Answer:
CRISPR-Cas9 is a DNA modification technique derived from a bacterial defense mechanism.
This breakthrough innovation allows the deletion and insertion of genes in a simple, fast and efficient way, much like "DNA scissors".
The CRISPR-Cas9 method is increasingly used in laboratories because it has several advantages over the DNA cutting enzymes developed before it.
First advantage, it is much easier to use (compared to other gene-editing tools). It has already allowed several teams of researchers to target several genes at once, including in human cells.
Other major advantages resulting from the simplicity of the system: its speed and its low cost. The CRISPR-Cas9 method takes only a few days (instead of a few months) and is at least ten times less expensive than those used before.
CRISPR-Cas9 is therefore a tool of disconcerting ease to modify the genome of many types of cells (to produce a protein for example), in bacteria, plants, animals and perhaps one day in humans.
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>
Exocrine glands are the name of the gland that transports secretions through ducts
False- interneurons pass electrical impulses from a sensory neuron to a motor neuron (it connects these neurons)
Onion is an underground crop and it have no involvement in the photosynthesis. So it have no chloroplast in their cell.
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-Payshence
