Answer:
dies of a undignosed disease at age 7
Explanation:
A terminally ill 7-year-old girl — who two years ago received Christmas cards from well-wishers around the world — died Friday at her Sanpete County home of an undiagnosed disease that had caused her to stop growing at age 3.
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate properly during cell division. There are three forms of nondisjunction: failure of a pair of homologous chromosomes to separate in meiosis I, failure of sister chromatids to separate during meiosis II, and failure of sister chromatids to separate during mitosis.[1][2][3] Nondisjunction results in daughter cells with abnormal chromosome numbers (aneuploidy).
Calvin Bridges and Thomas Hunt Morgan are credited with discovering nondisjunction in Drosophila melanogaster sex chromosomes in the spring of 1910, while working in the Zoological Laboratory of Columbia University.[4]
completed question'
.....culturing viruses that requires a human host
Answer:
Diploid cell culture lines, developed from human embryos, are widely used for culturing viruses that require a human host
Explanation
Viruses can not thrive in a non-living host or artificial media.They are intracelular parasites which needed living host to replicate . Cultures lines from Human embryo in are therefore used for culturing viruses of human host, so that its mode of replication and gene expression can be studied, and therefore its virulence can easily be studied.
This method have the advantage that;
1.there is no need to make use of the whole animal rather,on a tiny tissue needed can be isolated for culture.
2. the cells growth is continuous,and can be preserved in liquid Nitrogen and renew for future culture
3. cells can be grown in different containers, with ability to decide the number of cells needed.
Temperature is kept at optimum for human in the culture at 37 degree centigrade, nutrients are provided, NaHC03 as buffers for C02, and the medium is humidified.
Answer:
Explanation: thank you!!!
<span>The atmosphere of Venus is mostly carbon dioxide, 96.5% by volume. Most of the remaining 3.5% is nitrogen. Early evidence pointed to the sulfuric acid content in theatmosphere, but we now know that that is a rather minor constituent of theatmosphere.
T</span>he atmosphere of Neptune consists mainly of hydrogen and helium, but about 2.5-3% of the atmosphere is methane. Like Uranus, clouds in Neptune's atmosphere<span> are composed of crystals of methane.</span>
