Individuals with Beckwith-Wiedemann syndrome (BWS) develop sporadic tumors due to a mutation in an imprintable gene, p57, on chromosome 11. Normally, p57 regulates the cell cycle. The imprint on p57 is such that only the maternal allele is expressed. A heterozygous normal couple has two children with BWS and one normal child. How is it possible that both parents have the mutant p57 allele to pass along, but these parents do not themselves show the cancerous phenotype

What would be the result if crossing over did not happen during meiosis in humans? a. there would be less genetic variation in humans. b. parents would be more likely to look like their children. c. the human population could not reproduce. d. children would have more chromosomes.

What advantages does a pedigree have over a written passage?

The graph shows the amount of global warming happening in different ecosystems. which populations of organisms will likely decline the most as a result of climate change, and why? a.coral reefs because of the loss of the symbiotic algae living within their bodies b.penguin populations because the fish they eat will move into warmer waters c.mountain-dwelling birds because rising sea levels will relocate their food sources d.large cats in the rainforest because of decreased habitat loss for their prey