Similar to an egg, the number of heads generally refers to the number of heads per 500g, such as 30-50 heads, which means that there are 30-50 heads per catty of sea cucumber. Because the sizes of sea cucumbers are different and the prices are different, we can roughly analyze the grams of each sea cucumber, just like saying that there are 7-8 eggs per catty, which means the same thing.
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Sea cucumber, belonging to the class Holothuria, is a kind of marine echinoderm living at the seaside up to 8000 meters. It has a history of over 600 million years. Sea cucumbers feed on algae and plankton on the seabed.
Sea cucumbers are covered with thorns and are widely distributed in the oceans of the world. There are many kinds of sea cucumbers along the coast of South China Sea in China, and about 20 kinds of sea cucumbers are edible. Sea ginseng, bird's nest and shark's fin are equally famous, and it is one of the eight treasures in the world. Sea cucumber is not only a precious food, but also a precious medicinal material.
References:
Baidu encyclopedia sea cucumber