Answer:
C. They are made from many carbon atoms
Explanation:
* More than 40 proteins and glycoproteins involved in the complement system are synthesized by the liver, macrophages, epithelial cells, they are present in the blood in plasmatic form, membrane, some have an enzymatic activity, regulator or membrane receptorThese are elements of the humoral innate immune response, they fight infections, purify immune complexes and apoptotic bodies.
<span>There are indeed three ways to activate the complement:</span>
Classical pathway: Activated by Immunoglobulins in immune complexes, aggregated Immunoglobulins, DNA, CRP, apoptotic bodies .......it involves nine fractions, starting with C1, then C4, C2, C3, to form a classical C5 convertase, then, activation of C5, C6, C7, C8, C9.
Alternative pathway: activated by polysaccharides (bacterial endotoxin), vascular wall poor in sialic acid, aggregated IgE ...C3b like is the first component in the alternate channel cascade, it will create an amplification loop, and form an alternative C5 convertase.
Lecithin pathway: Activated by mannose, fucose (carbohydrate of microorganisms)The first component is the complex MBL / MASP1 / MASP2: "mannose-binding protein": works according to the same principle as the complex C1 of the classical way (MASP2 cleaves the C4 and the rest of the cascade is equivalent to that of the classical way).
the three ways have the same outcome: A C5 convertase (formed by one of the pathways) cleaves C5 into C5a and C5b: C5b is deposited far from other fractions on the antigenic surface. The fixation of C5b in the cell is followed by that of C6, C7, C8, and C9 (9 molecules of C9): formation of the membrane attack complex (MAC) ==> Death of the cell by osmotic shock
Parathyroid hormones (PTH) increases the Ca++ concentration and slightly decreases phosphate ion concentration in the blood.
When Parathyroid hormone increases, the body release more calcium from bones into blood which lead to the increase in calcium concentration in the blood.
The parathyroid hormone increase in the other hand led to slightl
y decrease in phosphate ions since it reduces the reabsorption of phosphate from proximal tubule of the kidney
<span>Atoms that have filled outermost energy levels and do not participate in chemical bonding are called Inert Atoms. Remember this by thinking of the definition of Inert; meaning unable or not having the strength to move. So if it an atom has a filled outer level the electrons will be inert.
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