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Found Embryonic 30 times.

Displaying results 1 to 10.

1. Angioblast
* A cell in the embryo which develops into blood vessel tissue. * An embryonic mesenchymal tissue which differentiates into the blood cells and blood vessels.

2. Anther culture
A plant culturing technique in which immature pollen is made to divide and grow into tissue (either callus or embryonic tissue) in either a liquid medium or on solid media. Pollen-containing anther s are removed from a flower and put in a culture medium; some microspheres survive and develop into tissue. If embryonic tissue develops, it's put in a medium favorable for shoot and root development; if it's callus tissue, it's put in a solution of hormones that will spur it to differentiate and develop shoot and root tissue.

3. Apical meristem
A meristem (embryonic tissue) at the tip of a shoot or root that is responsible for increasing the plant's length.

4. Autosomal recessive
An autosomal recessive gene is one which is required in two copies on an autosome to be active in an organism. For instance, a person who carry two copies of the same abnormal gene (in other words, this person is homozygous for the gene) will experience effects from that gene (for instance, he or she might then suffer from a disease coded by that gene). The gene can be inherit ed from both parents who carry the gene; sons and daughters have an equal chance of inheriting the gene. If a person has a genetic disease but his or her parents seem normal, then this probably means that: * The parents of this person are heterozygous , unaffected carriers of the disease, or * The person inherited one copy of the gene from a parent, and the other "good" copy underwent a mutation early in the person's embryonic development

5. Barr body
Inactivated X-chromosome in mammalian females. Although inactivated, the Barr body is replicated prior to cell division and thus is passed on to all descendant cells of the embryonic cell that had one of its X-chromosomes inactivated.

6. Carcinoembryonic antigen (CEA)
This is an antigen in blood which is elevated in certain cancers of epithelial origin, notably colon, breast, lung and stomach. CEA is a molecule expressed on surfaces of epithelial cells during embryogenesis but is later confined to only the apical surface. Its function is related to cell adhesions. Tumor formation is accompanied with elevated expression of CEA. Blood CEA levels is a tumor marker to detect the recurrence of cancer or residual activity of cancer after surgery. However, CEA is a non-specific marker of cancer, and may be elevated in noncancerous conditions such as cigarette smoking, ulcerative colitis, liver disease, and lung infection. Therefore, CEA is not useful as a screening test. (Normal levels of serum carcinoembryonic antigen are 0 to 2.5 ug/L.)

7. Diploblastic
Describes an animal which, as an embryo , had two distinct embryonic tissue layers - the ectoderm and endoderm . This is in contrast to animals which are triploblastic (has three distinct tissue layers) and those which do not have any distinct tissue layers as an embryo (nor organs and distinct tissues as an adult). Jellyfish and comb jellies are diploblastic animals.

8. Ectoderm
The outer layer of cells in embryonic development; gives rise to the skin, brain, and nervous system . Also, the outermost tissue layer in flatworms.

9. Ectogenesis
Developing an embryo or embryonic tissue in vitro , or within an artificial environment.

10. Endoderm
The inner layer of cells in embryonic development that gives rise to organs and tissues associated with digestion and respiration. Also, the inner tissue layer in flatworms.

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