Answer: silent mutation: a nucleotide base in a codon is replaced with a different base BUT the resulting amino acid isn’t affected.
Missense mutation: similar to a silent mutation, the only difference is that the switch of the nucleotide DOES result in a DIFFERENT amino acid
Nonsense mutation: a nucleotide base is changed, but that change results in a premature stop of translation
(Remember that after transcription, you are left with a strand of mRNA that Is then translated into a protein. The mRNA is read in increments of three nucleotide bases (A,U,G, or C) which is called a codon. That codon makes a single amino acid, and a strand of amino acids makes a protein)
Answer:
we itch reacting to stimuli like when ee get poked we react and so on. And it not an evolution
Answer:
The fewer number of T cells a person has, the more chances to be affected by an opportunistic infection. When the number of T cells reaches 200 cells/µl, the person is at risk of being infected by other infections.
Explanation:
The whole immune system of a person who is infected with HIV infection seems to be severely affected. When the person is not treated or the disease is in a very advanced stage, the depletion of the T- cells turns to be very sharped, especially CD4+ T cells. At this point, the immune system can not resist the attack of other microorganisms. The <em>lower is the number of CD4+ T Cells, the higher possibility the person has to be attacked by opportunistic infections. </em>
Classically, it has been suggested that opportunistic infections appear after the CD4 + T lymphocytes reach very low levels, such as 200 cells/µl. The number of circulating T cells can be used as an indicator and a measure of global "immune competence", and the previously mentioned amount of CD4 + T cells is an accepted universal reference used to predict the risk of having one of these opportunistic infections.
Answer:
Humans impact the physical environment in many ways: overpopulation, pollution, burning fossil fuels, and deforestation. Changes like these have triggered climate change, soil erosion, poor air quality, and undrinkable water.
