Answer:
Negative feedback loop
Explanation:
When the blood calcium level is low, the receptors of the parathyroid gland sense it and increase the production of cAMP. The increased cAMP levels stimulate the secretion and release of parathyroid hormone from the parathyroid gland into the blood.
The increased parathyroid hormone levels stimulate the number and activity of osteoclasts and speed up the process of bone resorption resulting in the release of calcium ions from bone into the blood to raise the blood calcium levels.
Here, the response (increased blood calcium level) reverse the stimulate and hence, the process is under the regulation of negative feedback loop
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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.
<span>Lysis of adhesions is performed on either the Fallopian tubes or the ovaries. </span>
Answer:
375 million-year-old fish, a large scaly creature not seen before, that they say is a long-sought "missing link" in the evolution of some fishes from water to a life walking on four limbs on land.
In addition to confirming elements of a major transition in evolution, the fossils are widely seen by scientists as a powerful rebuttal to religious
Explanation:
on closer examination, scientists found telling anatomical traits of a transitional creature, a fish that is still a fish but exhibiting changes that anticipate the emergence of land animals — a predecessor thus of amphibians, reptiles and dinosaurs, mammals and eventually humans
The answer is: Create a diagram that hypothesizes ancestry.
