In pea plants the allele for tall plants in dominant to the allele for short plants, and the allele for purple flower colour is dominant to the allele for white flower colour. What is the genotype of a short plant produced from a cross between a true-breeding purple flowered pea plant and a true-breeding white flowered pea plant? * 1.TTPP
2.ttpp
3.ttPP
4.ttPp
5.TtPp

The correct answer is - 4. ttPp

Explanation:

Given - tall is dominant over short pea plant

let assume T is dominant and t is short which is recessive

Similarly, P for dominant purple flower and p for white flower

The offspring has a short plant which means it has both t allele or recessive allele for the height of a plant by the cross of a true-breeding purple and true-breeding white:

    P   P

p   Pp Pp

p   Pp Pp

This means the offspring would have a heterozygous case for the genotype of the flower of the pea plant

Thus, the correct answer is ttPp

its 42

i say its d?

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.