Select the correct answer.
which observation did researchers make in studies on separated twins?
a. separated twins develop traits that differ according to the environments in which they are raised.
b. separated twins tend to have the same behavioral characteristics, regardless of environment.
c.
although separated twins share behavioral traits during their early development, the environment might suppress such traits later.
d.
environmental factors play a more dominant role than genes do in shaping an individual's behavioral traits.
e.
certain physical traits of separated twins differ due to environmental influences.

A. Separated twins develop traits that differ according to the environments in which they are raised.

Explanation:

Despite sharing exactly the same DNA, identical twins can have completely different personalities. Until now, researchers did not know exactly by what mechanisms individuals overcame their genetic programming and differentiated themselves throughout life, forming their individuality. However, after some research, the scientists concluded that the environment has some influence on the personality of the twins. They believe that identical twins who were created separately have different personalities due to the influence of the environments.

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 menstrual cycle – higher tier. negative feedback mechanisms affect the production of hormones in the menstrual cycle. oestrogen also stimulates the release of lh (luteinising hormone) from the pituitary gland, which in turn controls the production of progesterone.