Bio Concepts:Sec Three

Osmosis

ajenkin2 — Thu, 23 Oct 2008 19:55:43 +0000

http://www.youtube.com/watch?v=qKq3hOgC8YE&NR=1

Osmosis is an increase in entropy, or diffusion, of water through a (semi)permeable membrane.

In the presented clip is part of the cartoon movie Osmosis Jones.The basic plot is as follows:

Frank Detomello catches a cold. The inside of his body is known as the “City of Frank” to its inhabitants, two of which - white blood cell cop Osmosis Jones, and cold tablet Drixorial - team up to fight the invading viruses intent on taking over the City.

Anyways, this movie is especially comical, and introduces children to the body and the process of osmosis and ‘virus protection.’ On the otherhand, osmosis is depicted as a ’super power’ so to speak, and is not explained in an intricate or even simple fashion, but more or less implied.

Evolution:Darwinism and Homosexuality

ajenkin2 — Fri, 10 Oct 2008 03:29:21 +0000

Through evolution, the human species have survived and became more complex and stronger, while other species have not, suggesting the process of natural selection. However, within the recent centuries, a new trait among humans has become known: homosexuality. Theoretically, if heterosexual humans are better survivors than homosexual humans, then will they eventually be naturally selected out of the human species? Is homosexuality bad based on the Darwin’s theory of natural selection? Throughout the world, there are many outlooks upon homosexuality. Some scientists claim that it is caused by the presence of a certain genotype known as Genotype G. It is frequently detected in homosexual men who may suffer from immune suppression caused by infection or human immunodeficiency virus. This genotype possesses two nonsense mutations in the pre-core region (“Critical Role”). Scientists have also found “that an area in the hypothalamus which influences sexuality, the interstitial nuclei of the anterior hypothalamus (INAH), was more than twice as large in heterosexual as in homosexual men-and these brain cells were completely absent in one of the gay males” (Bergman).This experimentation further concluded that the area in gay men was very similar to the women. In later trials there were further indications that the same part of the hypothalamus with certain lesions, in male primates lost interest in females. On the other hand, there are also scientists that believe homosexuality originates in the fetus.

‘… [T]he concentration of the hormone testosterone in the bloodstream of the developing fetus influences the sexual orientation and sex-typical behavior of the resulting adult. This hormone is produced mainly by Leydig cells which differentiate in the testes of the male embryos. In addition to testes in males, any fetus has two other sources of testosterone…In the brain, testosterone is metabolized to another hormone, estradiol, which during the fourth and fifth months of gestation stimulates the proliferation of nerve cells in the pre-optic nucleus of the hypothalamus….there are twice as many nerve cell bodies in the pre-optic nuclei [the INAH 2 and 3] of typical men compared to typical women. By a means yet to be discovered, individuals with these enlarged pre-optic areas, including most men, tend to prefer women sex partners.

Thus, sexual orientation somehow derives from the prenatal concentration of testosterone — lowering it in a fetal male affects his pre-optic nucleus and later, when he matures, his sexual orientation….estradiol affects at least two other areas of the hypothalamus: the anterior nucleus, which organizes sex-typical behavior and the ventromedial nucleus, which is blocked by the higher levels of estradiol in typical males but at lower levels (e.g., in typical females or some male homosexuals) organizes the timing of the “ovulatory” cycle. At least in these three areas of the hypothalamus the brains of typical men and typical women are different.’

Sources:

Bergman, Jerry. “Creationism and the Problem of Homosexual Behaviour.” April 1995. 11 April 2008. < http://www.answersingenesis.org/tj/v9/i1/homosexual.asp>.

“Critical Role of the 36-Nucleotide.” Journal of Virology. Sept.2007. 11April 2008. < http://jvi.asm.org/cgi/content/full/81/1…;.

Genetics:DNA Cloning

ajenkin2 — Thu, 18 Sep 2008 01:23:06 +0000

Genetics is study and science of heredity and genetic variation in living organisms. DNA is a protein that is encoded with particular inforamtion to pass on from generation to generation. Whne these are mixed together one gets the practice of DNA cloning. This is a process that works in effort to reproduce DNA fragments. There are multiple steps to take in this process: DNA recombination; transformation; and selective amplification. DNA recombination is the simple process of placing a DNA fragment into a vector, which is basically a host containing an anitbiotic-resistance gene. From there the recombinant vector is placed into an e. coli cell treated with CCl(2), thus they can then be proliferated throught selective amplification, or reproduced in a selective manner. The cells without the vectors in it die out. This allows certain DNA fragments to be reprocude in a bulk.

Cited Source: http://www.web-books.com/MoBio/Free/Ch9A.htm

Bio Princ. Carbohydrates

ajenkin2 — Sun, 07 Sep 2008 15:50:32 +0000

This is a “quality” Seaco-Chicken Sandwich covered in honey mustard! One may indulge in such a sandwich to satisfy ones hunger; in doing so they are taking in carbohydrates through starch, sugar (saccharide), and fiber. Once carbohydrates are taken in, then the body then breaks down the carbohydrates into glucose or multiple types of monosaccharide, which then may enter the bloodstream or be turned into energy or stored as fat for the body to use later. This sandwich looks like a great source of carbohydrates. If the bread was in fact whole grain it would be an even better source, however considering that it is white bread, the carbohydrates are easily digested.

Source:

(http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/carbohydrates-full-story/index.html)