INTRODUCTION TO MICROSCOPY CELL BIOLOGY
DIFFERENTIATED CELL
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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When are embryonic stem cells present in a multicellular organism?
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throughout the life span
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3-5 days after conception
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only after birth
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1-4 months after conception
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Explanation:
Detailed explanation-1: -A very specific and important event occurs after 5–6 days: the blastocyst changes very subtly and the cells in the inner cell mass lose the ability to read all of their DNA. In other words, cells are no longer pluripotent after this point in development.
Detailed explanation-2: -Researchers harvest the embryo stem cell at the Day 4 or 5 stage. This time frame is crucial, because it is just after the embryo begins dividing multiple cells within itself, but before those cells begin to differentiate.
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