Humans have holozoic nutrition, which means they ingest their food whole and digest it internally. It can be summarized as follows:
Food intake- Food is taken into the oral cavity during the ingesting process. The teeth aid in food grinding, salivary amylase aids in partial starch breakdown, and the tongue aids in combining the meal with saliva and swallowing it. Bolus is the new name for the food.
Digestion- Digestion is the act of breaking down complex compounds into simpler substances. It begins in the mouth, where physical and chemical digestion take place. The bolus is ingested and arrives in the stomach, where protein digestion takes place.
Bolus is now referred to as the chyme. The chyme now travels to the small intestine, where the rest of the digestion process is finished. Carbohydrates, lipids, and the rest of the proteins will be broken down by pancreatic juice, intestinal juice, and bile. The chyme is now known as the chyle, and it travels to the big intestine to absorb the water.
Absorption- The digested food is absorbed into the bloodstream via the finger-like projections on the inner surface of the small intestine.
Assimilation- The absorbed food is then utilised to generate energy by various tissues. Excess food is stored in the liver as glycogen and adipose tissue as fats.
Excretion- Undigested material moves from the small intestine to the large intestine’s rectum, where it is expelled through the anus.
Final Answer : The digestive system breaks down the food we eat into their most basic components, such as glucose (sugars), amino acids (protein building blocks), and fatty acids (that make up fats). The nutrients are carried to each cell in the body once the broken-down food is absorbed into the bloodstream from the small intestine.