An increasingly popular mechanism of gene knockout in bacterial cells is to use the crispr/cas9 system. the system uses a single-guide rna (sgrna) to direct the crispr associated protein 9 (cas9) endonuclease enzyme to a gene of interest. here, the cas9 protein will create a blunt, double-stranded break in the dna. the cas9 protein simply cuts, however, and does not directly cause a mutation to occur. by what mechanism does this system cause mutations?

CRISPR-Cas9 editing has offered a breakthrough in the world of science. Various scientists are interested in this and have effectively utilized this technique in editing DNA. The application of guide RNA is not novel, however, its process of mediating caspases towards the target sequences is a tremendous achievement.  

Though the mutations are reported, however, they are not reproducible yet. The mechanisms of DNA mutations through CRISPR-Cas have not demonstrated any kind of solid pathway, although it is reported to result in single base pair deletions in DNA distant from its activity site resulting in gene impairment.  

After the application of CRISPR for editing DNA, large mutations were witnessed in the sequences of DNA, that is, thousand-kilo base away from its site of activity. However, no experimental data offering the precise mechanism is available yet.  

answer-

the statement that f(x) = |x+a| + b has exactly one x-intercept is sometimes correct.

solution-

it solely depends on b, whether the function will have one or two or zero x intercept.

this plot of the given function, f(x) = |x+a| + b will be the basic absolute value graph i.e v shape, with vertex translated to (-a, b), instead of origin.

1-   if b is zero, the graph will have exactly one x-intercept, at x= -a

2- if b is positive, the whole graph will be above the x-axis, hence it will have no x-intercepts.

3- if b is negative, the graph will be below the x-axis, hence it will have two x-intercepts.

∴ the statement is sometimes true.