[ Ссылка ]
================
The salivary glands:
Sublingual gland.
Parotid gland.
Submandibular gland.
=====
The salivary glands in mammals are exocrine glands that produce saliva through a system of ducts. Humans have three paired major salivary glands (parotid, submandibular, and sublingual), as well as hundreds of minor salivary glands. Salivary glands can be classified as serous, mucous, or seromucous (mixed).
In serous secretions, the main type of protein secreted is alpha-amylase, an enzyme that breaks down starch into maltose and glucose, whereas in mucous secretions, the main protein secreted is mucin, which acts as a lubricant.
In humans, 1200 to 1500 ml of saliva are produced every day. The secretion of saliva (salivation) is mediated by parasympathetic stimulation; acetylcholine is the active neurotransmitter and binds to muscarinic receptors in the glands, leading to increased salivation.
A proposed fourth pair of salivary glands, the tubarial glands, were first identified in 2020. They are named for their location, being positioned in front of and over the torus tubarius. However, this finding from one study is yet to be confirmed.

Human teeth function to mechanically break down items of food by cutting and crushing them in preparation for swallowing and digesting. As such, they are considered part of the human digestive system.[1] Humans have four types of teeth: incisors, canines, premolars, and molars, which each have a specific function. The incisors cut the food, the canines tear the food and the molars and premolars crush the food. The roots of teeth are embedded in the maxilla (upper jaw) or the mandible (lower jaw) and are covered by gums. Teeth are made of multiple tissues of varying density and hardness.

Humans, like most other mammals, are diphyodont, meaning that they develop two sets of teeth. The first set, deciduous teeth, also called "primary teeth", "baby teeth", or "milk teeth", normally eventually contains 20 teeth. Primary teeth typically start to appear ("erupt") around six months of age and this may be distracting and/or painful for the infant. However, some babies are born with one or more visible teeth, known as neonatal teeth or "natal teeth".


The pharynx, commonly called the throat, is a passageway that extends from the base of the skull to the level of the sixth cervical vertebra. It serves both the respiratory and digestive systems by receiving air from the nasal cavity and air, food, and water from the oral cavity.
================
▶ Facebook ▶ [ Ссылка ]
▶ Instagram ▶ [ Ссылка ]
▶ TikTok ▶ [ Ссылка ]
▶ twitter ▶ [ Ссылка ]
================
Smart Doctor 👨‍⚕️
@SmartDoctor1/youtube
================
#menstrualcycle #menstruation #menstrualcycleawareness
#pregnancy #pregnant #baby
================
#anatomy #uterus
#heart #smoker #lunges #lungs #uterusproblem #fetal #love #tongue #muscles #muscle #skull #humanskull
#fetaldevelopment #fetal #fetalmovement #fetalecho #heart #baby #brain #shorts #viral#the_voice #thevoice #voice #voiceover
#SmartDoctor1
#smartdoctor
#Smart_Doctor #brain #shorts
#viral #baby#the_voice #thevoice
#voice #voiceover#oxygen #blood
#body #pregnancy #medicina #anatomy
#doctor #america
#माहवारी #月経 #임신
#妊娠 #pregnant #gravidez #information
#pronunciation #speak #speech #read

свернуть