11/19/2023 0 Comments Skull and bones wiki![]() The lips are also protected by specialized sensory cells called Meissner's corpuscles.īlood, lymph and nerve supply Blood supply īlood circulates from the upper systemic loop originating at the aortic arch, and includes: the brachiocephalic artery, left common carotid artery and left subclavian artery. They line the oral, nasal, and external auditory meatus, (ear), providing lubrication and protection against pathogens. The oral cavity is lined by a stratified squamous epithelium containing about three layers of cells. The cells of the inner oral cavity are called the buccal mucosa. ![]() The protective tissues of the oral cavity are continuous with the digestive tract are called mucosa or mucous membranes. The outer surfaces of the head and neck are lined by epithelium. ![]() ![]() These include epithelial tissues ( epithelium), connective tissues, ( ligaments and bone), muscle tissue and nervous tissue. The periodontium includes all of the support membranes of the dental structures surround and support the teeth such as the gums and the attachment surfaces and membranes. Teeth are surrounded by gingiva, or gums, part of the periodontium, support tissue of oral cavity protection. The tooth is held in location by a periodontal ligament, with the assistance of cementum. The pulp is a soft tissue area containing the nerve and blood vessels to nourish and protect the tooth, located within the pulp cavity.Ī tooth sits in a specialized socket called the alveolus. The inner portions of the tooth consist of the dentin, a bonelike tissue, and the pulp. Below the neck, holding the tooth into the bone, is the root of the tooth. As the tooth tapers below the gumline, the neck is formed. The hard white exterior covering of the tooth is the enamel. The rounded upper projections of the back teeth are cusps. The white visible part of a tooth is called the crown. They have wide surfaces that help to grind food. (4) Molars, there are twelve molars, in sets of three, at the back of the mouth.(3) Premolars (or bicuspids), the four pairs of molars are located next to the cuspids.Cuspids have a pointed edge to tear food. (2) Cuspids (or canine tooth), the four cuspids are next to each incisor.They have sharp, chisel-shaped crowns that cut food. (1) Incisors, there are eight incisors located in the front of the mouth (four on the top and four on the bottom).For example, when chewing, the upper teeth work together with the lower teeth of the same shape to bite, chew, and tear food. There are various tooth shapes for different jobs. Adults have 32 permanent teeth, and children have 20 deciduous teeth. Two rows of teeth are supported by facial bones of the skull, the maxilla above and the mandible below. The deepest layer is the miotic layer, stratum basale producing daughter cells by mitosis. Stratum germinativum also called stratum basale.The epidermis is composed of stratified squamous epithelium and is divided into the following five sublayers or strata, listed in order from outer to inner: The skin is made up of three microscopic layers: epidermis, dermis, and hypodermis. These include hair, sweat glands, sebaceous glands, and sensory nerves. The head and neck is covered in skin and its appendages, termed the integumentary system. ![]() Pharyngeal plexus, pharyngeal branch of vagus nerveĭorsal rami of middle and lower cervical nerves The spinal cord passes through the foramen magnum.Įlevates and controls side to side movement of mandible The atlas joins with the occipital condyle above and the axis below. The occipital bone joins with the atlas near the foramen magnum, a large hole ( foramen) at the base of the skull. the facial bones (14 bones: 2-zygomatic, 2-maxillary, 2-palatine, 2-nasal, 2-lacrimal, vomer, 2-inferior conchae, mandible).the cranium (8 bones: frontal, 2-parietal, occipital, 2-temporal, sphenoid, ethmoid), and.The skull can be further subdivided into: The skeletal section of the head and neck forms the top part of the axial skeleton and is made up of the skull, hyoid bone, auditory ossicles, and cervical spine. The head rests on the top part of the vertebral column, with the skull joining at C1 (the first cervical vertebra known as the atlas). This article describes the anatomy of the head and neck of the human body, including the brain, bones, muscles, blood vessels, nerves, glands, nose, mouth, teeth, tongue, and throat. JSTOR ( December 2017) ( Learn how and when to remove this template message).Unsourced material may be challenged and removed.įind sources: "Head and neck anatomy" – news Please help improve this article by adding citations to reliable sources. This article needs additional citations for verification. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |