Breastfeeding can reduce rates of malnutrition and death in children.

A. 1.5m     B. 1.4m     C. 1.3m

B．unwise food selections

C．under-nutrition

D．both B and C

A、disadvantages

B、faults

C、deficiencies

D、delicacies

A、Protein folding is assisted by intervention of specialized auxiliary proteins called chaperone.

B、Protein folding tends to be modular, with areas of local secondary structure forming first, then coalescing into a molten globule.

C、Protein folding is driven first and foremost by the thermodynamics of the water molecules surrounding the nascent polypeptide.

D、The formation of S-S bond in a mature protein is facilitated by the enzyme protein disulfide isomerase.

E、Only a few unusual proteins, such as collagen, require posttranslational processing by partial proteolysis to attain their mature conformation.

Researchers from the London School of Hygiene & Tropical Medicine said consumers were paying higher prices for organic food because of its imagined health benefits, creating a global organic market worth an estimated $48 billion in 2007.

A systematic review of 162 scientific papers published in the scientific literature over the last 50 years, however, found there was no significant difference.

"A small number of differences in nutrient content were found to exist between organically and conventionally (通常) produced foodstuffs, but these have nothing to do with public health, " said Alan Dangour, one of the report's authors.

"Our review indicates that there is currently no evidence to support the selection of organically over conventionally produced foods on the basis of nutritional superiority . "

The results of research, which was commissioned by the British government's Food Standards Agency, were published in the American Journal of Clinical Nutrition.

Sales of organic food have fallen in some markets, including Britain, as a slowdown in economic growth has led consumers to cut back on purchases.

The Soil Association said that growth in sales of organic products in Britain slowed to just 1.7percent, well below the average annual growth rate of 26 percent over the last decade.

Why does organic food cost more than conventionally produced food？

A．Because people think they are much healthier.

B．Because they are more delicious.

C．Because people prefer organic food.

D．Because they sell better.