La femme dans la societe

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main food source and its chemical composition
mechanical breakdown: teeth
microbial action
chemical breakdown: time taken for foodto digest
Different species of kangaroos have different diets, although all are strict herbivores. The Eastern Grey Kangaroo ispredominantly a grazer eating a wide variety of grasses. The smaller species of kangaroos also consume hypogeal fungi. Many species are nocturnal and crepuscular.
Because of itsgrazing, kangaroos have developed specialized teeth. Its incisors are able to crop grass close to the ground, and its molars chop and grind the grass. Since the two sides ofthe lower jaw are not joined together, the lower incisors are farther apart, giving the kangaroo a wider bite. The silica in grass is abrasive, so kangaroo molars moveforward as they are ground down, and eventually fall out, replaced by new teeth that grow in the back.
Once fermentation is well underway, the partially digested food passesinto the second, tube-shaped part of the stomach, where acids and enzymes secreted by the Kangaroo complete the process of digestion
The stomach is divided into two parts:the sacciform and the tubiform. In the front part, shaped like a large sack, are millions of microscopic organisms, mainly bacteria but also fungi and protozoa. Thesemicrobes ferment the plant matter, releasing nutrients that the Kangaroo can use.Food may stay in this forestomach for up to 16 hours while fermentation takes place. TheKangaroo sometimes coughs up an undigested bit of food, and chews it some more before re-swallowing it. This is similar to a cow chewing its cud

tasmanian devil

honey possum
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