问题 选择题

下列不属于生物变异的是(  )

A.玉米果穗的颜色上的差异

B.安康羊的后代比其父母矮许多

C.红眼果蝇与白眼果蝇的头部

D.未成熟的小苹果与成熟的大苹果

答案

遗传是指亲子间的相似性,变异是指亲子间和子代个体间的差异.

A、玉米果穗的颜色上的差异是变异.

B、安康羊的后代比其父母矮许多是变异.

C、红眼果蝇与白眼果蝇的头部属于变异.

D、未成熟的小苹果与成熟的大苹果不属于变异.

故选:D

单项选择题
阅读理解

Dieters' who eat meals high in protein might lose a bit more weight than those who get less protein and more carbohydrates (碳水化合物)一all other things being equal, a new analysis of past studies suggests. Researchers found that over an average of 12 weeks, people having a high一protein diet lost about 1.8 extra pounds, and more body fat, than those having a standard-protein diet.

Wycherley from the University of South" Australia in Adelaide, the lead author on the study says it’s possible that the body may spend more energy and bum more calories while dealing with protein, compared to carbohydrates. Another explanation for the link his team observed is that eating protein helps preserve muscle mass and muscle mass bums more calories, even when the body is resting, than other types of mass. He says people in the studies tend to get protein from a variety of animal and vegetable sources. Vegetable sources of protein include beans.

It is not obvious why a higher protein-to-carbohydrate ratio might help people lose more pounds——and one obesity researcher not involved in the new analysis questioned whether the trials were strong enough to make that conclusion. “The studies are generally far too short to tell effect,” Dr. James Levine from the Mayo Clinic in Scottsdale, Arizona, told Reuters Health in an e-mail. But given the limitations of the present evidence, Levine said, “It makes no real difference which of the weight-loss ways one chooses.”

小题1:According to Wycherley’s analysis, dieters should take in more ______.

A.fat

B.carbohydrates

C.protein

D.calories小题2:What can we learn from the studies?

A.It bums more calories to deal with carbohydrates.

B.Protein helps keep muscle mass which bums calories.

C.Vegetables contain more protein than animals.

D.No more calories are burned while the body is resting.小题3:What is Levine’s attitude towards the conclusion of the studies?

A.Doubtful.

B.Supportive.

C.Curious.

D.Agreeable.