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Modern Genetics

Stem cells

  • 4 things to know
  • Papers 1 and 3

Overview

Recall questions on totipotent, pluripotent and multipotent stem cells and where they are found, the medical promise and ethical concerns of embryonic stem cells, and producing induced pluripotent stem cells from fibroblasts with transcription factors.

What you need to know

Answer each one before you reveal it.

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Process

Explain the mechanism by which differentiated fibroblasts become pluripotent during iPS cell production.

Key term

What medical opportunities do pluripotent stem cells from embryos provide?

Key term

What are fibroblasts?

Key term

What is artificially introduced into fibroblasts to reprogram them into iPS cells?

Questions from this subtopic

Each one with the model answer underneath.

  1. 1

    Define a stem cell.

    Model answer

    An undifferentiated cell capable of dividing to produce more stem cells and differentiating into specialised cell types.

  2. 2

    What distinguishes totipotent stem cells from other stem cell types?

    Model answer

    Totipotent cells can differentiate into any cell type including extraembryonic tissues such as the placenta.

  3. 3

    What range of cell types can multipotent stem cells produce?

    Model answer

    A limited range of cell types within a particular tissue or organ.

  4. 4

    At what stage of development are totipotent cells found?

    Model answer

    In the early embryo up to approximately the 16-cell stage.

  5. 5

    Where in the blastocyst are pluripotent cells located?

    Model answer

    In the inner cell mass.

  6. 6

    Why is the destruction of embryos an ethical concern in embryonic stem cell research?

    Model answer

    Obtaining embryonic stem cells requires the destruction of embryos, which some consider morally problematic.

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