Answer:
These are the Reticular Activating system
Explanation:
These are network of neurons that occupy lager areas of the brainstem. They are located between the brain stem and the cortex.These neurons projected anteriorly into the hypothalamus, posteriorly into the thalamus to form the ascending RAS and emerged directly into the cortex.
Generally,the RAS is made up of 4 components.These are each made up of group of nuclei .The latter are simultaneously activated by the lateral hypothalamus,which cause the release of neurotransmitters that cause the modulatory effects produced by the entire RAS
Their major function is the control of sleepiness and wakefulness in individuals.It does this with the interactions with a lot of neurotransmitters present in the brain.
Besides the above functions the RAS is also responsible for the control of focus, stability of muscles tone.
Answer:
HeLa cells contain rare traits that make them invaluable to scientific research. Research into the Lacks family may provide insight into this mutation and cell proliferation.
Explanation:
HeLa cells have a controversial origin, rooted in ethical breaches. They were derived from a non-consenting, female African-American donor patient, Henrietta Lacks who was terminally ill with a form of cervical cancer. These particular cells have a remarkably short period of proliferation, due to their active telomerase.
During cell division, these telomoerases were found to make repeat copies of the cell's telomere, and the cells can divide an unlimited number of times in lab cell cultures- a very rare occurrence. They were later commercialized- HeLa cells are durable, robust and commonly used in cancer cell research.
The terms chromosome and gene were used long before biologists really understood what these structures were. When the Austrian monk and biologist Gregor Mendel (1822–1884) developed the basic ideas of heredity, he assumed that genetic traits were somehow transmitted from parents to offspring in some kind of tiny "package." That package was later given the name "gene." When the term was first suggested, no one had any idea as to what a gene might look like. The term was used simply to convey the idea that traits are transmitted from one generation to the next in certain discrete units.
Magnification of chromosome 17, which carries the breast and ovarian cancer gene. (Reproduced by permission ofCustom Medical Stock Photo, Inc.)
The term "chromosome" was first suggested in 1888 by the German anatomist Heinrich Wilhelm Gottfried von Waldeyer-Hartz (1836–1921). Waldeyer-Hartz used the term to describe certain structures that form during the process of cell division (reproduction).
One of the greatest breakthroughs in the history of biology occurred in 1953 when American biologist James Watson (1928– ) and English chemist Francis Crick (1916– ) discovered the chemical structure of a class of compounds known as deoxyribonucleic acids (DNA). The Watson and Crick discovery made it possible to express biological concepts (such as the gene) and structures (such as the chromosome) in concrete chemical terms.
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Read more: <span>http://www.scienceclarified.com/Ca-Ch/Chromosome.html#ixzz57wQgdEzZ</span></span>
This is called Bacterial Transformation.
False; Melanin absorbs and dissipates the harmful UV rays that can damage the DNA of your skin cells. Keratin is a fibrous protein that helps to protect skin from abrasion.
