A blood alcohol concentration (BAC) or blood alcohol level (BAL) reflects the amount of alcohol in the body. Food, type and quantity of beverage, weight, sex, and rate of elimination determine the BAC after the consumption of alcohol.
The process of oxygen transfer in the gills of a fish is a good example of the benefits of countercurrent exchange. As oxygen poor blood meets an opposed flow of oxygen rich water, the oxygen begins to diffuse out of the water and into the blood stream.
Areas around large water bodies and thermal springs are generally free of permafrost because of increased heat flow in the ground (Figure 80). The permafrost table is the upper boundary of permanently frozen ground below the earth's surface. The area between it and the surface is called the suprapermafrost layer.That part of the suprapermafrost zone that freezes in winter and thaws in summer is considered the active layer.he thermal conductivity of silt is about one-half that of coarse-grained sediments and several times less than that of bare rock, which has a high reflectivity value. The active layer is thinnest and the permafrost layer generally thickest in fine-grained soils such as silt and clay.