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:
agricultural extension agent are train expert that acts as a middle man between the farmers and research institute or organisation. they are saddled with the responsibilities of bringing new innovations, technologies, knowledge e.t.c concerning agriculture to farmers and they in turn takes farmers concerns, complains and outcry to research institute.
they help to teach farmers on how too use modern farm tools and technologies. the extension agent use different methods to arouse or captivate the farmers and they are agent of change in that they help people form their own organizations in order to be able to tackle their problems.
they pass through different training and workshops and belong to a professional body before they can be certified an agricultural extension agent.Agricultural extension trainning/programmes cover a broad area including improved crop varieties, better livestock control, improved water management, and the control of weeds, pests or plant diseases. they are well paid and derive maximum satisfaction when helping farmers and proffering solutions to their problems.
Explanation:
Answer:
A
Explanation:
my was the same but A,B,C,D
Kelp --> sea urchins ---> sea otters best represents the feeding relationships in a kelp ecosystem that has not been disturbed
by humans.
