The loss of genes that occurred as the horse nematode (Ascaris megalocephala) evolved into a specialized parasite, with only 6 chromosomes in each diploid cell, was most likely due to: deletion of one or more chromosomes deletion of the entire genome duplication of the entire genome duplication of one gene duplication of one chromosome

A scientist investigating the genome of two related individuals observes a difference of a few nucleotides in one individual compared to the other. The nucleotide differences are in a region of noncoding DNA on chromosome 1. Would these differences be considered a mutation? Why or why not? Yes, the difference in nucleotide sequences between the individuals is a mutation because it will affect the phenotype of the two individuals. Yes, any heritable variation in the nucleotide sequence is considered a mutation, even if that variation is in a noncoding region of DNA. Not enough information was provided to determine if this nucleotide difference is a mutation because the effect on phenotype is unknown. No, the change in nucleotide sequence doesn't appear in a coding region of the DNA and so can't be a mutation.

Why is it easier to identify spontaneous mutations in bacteria than in most eukaryotes?     The mutations occur at a much higher frequency.     Because bacteria have smaller genomes.     The mutations can be induced via exposure to the bacteriophage.     The mutations are expressed directly in descendant cells because bacteria are haploid.     The mutations are visible as color changes within a bacterial colony.