This section through a head shows the mouth, the oral cavity (Space inside the mouth), and throat. At the back of the throat are the tonsils, which help destroy harmful bacteria that are carried into the mouth with food or in the air. The tongue is not shown, so that the other organs can be seen more clearly.
Nasal cavity
The nose is an olfactory and respiratory organ. It consists of nasal skeleton, which houses the nasal cavity. Air is carried through this space between the nostrils and throat.
Nasopharynx
This is the upper part of the throat. It is a part of the pharynx, which comprises three separate segments: the nasopharynx, oropharynx, and the hypopharynx.
Soft palate
The soft palate is the muscular part at the back of the roof of the mouth. It sits behind the hard palate, which is the bony part of the roof of the mouth. This flap stops entering the nasal cavity while swallowing.
Hard palate
The hard palate is the horizontal bony plate that makes a subsection of the palate of the mouth. It makes the anterior two-thirds of the roof of the oral cavity. This bony plate forms most of the roof of the mouth.
Tonsils
The tonsils sit at the entrance to the throat. The tonsils are part of the lymphatic system, which helps to fight infections. However, removal of the tonsils does not seem to increase susceptibility to infection. Tonsils vary widely in size and swell in response to infection.
Oropharynx
The oropharynx forms part of the pharynx, being the continuation of the oral cavity and nasopharynx superiorly, and the larynx and hypopharynx inferiorly. The oropharynx is the middle part of the throat.
Epiglottis
The epiglottis is a leaf-shaped flap of cartilage located behind the tongue, at the top of the larynx, or voice box. This flap can fold back to stop food from entering the windpipe. The epiglottis also helps with some aspects of sound production in certain languages.
Larynx (voice box)
Sounds are made when air passes through the larynx. The larynx plays an essential role in human speech. During sound production, the vocal cords close together and vibrate as air expelled from the lungs passes between them.
Windpipe (trachea)
The trachea, commonly known as the windpipe, is a tube about 4 inches long and less than an inch in diameter in most people. The trachea begins just under the larynx (voice box) and runs down behind the breastbone (sternum). The trachea then divides into two smaller tubes called bronchi: one bronchus for each lung. Sounds are made when air passes through the larynx.
Oesophagus
The oesophagus is a fibromuscular tube, approximately 25cm in length, that transports food from the pharynx to the stomach. This transports food from the throat to the stomach.
Saliva producer
Under the tongue are the sublingual glands, one of three pairs of saliva-producing (salivary) glands in the mouth. Saliva is the slimy substance that coats the mouth’s surface. It keeps the mouth moist and clean and makes chewing easier. It also contains anti-bacterial chemicals, and enzymes to break down food.
Picture Credit : Google