there aren't many enzymes in food, mainly in fruits, the enzymes in friuts are very similar to ptylin found in the mouth that help break down sugar, they do not need to be ingested before they activate, a proof of this is the apple test, buy an apple, take a bite and leave it without covering it for a few minutes, you'll notice that the bitten part starts turning yellowish brown because the enzymes in the apple are already breaking it down.
In summary, they do not need to be ingested before activation, and the major characteristic of an enzyme is that they do not change after they react with (breakdown) food, so they are in the same form before and after they finish breaking down the food.
Eventually, all of the energy that enters the ecosystem is lost in the form of heat.
One way is to share your problems with a friend or parent and tell them how you are feeling. Get plenty of sleep as well and eat healthy, avoid any alcohol and drugs. Hope this helped.
Answer:
The correct answers are A, B and D. The Clean Air Act was important because it emphasized cost-effective methods to protect the air; encouraged people to study the effects of dirty air on human health; and created a regulation that makes any activities that pollute the air illegal.
Explanation:
The Clean Air Act is a federal federal law designed to control air pollution nationwide. The Environmental Protection Agency (EPA) is required to develop and enforce the regulations to protect the general public from exposure to air pollutants that are known to be dangerous to human health. The 1963 law established a basic research program, which was expanded in 1967. The main changes to the law, which require regulatory controls of air pollution, were promulgated in 1970, 1977 and 1990.
The 1970 amendments significantly expanded the federal mandate by demanding broad federal and state regulations, both for fixed sources of pollution (industrial) and mobile sources.
In 1990 provisions were added to deal with acid rain, depletion of the ozone layer and toxic air pollution, and a program of national permits of fixed sources was established. Also new requirements were established for the reformulation of gasoline, the adjustment of Reid vapor pressure (RVP), which measures the volatility of gasoline; and the norms to control the evaporation emissions of the gasoline.
The Clean Air Act is important because it was the first important environmental law in the United States to include a disposition regarding citizen demands. Numerous local and state governments have promulgated similar laws, either the execution of federal programs or to fill important loopholes at the local level in federal programs.
The correct answer is: The recessive allele produces a phenotype that is better able to survive and reproduce than the dominant phenotype.
Natural selection (adaptation mechanism), gene flow, and mutation combine to change allele frequencies across generations. Natural selection tends to increase in frequency beneficial alleles, while it tends to decrease in frequency deleterious alleles.