, anti-rh present e) anti-a not present, anti-b not present, anti-rh present

The answers are as follows:

(a) Blood type is  A negative

(b) Blood type is B positive

(c) Blood type is  AB positive

(d) Blood type is  O negative

(e) Blood type is  AB negative

With blood type A  negative, the body produces antibodies against B and Rh

With blood type B positive , the body produces antibodies against  A only

With blood type AB positive, the body produces no antibodies at all against A,B or Rh

With blood type O negative the body produces antibodies against A, B and Rh

With blood type AB negative the body produces antibodies against Rh only.

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.