Answer:
Changes in gene expression
Explanation:
This phenomenon is the result of changes in gene expression. That means, how the information in the DNA is used by the cell. The genes that are active in the cells of the brain will be very different from the genes that are active in the cells of the bone marrow.
These patterns of gene expression are different for each cell, and dictate the identity of that cell. Gene expression patterns are controlled by a variety of factors in the cell that allow tissue-specific expression, such a transcription factors.
This can also be facilitated by another layer of regulation called epigenetics, which literally means "on top of" genetics, and refers to modifications of DNA (and the proteins around it), that can reflect and influence the activity of the genes within.
Oil and water separate because they have different densities.
The answer is 3:1.
If we imagine that plant has two alleles for the
trait, we can dominant allele represent with P represents and recessive allele with p. To get purebred monohybrid in the first generation, parents must be a dominant homozygote (PP) and a recessive hetero<span>zygote (pp):
Parental generation: PP x pp
The first generation: Pp Pp Pp Pp
Pp represents a heterozygote.
If we cross these heterozygotes:
The first generation: Pp x Pp
The second generation: PP Pp Pp pp
If dominant allele determines the phenotype, there will be 3 plants (one PP and two Pp) with one phenotype and only 1 plant </span><span>(pp)</span> with another phenotype and vice versa.
