<span>It is well known that the centrosome acts as a microtubule organizing center, with its textbook role in forming mitotic spindles in dividing cells. So in many cells, the centrosome with its centrioles is indeed essential to ensure correct cell division, and in these the PCM ensures the distribution of the right number of centrioles to each daughter cell. But there are exceptions – which include somatic cells in fruit flies and some fungi – where no centrioles are needed; and centrosomes in some differentiated cells, including neurons and muscle cells, are inactive.</span>
Typhoid fever is most common in non-industrialized countries. Travelers to Asia, Africa, Eastern Europe, and Latin America are especially at risk. Salmonella typhi bacteria are shed in the urine or stool of infected persons, including chronic carriers. There are no known animal reservoirs for typhoid fever.
Answer:
Because the promoter region is initiation sites for transcription to occur.
Explanation:
Transcription is the first process of gene expression in both eukaryotic and prokaryotic cells. Transcription involves the synthesis of a complementary RNA strand from a DNA template. It is carried out by an enzyme called RNA polymerase which binds to the DNA molecule and adds nucleotides based on the sequence it reads on the DNA.
On the DNA molecule, are sequences of nucleotides which the RNA polymerase recognizes and binds to in order for the transcriptional process to start. These sequences are called PROMOTER regions. They are located upstream i.e. after initiation site, of the DNA. Without these promoter region, RNA polymerase cannot bind to the DNA molecule and hence transcription cannot occur.
Transfer because RNA stands for Ribonucleic Acid and in this you would transfer it.
