Answer: A. 7 protons
Explanation: Just count the number of P's to get your neutrons.
Humans have caused quokka populations to decrease due to animal cruelty. Humans have also introduced predators to quokkas, such as dogs and cats.
Hope this helped!
Answer:
b. A second marker in the knock-out cassette, that if inserted into the genome results in cell death when plated on selective media.
Explanation:
General recombination, also known as homologous recombination, refers to the naturally occurring process of exchange of genetic material between pairs of homologous DNA sequences. This process (homologous recombination) can be exploited by genetic engineering to insert DNA segments of interest at target genes. Moreover, a cassette is a mobile DNA segment containing almost a gene and a recombination site, which is integrated into the <em>locus</em>/<em>loci</em> of interest by homologous recombination. A cassette may contain a DNA segment called 'negative marker' which prevents growth under particular conditions, while a positive marker permits growth under certain conditions. In consequence, a second marker consisting of a drug cassette may be used as a negative marker in order to evidence its insertion by inducing cell death when they are plated in selective conditions.
