CC (Carbon Copy), the first cat produced from a clone, was created from an ovari
ID: 101928 • Letter: C
Question
CC (Carbon Copy), the first cat produced from a clone, was created from an ovarian cell taken from her genetic donor. Rainbow, a calico cat. The diplold nucleus from the cell was extracted and then injected into an enucleated egg. The resulting zygote was then allowed to develop in a petri dish, and the cloned embryo was implanted in the uterus of a surrogate mother cat, who gave birth to CC (see the photo below). Carbon Copy with her surrogate mother. Cattle, sheep, rats, dogs, and several other species have been cloned using nuclel from somatic cells. Embryos and adults produced by this approach often show a number of different mitochondrial defects. Explain possible reasons for the prevalence of mitochondrial defects in embryos created by nuclear transfer cloning. Drag the terms on the left to the appropriate blanks on the right to complete the sentences. Terms can be used once, more than once, or not at all.Explanation / Answer
Mitochondrial defects often involve processes of oxidative phosphorylation and/or other essential mitochondrial functions that are dependent not only on the mitochondrial genome, but also on the nuclear genome. When a nuclear genome is transferred, it may contain mutant genes that negatively influence mitochondrial function that were compensated for in the original donor cells, but not in the recipient. In addition, enucleated eggs invariably contain both normal and defective mitochondria. When a nuclear genome is transferred to an enucleated egg, mitochondrial defects may arise from an uncompensated defective nuclear genome, the heteroplasmic condition of the egg, or a combination of the two. A disease occurs when the mitochondrial mutational load exceeds a tissue-specific threshold, which is generally low in highly metabolic tissues such as brain, heart, and muscle.