Explain the differences between chromosome painting and the older, more traditional method of staining chromosomes being prepared for karyotyping. Highlight the way in which each method identifies chromosomes by the unique sequences they contain
What will be an ideal response?
Chromosome painting relies on the specificity of DNA complementarity. Because unique sequences for each chromosome are known, short DNA molecules matching a set of these sites can be designed for each chromosome. Each set is labeled with a specific combination of fluorescent dyes and then allowed to hybridize (form base pairs) with the two homologous chromosomes that contain the unique sequences being targeted.
Giemsa stain is a nonfluorescent dye that has a high affinity for DNA, and specifically accumulates in regions that are rich in A-T nucleotide pairs. This dye produces a pattern of dark and light bands, which differ for each chromosome on the basis of the distribution of AT-rich regions.
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There are how many different kinds of RNA
codons? a. 3 b. 12 c. 28 d. 64 e. 120
In Experimental Condition 2 of the accompanying figure, the distribution of Chthamalus suggests that:a
interspecific competition kept Chthamalus from extending lower into the intertidal area. b. intraspecific competition kept Chthamalus from extending lower into the intertidal area. c. a limiting factor kept Chthamalus from extending lower into the intertidal area. d. a barnacle parasite kept Chthamalus from extending lower into the intertidal area. e. predation kept Chthamalus from extending lower into the intertidal area.
The cellular basis for bacterial resistance to antimicrobics include
A. synthesis of enzymes that alter drug structure. B. prevention of drug entry into the cell. C. alteration of drug receptors on cell targets. D. bacterial chromosomal mutations. E. All of these choices are correct.
Which of the following would be an example of an adaptation for seed dispersal?
A) pinecones B) nectar production C) deciduous cycles D) phototropism E) seeds wrapped in burrs