Answer:
The correct answer is "#2 and #3 only"
Explanation:
A and a are alleles, and R and r are alleles. Alleles of a gene are found at the same locus on homologous chromosomes. Every pair of the alleles depicts the genotype of a particular gene. Homozygous genotype occurs when two similar alleles at same locus and heterozygous in case of two nonidentical alleles. Due to the alleles there occurs a change in the appearance. An alleles create differences in gene.
This Allows organisms such as bacteria to rapidly adjust their transcription patterns in response to environmental conditions. in addition regulatory sites on prokaryotic DNA are typically located close to transcription promoter sites - and this plays an important part in gene expression
it separates the inside of the cell from the environment outside and it controls substances moving in and out of the cell (selectively permeable)
Eukaryotes are organisms whose cells have a nucleus enclosed within a nuclear envelope.