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Showing 1-15 of 15 Resources
  • Identifying the Key Genes for Regeneration

    Identifying the Key Genes for Regeneration

    Scientists at Work

    (9 min 55 sec) Planarians have an amazing ability to regenerate lost tissues. In this video, scientists knock out two different genes in planaria to start to understand how the process works—and they generate animals with two heads and two tails!

  • The Beak of the Fish

    The Beak of the Fish

    Image of the Week

    The teeth of adult pufferfish are fused to form a beak used for crunching into hard prey such as shellfish.

  • Biological Basis of a Myth

    Biological Basis of a Myth

    Image of the Week

    Hydra is a small freshwater hydrozoan polyp that has the capacity to grow a new individual from any part of its body.

  • Fish Tales

    Fish Tales

    Image of the Week

    Zebrafish blood is generated from stem cells located in the tail region of fish embryos and later from stem cells located in the kidney of the adult fish.

  • Potent Stem Cells

    Potent Stem Cells

    Poster

    The poster from the 2006 Holiday Lectures on Science, Potent Biology: Stem Cells, Cloning, and Regeneration, illustrates the role of stem cells during human embryonic development.

  • Classroom Activities: Stem Cells and Diabetes

    Classroom Activities: Stem Cells and Diabetes

    Activity

    To accompany the lecture series Potent Biology: Stem Cells, Cloning, and Regeneration.

  • Coaxing Embryonic Stem Cells

    Coaxing Embryonic Stem Cells

    Lecture

    (58 min 25 sec) In cloning, a cell's genetic machinery is reprogrammed. Can we similarly coax stem cells to become specific cell types?

  • Understanding Embryonic Stem Cells

    Understanding Embryonic Stem Cells

    Lecture

    (58 min 27 sec) An overview of embryonic development, the progressive differentiation of cells, and properties of embryonic stem cells.

  • Potent Biology: Stem Cells, Cloning, and Regeneration

    Potent Biology: Stem Cells, Cloning, and Regeneration

    Lecture

    Doug Melton and Nadia Rosenthal are leaders in stem cell research, working primarily with mouse and human tissue. They will discuss where embryonic and adult stem cells come from and the biology of how they supply the cells the body needs.

  • Planarian Regeneration and Stem Cells

    Planarian Regeneration and Stem Cells

    Scientists at Work

    (11 min 47 sec) A mini-documentary discussing the remarkable regenerative capabilities of the planarian, and how HHMI researcher Alejandro Sánchez Alvarado uses them to study the biology of stem cells.

  • Human Embryonic Development

    Human Embryonic Development

    Animation

    (2 min 18 sec) Human embryonic development depends on stem cells. During the course of development, cells divide, migrate, and specialize. Early in development, a group of cells called the inner cell mass (ICM) forms. These cells are able to produce all the tissues of the body. Later in development, during gastrulation, the three germ layers form, and most cells become more restricted in the types of cells that they can produce.

  • Differentiation and the Fate of Cells

    Differentiation and the Fate of Cells

    Animation

    (1 min 29 sec) As a human embryo develops, its cells become progressively restricted in the types of specialized cells that they can produce. Inner cell mass (ICM) cells of the blastocyst can make any type of body cell. Gastrula-stage cells can give rise to the cells of a given germ layer. Later, cells become even more restricted. For example, the pancreatic bud of the endoderm layer can only make the cells of the pancreas.

  • Cytoplasmic Factors

    Cytoplasmic Factors

    Animation

    (57 sec) Cytoplasmic factors play a significant part in determining how a cell develops. This segment discusses their importance in turning the appropriate genes on and off for proper development.

  • Creating Embryonic Stem Cell Lines

    Creating Embryonic Stem Cell Lines

    Animation

    (1 min 38 sec) The inner cell mass (ICM) cells of blastocyst-stage early human embryos can be removed and cultured. These cells can be grown in the lab indefinitely. Various growth factors cause these cells to develop into a variety of differentiated cells, such as muscle or nerve cells.

  • Somatic Cell Nuclear Transfer Animation

    Somatic Cell Nuclear Transfer Animation

    Animation

    (52 sec) Somatic cell nuclear transfer (SCNT) is a technique for cloning. The nucleus is removed from a healthy egg. This egg becomes the host for a nucleus that is transplanted from another cell, such as a skin cell. The resulting embryo can be used to generate embryonic stem cells with a genetic match to the nucleus donor (therapeutic cloning), or can be implanted into a surrogate mother to create a cloned individual, such as Dolly the sheep (reproductive cloning).