In 1997, Dolly the Sheep Was Cloned

question 30

Multiple Choice

In 1997, Dolly the sheep was cloned. Which of the following processes was used?

• A) use of mitochondrial DNA from adult female cells of another ewe
• B) replication and dedifferentiation of adult stem cells from sheep bone marrow
• C) separation of an early stage sheep blastula into separate cells, one of which was incubated in a surrogate ewe
• D) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate
• E) isolation of stem cells from a lamb embryo and production of a zygote equivalent

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Definitions:

Fossil Species

The remains or traces of organisms from a past geologic age, preserved in sedimentary rock, which provide valuable information about Earth's history.

Oldest Rock

The earliest forms of solid rock on Earth, providing evidence of the planet's geological history and surface conditions.

Billion Years

A time scale used in geology and astronomy to describe events or processes that happened a billion years ago or the age of geological formations.

Isotopic Age

The determination of the age of a mineral, rock, or geologic event based on the ratio of parent isotopes to daughter isotopes within a given system.