bicarbonate can act as an acid or a base (i.e., donate or accept hydrogen ions) depending on conditions.
Under present-day conditions, these reactions buffer the pH of surface seawater at a slightly basic value of about 8.1 (above the neutral value around 7.0). At this pH, the total dissolved inorganic carbon (DIC ~ 2 mM) consists of approximately 1% CO2, 90% HCO3–, and 9% CO32– (Figure 2.1). The total boric acid concentration (B(OH)4– + B(OH)3)) is about 1/5 that of DIC. As discussed in section 2.2, increases in CO2 will increase the H+concentration, thus decreasing pH; the opposite occurs when CO2 decreases. We note that isotope fractionation between B(OH)3 and B(OH)4–is used for estimating past pH values
Fossil Record and characteristics of today's chordates
Answer:
mantle
Explanation:
Convection currents in the Earth occur in the mantle. The core of the Earth is extremely hot, and material in the mantle close to the core is heated..
Enzyme function is influenced by physical and chemical environment factors such as pH and temperature.
-Enzymes may require a nonprotein cofactor or ion for catalysis to take place.
-Enzymes increase the rate of chemical reaction by lowering activation energy barriers.