digestion

[cgbw]

could someone briefly explain the digestion process to me?

[blue eyes]

The digestive process consists of 5 steps: Ingestion, digestion, absorption, metabolism and excretion (though I think this could be disputed, but this is what I have in my lecture notes/slides)

Ingestion = transfer of food from outside the mouth to inside it.

Digestion = consist of mechanical breakdown that results from chewing, churning and mixing with fluid + chemical reactions by which food is reduced to it's simplest form.

Absorption = the process by which nutrients pass across the cellular lining

of the GI tract into the bloodstream for transport to various tissues in the

body.

NB: the small intestine is the primary absorption site for nutrients - they are absorbed by means of passive diffusion, osmosis, active transport and pinocytosis

Metabolism = all biochemical reactions within cells of the body.

Excretion = process of discharging waste matter from the body, or elimination of undigested products.

......Hope this helps.