The Human Body: Anatomical Terms (#2)
Ganglion: a swelling on the course of a nerve. Usually corresponds to a collection of nerve cells.
Genu: means knee: Geniculum is sometimes applied to a bent part of a structure.
Gyrus: a fold or convolution of the cerebral cortex.
Hilum: a depression or notch where blood vessels enter or leave an organ.
Humor: applied to fluids of the eye.
Infundibulum: a funnel-shaped passage.
Interdigitat: an interlocking of structures by finger-like processes, as when the fingers of the two hands are interposed.
Invaginate: a process when part of a wall of a structure is pushed inwards to that the structure which invaginates the membrane becomes partly ensheathed by it.
Isthmus: a narrow part of a duct or other passage, or a narrow strip of tissue connecting two wider parts of an organ.
Joints: places where bones meet each other (articulate). Where bones are connected by fibrous tissue, the joint is known as a fibrous joint (i.e. suture of skull). Where bones are united by cartilaginous tissue, the joint is known as a cartilaginous joint (i.e. symphysis pubis). Where a space intervenes between the articulating ends of bones, the joint is called a synovial joint (i.e. most of the joints of the body). In these joints, there is an articular capsule the encloses the joint. This capsule is lined by a synovial membrane which secretes a lubricating fluid.
Labium: lip
Lamina: A thin plate of bone or cartilage or a thin layer of softer tissues. A stratum is also used to denote a layer.
Ligament: a band of fibrous connective tissue by which bones are connected to each other. Sometimes bands of connective tissue which support the viscera or the thorax or abdomen are also known as ligaments.
Lobe: a part of an organ, often separated from the rest by a fissure. A lobule is a small lobe.
Meatus: a passage or opening.
Muscle: these structures vary in shape and size, but always consist of masses of special contractile cells which are under nervous control. It is usual to describe a muscle as possessing an origin and insertion, in the sense that when the muscle contracts, the insertion moves toward the origin. It is probably more useful to regard a muscle as possessing attachments which are approximated when the whole muscle contracts. The original of a muscle is sometimes called the head and the contractile part the belly.
Nerves: the nerves of the body can be divided into twelve pairs of cranial nerves, which arise from the brain and brainstem, 31-33 pairs of spinal nerves which arise from the spinal cord in segmental series (8 cervical, 12 thoracic, 5 lumbar, 5 sacral and 1-3 coccygeal). The spinal nerves emerge from the intervertebral foramina which lie along side of adjacent vertebrae. The pass laterally into the neck or trunk. A typical spinal nerve is formed by the union of a dorsal root, which arises from the dorsal aspect of the spinal cord and a ventral root which arises from the ventral aspect of the spinal cord. The dorsal root consists of sensory (afferent) fibers and contains a swelling called the dorsal root ganglion. This ganglion contains the cells bodies of the sensory nerve fibers. The ventral root consists of motor (efferent) nerve fibers. The nerve trunk formed by the mergence of the two roots splits immediately into a dorsal ramus and a ventral ramus. The dorsal ramus supplies the deeper muscles of the back the their overlying skin. The ventral ramus supplies muscles and skin on the lateral and ventral aspects of the body. The nerve supply of the limbs is derived entirely from the ventral rami of the spinal nerves.
Sympathetic nerves: Just at the point where the 12 thoracic and first 2 lumbar spinal nerve trunks split into a dorsal and ventral ramus, two branches leave the trunk that connect to the sympathetic chain ganglia, and these are called the communicating rami. The gray communicating ramus usually comes off first and connects to the ganglion in the sympathetic chain. It carries post ganglionic neurons from the ganglion back to the spinal nerve trunk and thence to its branches. The white communicating ramus arises a little more distal than the gray one and also connects to the sympathetic chain and its ganglia. This connection carries pre ganglionic neurons from the spinal cord to the sympathetic chain where synapses may occur at that level or past the sympathetic ganglia into other sympathetic ganglia.
Neuron: The neuron or nerve cell is the functional unit of the nervous system. Each is composed of a cell body (perikaryon) where the nucleus of the cell is located, and one or more processes. One of the processes, called the axon, is different from the others, which are called dendrites. The dendrites and body are the receiving part of the neuron and the axon is the distribution part of the neuron.
Node: a swelling or protuberance. A nodule is a small node.
Notch: an indentation or depression, usually on the border of a bone.
Nucleus: literally means a kernel or nut. In anatomy, nucleus is most often used to describe an aggregation or cluster of nerve cells.
Papilla: a small nipple-shaped elevation.
Periosteum: the fibrous covering of a bone.
Plexus: a network of nerve or vessel processes.
Pouch: pockets of peritoneum in the abdomen.
Process: an appendage or projection from the main part of a bone or organ.
Punctum: a minute opening.
The following web site does a great job of relating this information: http://home.comcast.net/~wnor/terminologyanatplanes.htm
Tags: Anatomy
