| chorionic gonadotropin, human | A human hormone made by chorionic cells (in the foetal part of the placenta), hCG is directed at the gonads and stimulates them. HCG becomes detectable (by immunologic means) within days of fertilization and forms the foundation of the common pregnancy tests. The level of hCG in maternal serum also enters as one component in the double and the triple screens used during pregnancy to assign risks of Down syndrome and other foetal disorders. (12 Dec 1998) |
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| chromosomes, human | The structures within the human cell nucleus that contain the hereditary material, DNA. There are 46 chromosomes normally present in the human, including two which determine the sex of individual, xx for the female and xy for the male. Human chromosomes are classified into groups sharing structural similarity in terms of length from the centromere. (12 Dec 1998) |
| chromosomes, human, 1-3 | One of the seven groups of chromosomes containing three pairs conventionally named pairs 1, 2, and 3. The chromosomes in this group, also called group a, are large chromosomes with centromeres approximately in the middle. (12 Dec 1998) |
| chromosomes, human, 13-15 | The fourth of the seven groups of chromosomes containing three pairs conventionally named pairs 13, 14, and 15. The chromosomes in this group, also called group d, are medium sized with centromeres in the acrocentric position. (12 Dec 1998) |
| chromosomes, human, 16-18 | The fifth of the seven groups of chromosomes containing three pairs conventionally named pairs 16, 17, and 18. The chromosomes in this group, also called group e, are rather short and submetacentric. (12 Dec 1998) |
| chromosomes, human, 19-20 | The sixth of the seven groups of chromosomes containing two pairs conventionally named pairs 19 and 20. The chromosomes in this group, also called group f, are short and metacentric. (12 Dec 1998) |
| chromosomes, human, 21-22 | The seventh of the seven groups of chromosomes containing two pairs conventionally named pairs 21 and 22, and the y chromosome. The chromosomes in this group, also called the g group, are very short and acrocentric. (12 Dec 1998) |
| chromosomes, human, 4-5 | The second of the seven groups of chromosomes containing two pairs conventionally named pairs 4 and 5. The chromosomes in this group, also called group b, are large with centromeres in the submetacentric position. (12 Dec 1998) |
| chromosomes, human, 6-12 | The third of the seven groups of chromosomes containing seven pairs conventionally named pairs 6, 7, 8, 9, 10, 11, and 12, and the x chromosome. The chromosomes in this group, also called group c, are medium sized with centromeres in the submetacentric position. The x chromosome most resembles 6. This group presents the major difficulty in the identification of individual chromosomes. (12 Dec 1998) |
| chromosomes, human, pair 1 | One of the three pairs in the first group (or group a) of human chromosomes according to the current classification for humans. (12 Dec 1998) |
| chromosomes, human, pair 10 | One of the seven pairs in the third group (or group c) of human chromosomes according to the current classification for humans. (12 Dec 1998) |
| chromosomes, human, pair 11 | One of the seven pairs in the third group (or group c) of human chromosomes according to the current classification for humans. (12 Dec 1998) |
| chromosomes, human, pair 12 | One of the seven pairs in the third group (or group c) of human chromosomes according to the current classification for humans. (12 Dec 1998) |
| chromosomes, human, pair 13 | One of three pairs in the fourth group (or group d) of human chromosomes according to the current classification for humans. (12 Dec 1998) |
| chromosomes, human, pair 14 | One of three pairs in the fourth group (or group d) of human chromosomes according to the current classification for humans. (12 Dec 1998) |