A scientist is observing cells undergoing division and identifies a cell that contains 15 pairs of homologous chromosomes. However, a new technique allows the scientist to determine that several of the chromosomes have exchanged pieces of genetic material with their homolog. The scientist now knows that which of the following is true? A. The cell is in mitosis and has just completed crossing over
B. The cell is in meiosis II and is ready to complete the second division over
C. The cell is in meiosis and has just undergone crossing
D. The cell is in late anaphase of mitosis

Which phrases describe an extrusive rock? check all that apply. fine texture cooled slowly small crystal size found deep underground different, easily observed minerals

Afarmer has applied a pesticide to control a pest population that is affecting her crops. the pest population has reacted as shown below. which best describes the process that the pest population has experienced due to this environmental change? a genetic diversity b natural selection c natural resistance d genetic resistance

Which of the following scenarios is an example of the bottleneck effect? answers a in south africa, much of the afrikaner population is descended from a small number of dutch colonists. in this population, this is an unusually high frequency of pseudoxanthoma elasticum (pxe), an elastic tissue disorder. b four white-tailed deer are introduced to a park in finland. thirty years after their introduction scientists compare the genes in the population and find that there is no variation. c during the industrial revolution, london's air became filled with soot. as a result, birds started eating more of the lighter moths because they were easier to spot than their darker counterparts. over time, the moth population changed so that there were more darker moths than lighter ones. d 10% of the population of american alligators in an area have the recessive trait albinism. a massive flood results in the death of 80% of the population. of the remaining population, 60% have the recessive trait of albinism.