<span>3,3',5,5'-Tetramethylbenzidine or TMB is a chromogenic substrate visualising reagent used in enzyme-linked immunosorbent assays (ELISA), it yields a blue color when oxidized, typically as a result of oxygen radicals produced by the hydrolysis of hydrogen peroxide by HRP, (thermofisher). The expected colorimetric result from the negative control in your assay will be no development of blue color</span>
Correct answer: D). The organism is buried in sediment and then dissolved by underground water
Mold is a copy of an organism, it is formed like the first layer of sediments harden and forms a mold. Then after that new layer of sediment fills and become hardens.
The fossil is left behind in sediment, which removes the remains of an organism from its surrounding material. The groundwater along with its mineral content dissolves the organic matter to form the fossil.
The second line of defense is nonspecific resistance that destroys invaders in a generalized way without targeting specific individuals: Phagocytic cells ingest and destroy all microbes that pass into body tissues. For example macrophages are cells derived from monocytes.
One example of a positive feedback loop in childbirth is contractions. When the contractions start, they produce oxytocin, which stimulates stronger contractions, which produce more oxytocin.
