Anatomy Digestive System

The four main processes in the digestive system

Ingestion, digestion, absorption, and elimination

Ingestion

Taking in of food

Digestion

Breaking down of food

Absorption

Moves food into bloodstream; It does not involve actually taking those absorbed nutrients and making them a part of the body

Assimilation

Usage of absorbed molecules

Elimination

Waste removal from the body

The digestive system is made up of two groups of organs which are…?

Alimentary canal and accessory organs

Alimentary canals

esophagus and the intestines. These organs make up the continuous tube that passes from the mouth to the anus.

Accessory Organ

They provide aid to the organs in the alimentary canal by producing enzymes or performing other actions. Ex. Salivary glands and the pancreas

Digestive tract is about BLANK meters or BLANK ft long. It can take BLANK to BLANK hours for food to pass from the mouth to the anus.

Digestive tract is about 8 meters or 28 ft long. It can take 15 to 72 hours for food to pass from the mouth to the anus.

Mouth

Mechanical digestion: The teeth chomp, chew, and tear food down into smaller pieces—> Molecular structure of the food does not change

Chemical digestion: Salivary gland secrete saliva into the mouth, breaking down starches into dextrin and maltose —> Saliva is a form of chemical digestion because it changes the molecular structure of the food—> create food boluses.

Pharynx

After the food boluses are developed in the mouth, they go down this. It is a shared connection between the nasal cavities, the mouth, the air tract, and the esophagus.

Epiglottis

It is the small flap which can open and close the entrance to the trachea (passage to the lungs). When food boluses travel through the pharynx, the epiglottis folds down to protect the airway. However, while talking, the epiglottis must be open. In order to swallow, the epiglottis must be closed. Therefore, when attempting both tasks, the epiglottis might malfunction and this could result in choking.

Esophagus

After the pharynx, food bolus is transported to the stomach via this. This is a muscle walled tube that goes from the throat to the lower digestive tract.

Peristalsis

Muscular contractions that push food down towards the stomach. To demonstrate this, imagine a sphere in a rubber tube. To move the ball out, one would squeeze the tube from one end, and slowly move their hand towards the ball to move/ push the ball out. This contraction also works against gravity—> Food boluses still move to the stomach when the individual is upside down

Stomach