now you’ll examine an operon that undergoes negative and positive control. the ara operon in e. coli codes for enzymes that metabolize the sugar arabinose, which e. coli can use for energy. as you can see in the diagram, the regulatory protein arac can act as both an activator and a repressor of the ara operon.

You need to make 500ml of 7h9(+) media with 1x adn and 30ug/ml of the antibiotic kanamycin. your stock solutions are 10x adn and 30mg/ml of kanamycin. the solvent is distilled water. how much of each component will you need to make the desired final solution?

Recently, crops of vegetables such as lettuce and green onions have been contaminated, while they are still on the farm, with bacteria that cause food poisoning. how will science influence the way the government responds to prevent an increase in food-borne diseases? because science has shown that lettuce and green onions are not nutritionally valuable, the government may pass laws that ban the sale of lettuce and green onions. because science has shown that there is no way to prevent bacterial contamination, the government may pass laws that punish businesses that buy lettuce and green onions. because science has shown that the washing of hands prevent the spread of infectious diseases among people, the government may pass laws that require hand washing by everyone who handles food. because science has shown there are ways to find the source of the contamination, the government may pass laws that require farm practices that reduce the contamination of lettuce and green onions.

Which feature would you expect to find in a population in which sexual selection depends on male competition?