1. (2023高三上·川汇开学考)  阅读理解

On the "healthy" section of any breakfast menu, you're bound to spot an egg white omelet (煎蛋卷). With no fat and just a quarter of the calories in a whole egg, the whites look like the best choice at first glance. Not so fast, though new research shows a good reason why you might want to keep the yolk (蛋黄) in if you want to get fit. Plus, forget the bad impression that the cholesterol (胆固醇) in yolks has gotten in the past. The USDA removed limits on dietary cholesterol in its most recent dietary guidelines. It's all because evidence doesn't back up claims that the cholesterol you eat has much influence on blood cholesterol levels.

In a recent study, researchers had ten young men eat either whole eggs or egg whites after completing a strength-training workout. Both egg choices contained 18 grams of protein, and the eggs were developed with chemical markers. Thanks to them, the researchers tracked how the men's bodies used amino acids (氨基酸) from the eggs and egg whites, and found some surprising results. About 65 to 70 percent of amino acids were available in the blood for both the whole egg and egg white groups suggesting they'd be equally useful in building muscles. But the rest of the results didn't back up that conclusion.

When the researchers looked specifically at how much protein synthesis — the process that helps muscles repair and grow — occurred, one form of egg clearly did better than the other. "Having whole eggs immediately after exercise resulted in greater protein synthesis than just having egg whites," says lead study author Nicholas Burdin a statement.

Although this study was too small I to be conclusive, its conclusion backs up whole egg benefits that nutritionists have been praising for years. From their point of view egg whites are high-protein, low-calorie, but the yolk contains nearly all of an egg's vitamins. And one study found that adults who eat whole eggs in the morning lose more weight and body fat than those who get the same number of calories from a bread-based breakfast. While no large studies have looked into the weight-loss benefits of whole eggs vs egg whites, there's also no evidence that the 140 calories in two whole large eggs should scare you away. Crack on, egg lovers.

1. （1） What's implied in Paragraph 1?

   A . The whites can help people have a good shape. B . The yolk's function is different from the whites. C . People tend to consider the yolk to be unhealthy. D . The yolk has much to do with blood cholesterol levels.
3. （2） Why were the eggs developed with chemical markers?

   A . To help process the proteins better. B . To make them healthier for people. C . To track the amino acids during digestion. D . To help the body consume amino acids.
5. （3） The findings of the recent study mainly show that____. 

   A . amino acids are easy to get in eggs B . eating the whole egg helps build muscles C . the yolk of the egg is better than the white D . eggs can produce more proteins than any other kinds of food_________.
7. （4） What would be the best title for the text?

   A . Egg Whites VS Whole Eggs B . Egg White Omelets or Just the Yolk C . The Correct Way to Build Muscles D . Unknown Facts about Egg White Omelets