Almost everyone knows what a bark is. First of all, when you hear this term, there is an association with trees. However, this word has many meanings that relate to the exact sciences. It is also the name of rivers and the name of mythological characters. What “bark” is and the various meanings of the word will be discussed in this article.
We are looking for a hint in the dictionary
Considering the meaning of the word "bark", you should turn to the dictionary, which says that it:
- outer part on tree trunks;
- part of the cerebral hemispheres;
- outer hard surface of the celestial body;
- the hard shell of the planet (crust);
- sedimentary rocks of the continents that formed millions of years (continental);
- one of the types of the earth's crust (oceanic) ;
- ancient Greek goddess;
- musical instrument common in West Africa.
There are other interpretations of the studied lexeme.
As you can see from the dictionary, “bark” is a term that has quite a lot of meanings. Some of them will be described in more detail.
Part of the tree
"Bark" is a general term that combines a whole collection of wood tissues located outside the trunk or branches. It should be noted that it is also found in the stems and roots. It consists of a variety of fabrics of different origin and structure. The following plant tissues are included in the general composition:
- ritide (top layer);
- periderm (felloma, cork, felloderma, fellogen);
- pericycle (primary layer);
- secondary phloem.
In everyday life, the word under study is the name of the outer dead part of the trunk and the roots of trees and shrubs. It is divided into several types:
- scaly;
- furrowed;
- warty;
- fibrous.
The primary cortex is the outer layer of the trunk or root, which is located under the extreme integumentary tissue (epidermis in the trunk and epiblema in the roots). The secondary is under the primary and is formed from procambium cells. As the plants grow older, this inner part of the cortex is separated from new nascent layers and turns into ritide, which is subsequently discharged.
The upper shell of some trees is used in the creation of medicinal tinctures, in decorative decoration, as well as in the manufacture of corks for champagne and other wines. A special cork tree is widely used in the production of cars, planes and even spaceships.
Planet hard shell
Continuing to consider what crust means, it is necessary to talk about our planet. It has a solid outer shell. It is called the "earth's crust." This is the upper part of the lithosphere, mostly covered with water (hydrosphere).
The crust of the Earth, according to scientists, is very similar to most of those on the planets belonging to the earth group. The only exception is Mercury. The cortex of our planet is characterized by various constant movements: oscillatory and horizontal.
Most of the earth's shell consists of basalts. Scientists estimate its mass at 2.8 x 10 19 tons. Of these, about 21% are oceanic, and 79% are continental. It should be noted that the crust is only 0.473% of the total mass of our planet.
In the cerebral hemispheres
The cortex is a brain structure and a layer of gray matter that has a thickness of 1.3 to 4.5 mm. It is located on the periphery of each of the hemispheres, covering them. Its greatest thickness is in the upper parts of the postcentral and precentral convolutions, as well as the precentral lobe (lobules).
The cerebral cortex plays a crucial role in the implementation of higher mental (nervous) activity of the whole organism. It accounts for more than 80% of its total mass. In humans, on average, it is approximately 44% of the total volume of each of the hemispheres.
The cerebral cortex is divided into four types:
- Paleocortex (ancient).
- Archicortex (old).
- Neocortex (new).
- Intermediate (consists of the intermediate parts of the paleocortex and archicortex).
This membrane covers the large brain completely and forms a fairly large number of furrows, which differ in depth and length. Between them are various in size convolutions.
To date, the cerebral cortex and all other parts of it are studied quite deeply. It is known which areas of the brain are responsible for certain processes in the body. However, there are still questions that have no answers.
As can be seen from the foregoing, the cortex is a term that has a large number of meanings that affect various spheres of human life.