Answer:
In order to accurately evaluate progress in a flexibility workout regimen, it is important to establish a baseline level of flexibility and then to track progress during the regimen from that starting point. A baseline establishes where an individual is before starting a program; without a baseline, it would be difficult to know how much progress has been made as a result of the workout regimen. Tracking progress during a regimen is important because that information establishes the effectiveness of the regimen.
ATP-driven pumps will move Ca ++<span> out of the sarcoplasm back into the SR. This results in the “reshielding” of the </span>actin<span>-binding sites on the thin filaments. Without the ability to form cross-bridges between the thin and thick filaments, the </span>muscle<span>fiber loses its tension and relaxes.</span>
Answer:
Three different ways in which antiretroviral drugs can prevent the formation of new viruses are:
- Inhibiting the reverse transcriptase enzyme in both nucleoside analogues and non-nucleoside analogues.
- Enzymatic inhibition of integrase enzymes.
- Inhibiting entry by antagonizing CCR5 co-receptors.
Explanation:
Antiretroviral drugs are those used for the treatment of human immunodeficiency virus (HIV) infection, making the effect of the virus on the host cell is less and preventing the development of AIDS.
This type of drug has been classified, according to their mechanism of action, being grouped into several families of drugs. Three different ways by which antiretroviral drugs can prevent the formation of virus are:
- <em><u>Inhibition of reverse transcriptase enzyme</u></em><em>: this enzyme is a DNA polymerase capable of forming single strand viral RNA by a process that is reverse to normal DNA to RNA transcription. Its inhibition prevents the formation of viral particles in the host cell. They are divided into nucleoside analogs and non-nucleoside analogs.</em>
- <em><u>Enzymatic Inhibition of Integrase enzymes</u></em><em>: this type of enzyme is contained in the virus, and is capable of causing a retrotranscribed DNA to integrate into the host cell's DNA so that viral replication occurs. Its inhibition prevents the replication process.</em>
- <em><u>Entry inhibitors or antagonists CCR5 co-receptors</u></em><em>: CCr5 is a membrane protein, found on the surface of CD4 T lymphocytes, which facilitates the entry of the virus into the cell. The drug acts as a competitive inhibitor of the viral particle, preventing the entry and infection of the host cell.</em>
The most effective treatments against HIV infection involve the use of two or more types of antiretroviral drugs.
