Lactose Intolerance in Humans Is the Inability to Digest a Specific

question 38

Multiple Choice

Lactose intolerance in humans is the inability to digest a specific sugar found in milk and some milk-derived dairy products. This milk sugar is called lactose, and it is broken down into two simple sugars, glucose and galactose, by the enzyme lactase. Symptoms of this disease, which occur after a person consumes significant amounts of lactose, include abdominal bloating and cramps as well as diarrhea and nausea. Many mammalian species become lactose intolerant shortly after weaning. At this time, the gene that produces lactase becomes inactive so that the enzyme is no longer produced. However, some human populations (approximately 25 percent of all adults) have developed lactase persistence, in which lactase is continually produced throughout adulthood. Which of the following human populations likely evolved lactase persistence?

• A) populations living on islands
• B) populations in which milk is a component of the diet throughout an individual's life
• C) populations in which milk-derived products are essential for young individuals
• D) Lactase persistence will evolve in any population that has a strong need for digesting milk.

---

Definitions:

Cross-Footing

A bookkeeping process that involves checking the mathematical accuracy of figures in financial statements by ensuring that sums of columns and rows respectively match.

Cash Receipts Journal

A specialized accounting journal used to record all receipts of cash.

Equality

In financial terms, refers to the state where two values, amounts, or figures are of the same value or balance each other out.

One-Column Purchases Journal

A simplified accounting ledger that records only the purchases of goods and services in a single column, typically for small businesses or specific types of transactions.