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. About what "bark" is, and about the various meanings of the word will be discussed in this article.
Looking for a clue in the dictionary
When considering the meaning of the word "bark", one should refer to the dictionary, which says that it is:
- outer part on tree trunks;
- part of the cerebral hemispheres;
- outer solid surface of a celestial body;
- hard shell of the planet (earth crust);
- mainland sedimentary rocks formed over 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 with quite a few meanings. Some of them will be discussedmore details.
Piece of tree
"Bark" is a general term that combines a whole set of tree tissues located on the outside of the trunk or branches. It should be noted that it is also present in stems and roots. It consists of a variety of tissues that have a different origin and structure. The general composition includes the following fabrics of plant origin:
- rhytide (top layer);
- periderm (fellema, cork, phelloderma, phellogen);
- pericycle (primary layer);
- secondary phloem.
In everyday terms, the word being studied is the name of the outer dead part of the trunk and roots of trees and shrubs. It is divided into several types:
- scaly;
- striated;
- warty;
- fibrous.
Primary bark 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 located under the primary and is formed from procambial cells. As the plant matures, this inner bark separates from the new nascent layers and becomes a rhytidome, which is subsequently shed.
The top shell of some trees is used to create medicinal tinctures, in decorative finishes, 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, aircraft and even spacecraft.
Solidshell of the planet
Continuing to consider what the crust means, it is necessary to talk about our planet. It has a hard 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 of the planets belonging to the terrestrial group. The only exception is Mercury. The crust of our planet is characterized by various constant movements: oscillatory and horizontal.
Most of the earth's shell consists of bas alts. Scientists estimate its mass at 2.8 x 1019 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.
At the hemispheres of the brain
Cortex is a structure of the brain and a layer of gray matter, having 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 gyri, as well as the precentral lobe (lobules).
The cerebral cortex plays an important role in the implementation of the higher mental (nervous) activity of the whole organism. It makes up 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 intermediate parts of the paleocortex and archicortex).
This shell covers the large brain completely and forms a fairly large number of furrows, which differ in depth and length. Between them there are convolutions of various sizes.
To date, the cerebral cortex and all its other parts have been studied quite deeply. It is known which areas of the brain are responsible for certain processes in the body. However, there are still unanswered questions.
As you can see from the above, the bark is a term that has a large number of meanings that affect various areas of human life.
