Fat cells in the body increase in size when energy intake is greater than energy expended, resulting in weight gain. a. True
b. False

[120 total points] (public health) in one of the largest human experiments ever conducted, in 1954 a randomized controlled trial was run to see whether a vaccine developed by a doctor named jonas salk was effective in preventing paralytic polio. a total of 401,974 children (ages 6–9), chosen to be representative of those who might be susceptible to the disease, were randomized to two groups: 200,745 children (the control group c) were injected with a harmless saline solution (a placebo) and the other 201,229 children (the treatment group t) were injected with salk’s vaccine.what was the point of giving saline solution to the children who didn’t get the vaccine? explain briefly.

Poliovirus is an rna virus of the picornavirus group, which uses its rna as mrna. at its 5' end, the rna genome has a viral protein (vpg) instead of a cap. this is followed by anontranslated leader sequence, and then a single long protein-coding region (~7000 nucleotides), followed by a poly-a tail. observations were made that used radioactive amino acid analogues. short period use of the radioactive amino acids result in labeling of only very long proteins, while longer periods of labeling result in several different short polypeptides. what conclusion is most consistent with the results of the radioactive labeling experiment? a) host cell ribosomes only translate the viral code into short polypeptides.b) the rna is only translated into a single long polypeptide, which is then cleaved into shorter ones.c) the rna is translated into short polypeptides, which are subsequently assembled into large ones.d) the large radioactive polypeptides are coded by the host, whereas the short ones are coded for by the virus.

When do people generally experience rapid growth for a second time? a. between the ages of 3 and 9 b. between the ages of 9 and 12 c. between the ages of 13 and 20 d. between the ages of 25 and 29 which action occurs in the third stage of cell division? a. the nuclear material of cell is copied exactly. b. the nuclear membrane disappears. c. the cell forms two nuclei d. the nuclear material separates, with half moving to either side of the cell.