A human grows in size from a zygote (fertilized egg) to an e…

A human grows in size from a zygote (fertilized egg) to an embryo to an adult. This is primarily through the production of additional cells. The process that produces the additional cells is [a]. The cells in the multicellular adult differ in structure and function because they [b].

A diploid salamander experiences a failure in cell division…

A diploid salamander experiences a failure in cell division that results in the production of tetraploid offspring. The diploid individuals each contain 2 copies of 4 chromosomes, but the tetraploid individuals contain 4 copies of the 4 chromosomes. Diploid salamanders produce haploid gametes (1 copy of each chromosome per gamete), and the tetraploid salamanders produce diploid gametes (2 copies of each chromosome per gamete). Under the biological species definition, should the diploid and tetraploid salamanders be considered separate species, or the same species?