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Answer: D. Jacob and Monod
Explanation:
An operon is a region of DNA that consists of a single gene regulated by more than one promoter. An operon is a region of RNA that consists of the coding regions of more than one gene. RNA polymerase is the enzyme that binds to promoters and transcribes the coding regions of genes into RNA.
Jacques Monod was the first to demonstrate the preference for certain substrates over others through his studies of E. coli’s growth when cultured in the presence of two different substrates simultaneously.
A cycadophyta is a biological dividsion, and within this,nthree are three families, and these are; Cycaclaceae, Strangeriaceae and Zamiceae. The plants of these are seed plants, which generally have characteristics, such as a stout, short and tough trunk made of wood, with a crown like span of evergreen leaves, with a cone shape protruding from the centre of the tree.
Sorry, I wasnt able to attach an image, but if you google cycadophyta, this is what they look like.
Sorry for the inconvenience, hope this helps