of multipotent stem cells: hematopoietic stem cell and mesenchymal stem cell.


- Nucleic acid-protein structures in the nucleus of a cell. Chromosomes are composed chiefly of DNA, the carrier of hereditary information. Chromosomes contain genes, working subunits of DNA that carry the genetic code for specific proteins, interspersed with large amounts of DNA of unknown function. A normal human body cell contains 46 chromosomes; a normal human gamete (egg or sperm), 23 chromosomes.


- The contents of a cell, other than the nucleus cytoplasm, consists of a fluid containing numerous structures, known as organelles, that carry out essential cell functions.


- Extension of a nerve cell, typically branched and relatively short, that receives stimuli from other nerve cells.


- The process whereby an unspecialized early embryonic cell acquires the features of a specialized cell such as a heart, liver, or muscle cell.


- A chemical, deoxyribonucleic acid, found primarily in the nucleus of cells. DNA carries the instructions for making all the structures and materials the body needs to function.


- The upper, outermost of the three primitive germ layers of the embryo that will give rise to the skin, hair, nails, nerve, and brain including the retina of the eye.


- In humans, the developing organism from the time of fertilization until the end of the eighth week of gestation, when it becomes known as a fetus.

Embryonic germ cell

- Cells found in a specific part of the embryo/fetus called the gonadal ridge, and normally develop into mature gametes.

Embryonic stem cell (ESC)

- Primitive (undifferentiated) cell from the

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