Allele frequency refers to how common an allele is in a population. It is determined by counting how many times the allele appears in the population then dividing by the total number of copies of the gene. The gene pool of a population consists of all the copies of all the genes in that population.
Answer:
CRISPR Used To Edit Genes Inside A Patient With A Rare Form Of Blindness
and what CRISPR is is s a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea.[2] These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. They are used to detect and destroy DNA from similar bacteriophages during subsequent infections. Hence these sequences play a key role in the antiviral (i.e. anti-phage) defense system of prokaryotes.[2]
Diagram of the CRISPR prokaryotic antiviral defense mechanism[3]
The CRISPR-Cas system is a prokaryotic immune system that confers resistance to foreign genetic elements such as those present within plasmids and phages[4][5][6] and provides a form of acquired immunity. RNA harboring the spacer sequence helps Cas (CRISPR-associated) proteins recognize and cut foreign pathogenic DNA. Other RNA-guided Cas proteins cut foreign RNA.[7] CRISPR are found in approximately 50% of sequenced bacterial genomes and nearly 90% of sequenced archaea.
Explanation:
The answer is D, all the time
Electron microscope is used to see nucleus of a cell clearly