Weak bases, just like weak acids, dissociate slowly when dissolved with water. An Arrhenius acid is any substance that ionizes when it dissolves in water to give the H+, or hydrogen, ion. An Arrhenius base is any substance that gives the OH-, or hydroxide, ion when it dissolves in water.
Start with your producers, or plants (grasses, flowers, etc.). Then your 1st level consumers (herbivores), like grasshoppers, mice, etc. Then your second level producers (carnivores and omnivores) that eat the herbivores (like birds). And keep going, knowing each of the levels get eaten by each other. 10% of energy is transferred in each level. An example might be...
Grass > Mice > Hawk > Vulture
<span>a morbidity survey of the general population, like the national health interview survey</span>
