You obtain an egg cell from the ovary of a white mouse and remove the nucleus from it. You then obtain a nucleus from a liver cell from an adult black mouse. You use the methods of nuclear transplantation to insert the nucleus into the empty egg. After some prompting, the new zygote divides into an early embryo, which you then implant into the uterus of a brown mouse. A few weeks later, a baby mouse is born. What color will it be? Why?

Verified step by step guidance

1. Understand the concept of nuclear transplantation: In this process, the nucleus of one cell is removed and replaced with the nucleus of another cell. The genetic material (DNA) in the nucleus determines the traits of the organism.
2. Identify the source of the nucleus: The nucleus used in this case comes from a liver cell of an adult black mouse. This nucleus contains the complete genetic information (genome) of the black mouse.
3. Recognize the role of the egg cell: The egg cell from the white mouse has had its nucleus removed, meaning it no longer contains its own genetic material. It only provides the cytoplasm and cellular machinery necessary for development.
4. Understand the role of the surrogate mother: The brown mouse serves as the host for the embryo, providing the environment for the embryo to develop, but it does not contribute any genetic material to the offspring.
5. Conclude the offspring's traits: Since the genetic material in the nucleus determines the traits of the organism, and the nucleus came from the black mouse, the baby mouse will have the genetic traits of the black mouse, including its black fur color.

Key Concepts

Nuclear Transplantation

Nuclear transplantation is a technique where the nucleus of a donor cell is transferred into an enucleated egg cell. This process allows the egg to develop into an embryo using the genetic material from the donor nucleus. In this scenario, the nucleus from a liver cell of a black mouse is inserted into the egg cell of a white mouse, which is crucial for understanding the genetic outcome of the resulting organism.

Genetic Expression and Phenotype

The phenotype of an organism, such as its color, is determined by the expression of genes inherited from its parents. In this case, the baby mouse will express the traits associated with the black mouse's liver cell nucleus, as the genetic information from the nucleus dictates the development of the organism. Thus, the color of the baby mouse will reflect the genetic traits of the black mouse.

Mitochondrial DNA and Maternal Influence

While the nucleus contains the majority of genetic information, the egg cell also contributes mitochondrial DNA, which is inherited maternally. However, in this scenario, the phenotype is primarily influenced by the nuclear DNA from the black mouse. The maternal influence from the white mouse's egg is less significant in determining the color of the offspring, as the dominant traits from the black mouse's nucleus will prevail.