An environmental scientist might study the effect of soil pollution on plant growth. This is true.
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Answer:
According to Dr. Ray Schiling (member of the American Academy of Anti-aging medicine) about 1.5 million people suffer from peanut allergies. The seeds of peanut (<em>Arachis hypogea</em>) contain an array of allergens that can induce the production of IgE specific antibodies predisposed individuals. Ara1 and Ara2 are most common seed storage protein that cause allergy. Other allergen proteins such as Ara3 to Ara 17 have also been identified that cause allergy.
Entry of peanut allergen into body
When peanut allergens enter the body of an individuals it leads to development of different symptoms like itchy skin, tingling sensation, nausea, runny nose and anaphylaxis.
Allergic response
There are two subsets of T-cells Th1 and Th2. Both invoke different response to allergens. Th1 direct a non-allergic response while Th2 direct allergic response ranging from releasing of histamine to anaphylactic response. The presence of IL-12 cytokines direct a Th1 based, nonspecific response.
Mechanism of allergic response (interaction between helper T cell and B cell)
Step 1.
When allergen enter to body they are encountered by B cells. Immunoglobulin receptors on the surface of B cells recognize antigen (Peanut allergens) and get attached, which are then internalized and processed. Within B cells the fragments of antigens combine with HLA class 2 proteins.
Step 2
HLA class 2 with antigen fragments (peanut allergens) then display on the surface of B cells.
Step 3
Receptors on the surface of helper T cells recognizes the complex of HLA class 2 and antigen fragments (peanut allergen) and is activated to produce cytokines, which activate the B cells.
Step 4
B cell is activated by cytokines and begins clonal expansion. Some of the progeny become anti-body producing plasma cells while other become memory B cells.
The idea that all living things are composed of cells and that all cells come from other cells defines the cell theory.
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Natural selection is nature’s way of keeping the best fit-to-live things alive, and so on continue to the next generations.
For example, if a rabbit has a limp, it is bound to be out run and eaten by a predator relatively early in its life (unless it is extremely lucky.) Because of this, it is unable to reproduce, and there genes that it contained to have its limp are unable to spread through inheritance. Natural selection goes both ways. For example, if a hawk has very god vision, it will be able to scope out its prey easily, so it will thrive. Therefore, when it produces offspring of its own, its trait of good eyesight will pass on to its offspring.
So, as enough time goes on, the bad traits will be weeded out and the good ones will remain.
Answer:
<h2>Frost is the decrease in air temperature to a value equal to or lower than the freezing point of water 0 ° C (WMO, 1992). The ice cover is one of its forms produced by the sublimation of water vapor on objects; it occurs when these temperatures are present (Ascaso and Casasls, 1986).</h2>
Explanation:
<h2>MEXICO ♥</h2>
