Trisomy 13 in humans causes Patau syndrome and is usually a lethal condition. Retinoblastoma (RB) is an autosomal dominant type of childhood cancer caused by mutations in the RB gene on Ch 13. Consider a family in which a man with a very rare adult onset form of RB and a normal woman had two sons and a daughter. One son was karyotypically normal but had RB, the daughter had Patau syndrome and RB, and the second son had Patau syndrome but not RB. (Hint) Draw out the chromosomes with the appropriate alleles for RB on paper first. What are the genotypes and karyotypes of the mother and father? Describe one scenario explaining the cellular events by which the daughter might have arisen.

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction. this is an example of speciation.

What two factors does carrying capacity compare? population size and resource use population growth and resource availability resource use and time population size and time

(me out over the last several centuries, scientists have made the following broad observations while investigating several branches of the life sciences: -the fossil record shows that different types of organisms have existed at different times in earth's history. -many organisms have similar body structures that seem to be adapted to different ways of living in their environment. -organisms of different species often share similarities in stages of embryonic development. -many species share genetic similarities, and almost all organisms use the same basic building blocks to construct proteins. -often, the extent of two species' similarities can be predicted from their geographic closeness to each other. -a great deal of change has been observed among species that have experienced strong selective pressures through many generations. scientists have carefully considered and rigorously tested the observations listed above. when scientists offer a of these observations, they are making 1.) testable explanation, deductive explanation 2.) scientific interference, scientific law