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Name: Kaede
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Question:
why can cows digest grasses while persons don't?

Replies:
They have a complex digestive system designed for slow digestion and also have a microbe that breaks down the cellulose sugar that makes up grass. Humans posess neither the digestive system nor the enzyme to live off of grass and such.

PF

Cows don't actually digest grass, which contains cellulose. They have a ruminant stomach, which means that their stomach is compartmentalized. Some would say they have more than one stomach. But in one of the "stomachs" they have bacteria which are able to break a specific chemical bond in cellulose that breaks it down into glucose. This is an example of mutualistic symbiosis, where both organisms benefit from a relationship. The cow benefits by being able to take advantage of a food source, and the bacteria get a ready supply of food and protection. Did you know that termites can't digest wood? They also have organisms living in their guts that break down the cellulose in wood.

vanhoeck

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