What happens when a person who is infected with a herpes virus experiences a cold sore or genital flare-up? They are reinfected by exposure to a different, but closely related herpes virus strain. Copies of herpes virus particles that have escaped the immune system periodically experience conditions that allow them to replicate and infect cells. Copies of the herpes virus genome permanently maintained in host nuclei are periodically "activated." They are reinfected by exposure to the same herpes virus strain. COCO

The National Institutes of Health (NIH) set up a study to determine whether large doses of vitamin C would shorten the length of time it takes to recover from a cold. Three thousand volunteers were split into two groups. For two weeks, members of Group A took 3,000 mg of vitamin C daily. Group B received 3,000 mg of a placebo. At the end of the two-week period, the researchers inserted live cold viruses directly into the noses of all the volunteers. The volunteers in both Group A and B continued to take their daily pills. All the volunteers got colds, and there was no significant difference in the length of time the colds lasted. What is the experimental group in this example? Select the best answer. Group B. Three thousand volunteers. Group A. The live cold virus. Length of time the colds lasted. The vitamin C. Size of pill (3000 mg).

Brad receives a viral vector coronavirus vaccine that uses a specific adenovirus and your immune system mounts a strong immune response. Luis receives an RNA coronavirus vaccine and also has a strong immune response. One year later a new coronavirus variant emerges and neither of the original vaccines protects people from this new variant. A new viral vector vaccine is developed to the variant using the same adenovirus as before. In clinical trials, it is found that the new vaccine protects people that originally received the RNA coronavirus vaccine that Luis had but does not protect people that originally received the viral vector coronavirus vaccine that Brad had. Can you think of an explanation for why the new vaccine didn't protect Brad but did protect Luis?

Which of the following self-replicating biological agents carries only one polynucleotide chain as its genetic material, does not code for any proteins, and does not have any nucleocapsid? the RNA virusoid known as hepatitis delta virusoid the single-stranded RNA virus known as human immunodeficiency virus the double-stranded RNA virus known as rotavirus the double-stranded DNA virus known as pandoravirus the RNA viroid known as citrus exocortis viroid       The human precancerous disorder known as xeroderma pigmentosum is caused by which of the following mutagenic conditions? thymine dimers demethylation deacetylation depurination deamination      7. Who discovered that DNA synthesis in the intact chromosomes of rapidly-growing bacterial cells is continuous on the leading strand, but discontinuous on the lagging strand? Rosalind Franklin and Maurice Wilkins Matthew Meselson and Franklin Stahl Erwin Chargaff and Arthur Kornberg Reiji Okazaki and Tuneko Okazaki James Watson and…