Excess lead in the blood deranges the structure of red blood cell membranes, making them leaky and fragile. a. true b. false

The answer would be: a. True 

Lead cannot be degraded by human body so it will easily be accumulated. It can disrupt the structure of the cells and make their membrane fragile. This might cause the cell to lysis. It will also make the white blood cells to produce more inflammatory protein and linked to asthma in children.

The answer your looking for is a food chain grid. it describes how nature can support itself and survival of the fittest comes into play..

Humans can affect weathering and erosion in several ways.  humans cause  increases in acid rain and pollution, which increase the amount of  weathering  agents in the air and water, and then on land.for an easy answer: 1) acid rain2) pollution