The human immunodeficiency virus (HIV) that causes the disease known as aids selectively infects helper T cells (CD4+).
This retrovirus also infects macrophages and dendritic cells. When CD4+ T cell numbers decrease below a critical level (due to the killing of this cells with different mechanisms), cell-mediated immunity is lost. As a result, the body becomes progressively more susceptible to infections, leading to the development of AIDS.
<span> HIV can be transmitted only via body fluids like blood, semen, pre-seminal fluid, rectal fluids, vaginal fluids, and breast milk, which means that people usually get or transmit HIV through sexual behaviours and use of the needle. For HIV infection, these fluids must come in direct contact with a mucous membrane or damaged tissue. Another way is to be directly injected into the bloodstream (from a needle for example).</span>
Answer:
Rex is not a Tyrannosaurus rex because each of his hands has three fingers. Tyrannosaurus had only two fingers on each hand.
Answer: She spun faster because her mass was closer to her center of rotation. The rate of spin increased to conserve angular momentum.
Explanation: plato answer
Polyploidy is the term that describes the chromosomal abnormality of having extra chromosomes.
