Emma and anna are identical twins who were adopted by different families a few weeks after their birth. although genetically identical, they grew up with different physical and psychological characteristics. for example, though both inherited a tendency to grow large, anna was slim and athletic because of the active lifestyle practiced in her adoptive family. this variability can be explained by how:
a. each zygote is unique. b. longevity genes can make an individual less vulnerable to certain diseases. c. for each genotype, a range of phenotypes can be expressed. d. mutated genes can be a source of genetic variability.

List three reasons why people might be fascinated by something as dangerous as a nuclear weapon.

Afull irb committee meeting is convened and one agenda item is a new research proposal to evaluate how mothers interact with their learning-disabled child. the inclusion criteria require the children to be a minimum of five years of age. the protocol requires the mother of the child to look at the child without any expression and not to talk to the child for three minutes. the committee determined that the mother's required task may upset the child. the irb approved the study with appropriate language in the parental permission form regarding the possibility that children might become upset. after the start of the study, the principal investigator reports to the irb that, as expected, one of the children became upset. the incident was handled according to the protocol and the child is fine. what should the irb do with regard to this report?

If a swimmer is traveling at a constant speed of 0.85 m/s, how long would it take to swim the length of a 50m olympic sized pool?