All organisms do have a closed circulatory system
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Answer:
AZT is a thymidine analog
Explanation:
Azidothymidine (AZT) is an antiviral drug used for the treatment of the Human immunodeficiency virus infection (HIV/AIDS) by preventing the transmission of HIV from infected cells. AZT is capable of suppressing the activity of the enzyme reverse transcriptase of the retroviral HIV genome, which enables it to copy RNA into DNA. In infected cells, this double-stranded DNA is integrated into the host genome which is then instructed to produce identical HIV copies. AZT is a thymidine analog that is incorporated into DNA and thus interferes with DNA synthesis, thereby inhibiting cell proliferation.
The answer is operon. These set of genes are transcribed together because they share a single promoter and operator. Therefore they are transcribed into one mRNA and translated together. These genes are, therefore, expressed together at all times. Examples are the tryptophan and lac operons of Escherichia coli
Tuberculosis vaccines are vaccinations intended for the prevention of tuberculosis. Immunotherapy as a defence against TB was first proposed in 1890 by Robert Koch. Today, the only effective tuberculosis vaccine in common use is bacilli Calmette-Guérin, first used on humans in 1921.
The answer would be : <span>both ethnologists and comparative behaviorists were correct.
Hope this helps !
Photon</span>