<span>Based on the
cladogram, mackerel has segmented body and jaws. They have vertical stripes on
their backs and fork tails. In addition, mackerel is a multicellular species of
pelagic fish, which were restricted in their distribution ranges and live in
separate populations.</span>
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.
The answer is approximately 42.57 kDa. The average weight of an amino acid is 110 Daltons. Therefore, a generic amino acid of 387 amino acids will have 110 *387 = 42570 Daltons. 1000 Daltons is equal to 1 kDal. Therefore 42570/1000 = 42.57 kDa
Answer: Option A. "tetracyclines"
Explanation:
Tetracyclines are defined as a group of broad-spectrum antibiotics that are either isolated directly from several species of Streptomyces bacteria or can be synthesised semi-synthetically.
Tetracyclines act as inhibitors of growth rather than killing the infectious agent. Tetracyclines passively diffuse through porin channels present in bacterial membrane. it reversibly bind to the bacterial 30S ribosomal subunit to inhibit protein synthesis and prevents the aminoacyl transfer ribonucleic acid (tRNA) from binding to A site of the ribosome.
Hence, it is proved that tetracyclines bind to 30s ribosomal subunit rather than 50S ribosomal subunit in the ribososmes.
