Apharmaceutical company manufactures medicine to reduce pain caused by migraine headaches. the company is investigating whether a new medicine is more effective in reducing pain than the current medicine. a random sample of 500 participants who experience migraines was selected, and the participants were randomly assigned to one of two groups of equal size. the first group received the current medicine and the second group received the new medicine. when a participant experienced a migraine, he or she was instructed to take the medicine and, 15 minutes after taking the medicine, to rate the pain relief on a scale from 1 to 10, with 1 being no relief to 10 being complete relief. at the end of six months, the average pain relief for each participant was calculated. which of the following is the best description of the study?
a. an experiment using a completely randomized design
b. an experiment using a matched-pairs design
c. an observational study using a simple random sample
d. an observational study using a cluster sample
e. an observational study using a stratified sample

Hello, Answer is A.

Explanation:

An experiment using a completely randomized design. A completely randomized design is an experimental design in which the experimenter randomly assigned subjects to one of two treatment conditions. In the question, it is stated that a random sample of 500 participants were selected, and the participants were randomly assigned to one of two groups of equal size. Hence, the best description of the study is an experiment using a completely randomized design

transcription is a process in which information is rewritten. it is something our cells must do, in a more specialized and narrowly defined way. in biology, transcription is the process of copying out the dna sequence of a gene in the similar alphabet of rna. it needs to happen in the nucleus because that's where the dna is. dna is always inside the nucleus unless the cell is dividing.

transcription is the first step in gene expression, which involves copying a gene's dna sequence to make an rna molecule. transcription is performed by rna polymerases. it has three stages: initiation, elongation, and termination. rna molecules must be processed after transcription in eukaryotes.

explanation:

long version:

the protein synthesis consists two processes which are, transcription and translation. transcription takes place in the nucleus. it uses dna as a template to make an rna molecule. rna then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. transcription is the first part of the central dogma of molecular biology: dna → rna. it is the transfer of genetic instructions in dna to messenger rna (mrna). during transcription, a strand of mrna is made that is complementary to a strand of dna.  

these three stages are:

  initiation: in which   is the beginning of transcription.occuring 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.

    elongation: in which 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.

    termination: in which 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 answer is :