Digestive System: Phases, Teeth, Nutrients and Circulation
Phases of the Digestion Process
Phases of the process of digestion: to make the substance absorbable and useful for the body's needs:
- Separating the food: breaking it into fragments that can be ingested.
- Withdrawing from the external environment: preventing food from being contaminated by another substance.
- Locking in: keeping food in containers so that it can advance through the system.
- Moulding: increasing the surface area as much as possible.
- Mixing with liquids: facilitating and transforming the substance so that it can start to be processed.
- Passing into the body: allowing it to reach all cells (absorption).
- Expelling what we do not need: so that waste does not accumulate inside.
Teeth
Teeth are organs implanted in the bones of the upper and lower jaws through dental sockets. Each tooth has a crown (the visible part) and a root (the part implanted in the bone), and they can serve several functions:
- Incisors: sharp, chisel-shaped teeth with a single root. There are two per quadrant in both the milk and the permanent dentition.
- Canines: pointed teeth. There is one per quadrant in both the milk and permanent dentition.
- Premolars: teeth with a flat crown and tubercles. There are two per quadrant in the permanent dentition.
- Molars: teeth with a flat crown, tubercles and three roots. There are three per quadrant, only in the permanent dentition.
Hepatic Stones
Hepatic stones (gallstones) are stones formed by the precipitation of excess dissolved substances that accumulate in bile. They usually form in the gallbladder and may keep growing. When they become large enough, they can block the duct and cause significant discomfort.
Organic Substances
Majority organic substances are compounds that form the body. These are:
- Sugars: molecules intended to produce immediate energy.
- Fats: molecules intended to produce additional energy and to build structures.
- Proteins: molecules intended to build structures and regulate the functioning of the organism.
Minority organic substances: needed for everything to work properly (for example, vitamins).
Functioning of the Digestive System (3 Phases)
- Digestion of food: physical transformations (mechanical digestion) and chemical transformations (chemical digestion) of food into absorbable particles and residues.
- Absorption of useful material: incorporation of absorbed particles into the blood and lymph circulation.
- Expulsion of useless material: residues leaving the body as waste.
Flora: we call intestinal flora the set of bacteria that make up the vast majority of those in the intestines. Most bacteria are not harmful to us and some are beneficial.
Circulatory System
- Blood: blood vessels (veins and arteries), red blood cells or erythrocytes, white blood cells or leukocytes, and platelets.
- Lymphatic: lymphatic vessels.
Leukocytes: - phagocytosis (eating viruses) and synthesis of antibodies.