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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Well since the population just keeps growing and nobody migrates the organisms in the ecosystem will compete for food and other resources
Answer:
C) Both are waves of energy, but ultraviolet waves cannot be seen.
Explanation:
Both visible light and ultraviolet are two manifestations of the same thing: electromagnetic radiation (which is, basically, energy in one of its forms). They both travel empty space as waves, but visible light has a longer wavelength, which means that the distance between succesive peaks of the wave is larger than that of ultraviolet radiation. Visible light just happens to have a wavelength in the range our eyes are capable of seeing, but ultraviolet has a shorter wavelength than that, therefore we cannot see it.
B. Weighing , because all its checking is the weight.
