In some plants, the hypodermis is a layer of cells immediately below the epidermis of leaves. It is often mechanically strengthened, for example, in pine leaves, forming an extra protective layer or a water storage tissue. Deep fascia. Deep fascia (or investing fascia) is a fascia, a layer of fibrous connective tissue which can surround individual muscles, and also divide groups of muscles into compartments.
This dense fibrous connective tissue interpenetrates and surrounds the muscles, bones, nerves and blood vessels of the body. It provides connection and communication in the form of aponeuroses, ligaments, tendons, retinacula, joint capsules, and septa. The deep fasciae envelop all bone (periosteum and endosteum); cartilage (perichondrium), and blood vessels (tunica externa) and become specialized in muscles (epimysium, perimysium, and endomysium) and nerves (epineurium, perineurium, and endoneurium).
The high density of collagen fibers is what gives the deep fascia its strength and integrity. The amount of elastin fiber determines how much extensibility and resilience it will have. Examples Examples include: Fascial dynamics Deep fascia is less extensible than superficial fascia. Collagen. Elastin. Sweat gland. Sweat glands (also known as sudoriferous or sudoriparous glands, from Latin sudor, meaning "sweat"), are small tubular structures of the skin that produce sweat.
There are two main types of sweat glands that differ in their structure, function, secretory product, mechanism of excretion, anatomic distribution, and distribution across species: Eccrine sweat glands are distributed almost all over the human body, in varying densities. Its water-based secretion represents a primary form of cooling in humans.Apocrine sweat glands are mostly limited to the axilla (armpits) and perianal areas in humans. Bulbous corpuscle. The Bulbous corpuscle or Ruffini ending or Ruffini corpuscle is a slowly adapting mechanoreceptor found in the subcutaneous tissue of humans.
It is the receptor responsible for mechanoreception. It is named after Angelo Ruffini. Structure Ruffini corpuscles are enlarged dendritic endings with elongated capsules. Function This spindle-shaped receptor is sensitive to skin stretch, and contributes to the kinesthetic sense of and control of finger position and movement. In particular they are at the highest density around the fingernails where they are believed to be useful for monitoring slippage of objects along the surface of the skin, allowing modulation of grip on an object. Ruffini corpuscles respond to sustained pressure and show very little adaptation. Footnotes and references ^ Jump up to: a b "8". Lamellar corpuscle. Lamellar corpuscles, or Pacinian corpuscles, are one of the four major types of mechanoreceptor.
They are nerve endings in the skin responsible for sensitivity to vibration and pressure. They respond only to sudden disturbances and are especially sensitive to vibration. The vibrational role may be used to detect surface texture, e.g., rough vs. smooth. Lamellar corpuscles are also found in the pancreas, where they detect vibration and possibly very low frequency sounds. Lamellar corpuscles act as very rapidly adapting mechanoreceptors.
Groups of corpuscles respond to pressure changes, e.g. on grasping or releasing an object. Mast cell. The mast cell is very similar in both appearance and function to the basophil, a type of white blood cell.
However, they are not the same, as they arise from different cell lines. Origin and classification Illustration depicting mast cell activation and anaphylaxis Mast cell Mast cells were first described by Paul Ehrlich in his 1878 doctoral thesis on the basis of their unique staining characteristics and large granules. Mast cells are very similar to basophil granulocytes (a class of white blood cells) in blood. Panniculus carnosus. The panniculus carnosus is a part of the subcutaneous tissues in the study of animal anatomy.