- 行业: Education
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Founded in 1946, Palomar College is a public two-year community college in the city of San Marcos, located in north San Diego County, California. Palomar offers over 300 associate degree, certificate programs and is designated by the U.S. Department of Education as an Hispanic-Serving Institution ...
A gland surrounding the urethra at the base of the bladder. It secretes most of the seminal fluid that is expelled with sperm cells during ejaculation.
Industry:Anthropology
A date that gives the time of an event only with reference to another event that is not worldwide in scale. It only indicates that one event occurred earlier or later than another. For instance, the observation that strata 2 is younger than strata 1 beneath it in a geological deposit does not provide information about how many years ago strata 2 was laid down. It only indicates its age relative to strata 1. In addition to the use of stratigraphy, relative dating methods include biostratigraphy and fluorine analysis dating. See chronometric date.
Industry:Anthropology
A diagnostic procedure for pregnant women to determine whether or not their fetuses have gross chromosomal anomalies. It involves sampling the liquid immediately surrounding a fetus within the amnion. This amniotic fluid is extracted through the mother's abdominal and uterine walls with a hypodermic needle. The amniotic fluid mostly contains fetal urine but also has millions of fetal skin cells that can be cultured to produce a karyotype. There is 99+% accuracy in diagnosing Down syndrome and most other gross chromosomal aberrations including neural tube defects such as spina bifida.
Industry:Anthropology
A radiometric dating method based on the changing ratio of argon-40 to argon-39 with the passage of time in volcanic rock or ash. This technique was derived from potassium-argon dating. The argon-40/argon-39 method is usually more accurate than potassium-argon dating and doesn't require as large a sample.
Industry:Anthropology
A biological trait that has changed over time from the ancestral form and/or function that was present in the species from which it came.
Industry:Anthropology
A routine diagnostic procedure for pregnant women to determine whether or not their fetuses have gross chromosomal anomalies. This screening procedure is also called maternal serum alpha-feto protein (MSAFP) testing. The testing is comparatively inexpensive but not as reliable as amniocentesis or chorionic villi sampling. With AFP sampling, blood is drawn from a pregnant woman in order to determine the amount of alpha-feto protein that has leaked into her system from her unborn child. Unusually high or low amounts of AFP relative to the stage of pregnancy indicate that there may be specific kinds of genetic defects. Specifically, it may indicate the likelihood of Down syndrome, neural tube defects, abdominal wall defects, and trisomy 18. Low AFP levels are associated with Down syndrome, while high levels are indicative of neural tube defects. The amounts of other diagnostic fetal chemicals (hCG and estriol) also are measured in expanded AFP screening or triple-screening.
Industry:Anthropology
A relative dating method based on the association of early human sites with changing features of the land, such as the advance and retreat of glaciers or the rise and fall of sea levels. When these events are well dated, geochronology could be considered a reliable calibrated relative dating technique. Associated evidence may be changes in the frequency of plant species measured by pollen count and other kinds of paleoecology evidence.
Industry:Anthropology
A more or less distinct group of individuals within a species who are reproductively isolated from other groups. In other words, they restrict their mate selection to members of their own population. This is usually due to geographic and/or social barriers to mating with outsiders. Members of a completely isolated small population tend to have similar genetic characteristics due to generations of inbreeding.
Industry:Anthropology
A pneumonia-like accumulation of fluid and swelling in the lungs. Like cerebral edema, it can be caused by hypoxia at high altitude. While pulmonary edema is potentially life threatening, it generally is less likely than cerebral edema to result in death if treated in time.
Industry:Anthropology
A genetically inherited X-linked error in metabolism caused by an inadequate amount of the enzyme glucose-6-phosphate dehydrogenase in red blood cells. When exposed to certain environmental influences, such as fava beans and some drugs (sulphonamide antibiotics, some antimalarials including primaquine, and several other sulphur-containing drugs) , the red cells of individuals with this deficiency burst, resulting in severe anemia. As in the case of sickle-cell trait and thalassemia, this anemia may provide some immunity to falciparum malaria. G6PD deficiency is also known as "favism. " It is the most common type of human enzyme deficiency--about 400 million people have this condition around the world. It is a common problem especially in populations around the Mediterranean Basin, the Middle East, and Southeast Asia.
Industry:Anthropology
