Using powerful new sequencing technologies, investigators can now catalog every rna molecule made by a cell and determine at what quantities these rnas are present. in an experiment, researchers measured the relative quantities of two different mrnas—one transcribed from gene a, the other from gene b—in two different cell types. gene b is expressed in both the liver and the brain whereas gene a is expressed in the brain but not in the liver. which most likely encodes a housekeeping protein?

During crossing-over, a. genetic material is exchanged between nonsister chromatids, resulting in new combinations of alleles. b. nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. c. one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles. d. sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. e. genetic material is exchanged between sister chromatids, resulting in new combinations of alleles.