All blood leaving the digestive system is routed directly to the , which gets a "first pass" at taking nutrients out of the blood and chemically altering them before sending out for other organs to use.

1. in what ways have non-native species been beneficial? 2. what are some of the hypotheses for the collapse of honeybee colonies? 3. distinguish between regional and functional extinction. 4. why is it difficult to measure background extinction rates? 5. what three factors are most important in causing extinction rates to climb?

Why is it bad that some cancer cells can make their own growth hormones?

All of the following statements about enzymes are correct except: proteolytic enzymes are also known as proteases. pectin methyl esterase causes browning of cut fruit. cloud loss in orange juice is due to enzyme activity. proteolytic enzymes in fish cause tissue softening during storage.