Can you complete this task: "List the human digestive glands"? If you doubt the exact answer, then our article is for you.
Gland classification
Glands are special organs that secrete biologically active substances - enzymes. They are biological catalysts that accelerate the process of chemical reactions, but are not part of its products. They are also called secrets.
There are glands of internal, external and mixed secretion. The former secrete secrets into the bloodstream. For example, the pituitary gland, which is located at the base of the brain, synthesizes growth hormone that regulates this process. And the adrenal glands secrete adrenaline. This substance helps the body cope with stressful situations, mobilizing all its forces. The pancreas is mixed. It produces hormones that enter the bloodstream and directly into the cavity of internal organs (in particular, the stomach).
Digestive glands, such as salivary and liver, are endocrine glands. In the human body, they also include lacrimal, dairy, sweat and others.
Human digestive glands
These organs secrete enzymes that break down complex organic substances into simple ones that can be absorbed by the digestive system. Passing through the tract, proteins are broken down to amino acids, complex carbohydrates - to simple ones, lipids - to fatty acids and glycerol. This process cannot be carried out due to the mechanical processing of food with the help of teeth. Only the digestive glands can do this. Consider the mechanism of their action in more detail.
Salivary glands
The first digestive glands at their location in the tract are salivary. A person has three pairs: parotid, submandibular, sublingual. When food enters the oral cavity, or even when it is seen in the oral cavity, saliva begins to be released. It is a colorless mucous-adhesive liquid. It consists of water, enzymes and mucus - mucin. Saliva has a slightly alkaline reaction. The enzyme lysozyme is able to neutralize pathogens and heal wounds of the oral mucosa. Amylase and maltase break down complex carbohydrates into simple ones. This is easy to verify. Put a piece of bread in your mouth and in a short time it will turn into a crumb that can be easily swallowed. Mucus (mucin) envelops and moisturizes pieces of food.
Chewed and partially split food through contractions of the pharynx through the esophagus enters the stomach, where it is further exposed.
Digestive glands of the stomach
In the most expanded part of the digestive tract, the glands of the mucous membrane secrete a special substance - gastric juice - into its cavity . It is also a clear liquid, but with an acidic environment. The composition of gastric juice includes mucin, amylase and maltase enzymes that break down proteins and lipids, and hydrochloric acid. The latter stimulates the motor activity of the stomach, neutralizes pathogenic bacteria, stops putrefactive processes.
Different foods are in the human stomach for a certain time. Carbohydrate - about four hours, protein and fat - from six to eight. Liquids do not stay in the stomach, except for milk, which turns here into cottage cheese.
Pancreas
This is the only digestive gland that is mixed. It is located under the stomach, which determines its name. In the duodenum, it produces digestive juice. This is the external secretion of the pancreas. Directly into the blood, it secretes hormones insulin and glucagon, which regulate carbohydrate metabolism in the human body. In this case, the organ acts as an endocrine gland.
Liver
The digestive glands also perform a secretory, protective, synthetic and metabolic function. And all this thanks to the liver. This is the largest digestive gland. In its ducts bile is constantly formed. It is a bitter greenish yellow liquid. It consists of water, bile acids and their salts, as well as enzymes. The liver secretes its secret into the duodenum, in which the final breakdown (emulsification) of fats and the disinfection of substances harmful to the body occur.
Since the breakdown of polysaccharides begins already in the oral cavity, carbohydrate food is the most easily digestible. However, everyone can confirm that after a vegetable salad a feeling of hunger sets in very quickly. Nutritionists are advised to eat protein foods. It is energetically more valuable, and the process of its splitting and digestion lasts much longer. Remember that nutrition must be balanced.
Now do you list the digestive glands? What are their functions? We think so.