Which glands produce a hormone that maintains the balance of calcium and phosphorus in the blood?

Parathyroid glands.

Explanation:

The parathyroid glands are small endocrine glands that are located behind the thyroid gland in the neck. Its primary function is to secrete a parathyroid hormone (PTH), responsible for controlling and maintaining the balance of calcium and phosphorus in the blood within certain limits. This helps to achieve proper functioning of the muscles and nerves, and also helps maintain strong bones.

answer: 20 percent

the fish culture has become a developing commercial practice in developing countries which is already prominent in developed countries of the world. the major fish protein demand is being supplemented in developing countries is   fishing to meet the needs of the growing population. therefore, in some developing nations, the percentage of animal protein from fish in the diet can be as high as 20 percent.

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