Answer:
Explanation:
This is because sickle cell disease is common in malaria dorminated area because their traits confers resistance to malaria. The red blood cells, which contain abnormal hemoglobin become sickle in shape after it has been affected by malaria parasite. Therefore, most American that have African ancestry are at high risk of
the disease because the African ancestry are carriers if this gene and are inherited by the Americans.
The answer is A. There was more energy escaping into space than being trapped by the atmosphere
Answer:
Statement C is the only one that is necessarily true for exons 2 and 3. It is also true for exons 7 and 8. While statements A and B could be true, they don’thave to be. Because the protein sequence is the same in segments of the mRNA that correspond to exons 1 and 10, neither choice of alternative exons (2 versus 3, or 7 versus 8) can alter the reading frame. To maintain the normal reading frame—whatever that is—the alternative exons must have a number of nucleotides that when divided by 3 (the number of nucleotides in a codon) give the same remainder. Since the sequence of the a-tropomyosin gene is known, it is possible to check to see the actual state of affairs. Exons 2 and 3 both contain the same number of nucleotides, 126, which is divisible by 3 with no remainder.
Answer: Then the longer it is, the more it protects against degradation. Proteins that are needed over a long period of time come from a long tailed mRNA.
Explanation:
Messenger RNA (mRNA) is the ribonucleic acid that transfers the genetic code from the DNA of the cell nucleus to a ribosome in the cytoplasm. It determines the order in which the amino acids in a protein will bind and acts as a template or pattern for the synthesis of that protein.
Messenger RNA is synthesized in the cell nucleus in eukaryotes from the process called DNA transcription.
<u> In most cases, once this messenger RNA has been synthesized, it must be matured (RNA maturation)</u>. This involves the removal of intercalary sequences called non-coding introns from the protein to be synthesized. Then, the addition of a structure called CAP to the 5' end, which is a modified guanine nucleotide needed for the normal process of DNA transplantation and maintaining its stability. This is critical for proper recognition and access of the ribosome. Also, polyadenylation which is the addition of the sequence called Poly-A to the 3' end. The Poly-A sequence is made up of several adenine molecules and is located at about 20-30 bp towards the tail (AAPAA sequence) or polyadenylation signal, which protects the end of the mRNA. The polyadenylation helps to increase the period of the message, so that the transcription lasts longer in the cell and therefore more protein is translated and produced.
This mature messenger RNA is transferred to the cell's cytoplasm, in the case of eukaryotes, through pores in the nuclear membrane. The messenger RNA in the cytoplasm is coupled to the ribosomes, which are the machinery in charge of protein synthesis.<u> However, after a certain amount of time the mRNA is degraded</u> into its component nucleotides, usually with the help of ribonucleases. So, an mRNA with a short tail will have a shorter lifespan.
Then, proteins that are needed over a long period of time come from a long tailed mRNA. And proteins that are briefly nedded come from a short tailed mRNA. This is because, as explained, the Poly-A tail serves to protect the mRNA molecule from degradation. So, then the longer it is, the more it protects against degradation.
