Which statement best describes the process of crossing over? (1 point) O Pairs of homologous chromatids are divided in half and distributed randomly into new diploid cells.
O Pairs of homologous chromosomes are divided in half and distributed randomly into new haploid cells.
O Homologous chromosomes pair up, and non-sister chromatids exchange genetic material
O Homologous chromatids pair up, and non-sister chromosomes exchange genetic material.

The meselson-stahl experiment demonstrated that dna replication is semiconservative. in the figure, semiconservative replication is illustrated by

Read the following scenario to answer the following question. over the past 60 years, many amphibian species have experienced significant population declines, and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. when most populations of a wide-ranging amphibian species are lost and the few remaining populations are widely separated, we expect to see that a. the founder effect becomes increasingly important b. microevolution no longer occurs c. gene flow between populations is reduced d. artificial selection becomes a greater factor in microevolution

Study this image which statement best describes the rock shown check all that apply