An important part of the human musculoskeletal system is the skeleton, which consists of more than two hundred different bones. It enables people to move, supports internal organs. In addition, human bones are a concentration of minerals, as well as a shell that contains bone marrow
Secondary education and schools 2024, September
Today we will tell you everything about the illumination formula for open areas and indoors, as well as give the magnitude of the luminous flux under different circumstances
"My favorite book" is the perfect essay topic. What exactly is worth writing in an essay-reasoning, you will learn in this article
The article tells about what a kuren is, what meanings this word has and some of its synonyms are given
Speed reading is an incredibly useful skill that does not require special talents to master. If you have the desire, perseverance and a little time, you can easily master speed reading at home
All our understanding of the world around us is formed indirectly through the senses. The main ones are sight, hearing, smell and touch. You can close your eyes and ears, turn off your sense of smell, but tactile sensations will remain. Mechanoreceptors are responsible for them, one of which is Meissner's bodies. And although our understanding of the work of the organs of perception is quite broad, it is the most primitive tactile sensitive receptors that still remain an unsolved mystery
The human body consists of biological tissues permeated with a mass of blood vessels. They are responsible for the nutrition of cells and the removal of metabolites, supporting their vital activity. Arteries are a type of blood vessels that carry blood directly to the capillaries. All cells of the body receive solutes from them through the interstitial fluid
In the anterior mediastinum of the heart there is a vein formed by the confluence of the left and right brachiocephalic veins. It is called the superior vena cava and belongs to the systemic circulation
In this article we will reveal the interpretation of the word "nonsense". This is a masculine noun. It is used in colloquial speech, so it will not be superfluous to find out the true meaning of this word. The explanatory dictionary of Efremova will help us with this. It fixes the interpretation of this language unit
Inside the human body are the organs of digestion, circulation, hearing, etc. All of them are involved in ensuring the normal functioning of the body. However, it is believed that the key tasks are performed by the circulatory system
Sanity is a concept that cannot be defined unambiguously. It is clear that it is directly related to a he althy mind, to a reasonable approach to life, to rationality and adequacy. Whereas the lack of sanity is a serious obstacle in the path of life. Having lost it, a person can succumb to passions and break firewood. This article will discuss what sanity is. We will look at this from different points of view
In the body of plants and animals, various types of tissue, cells are isolated. Tissues can differ both in the structure of cells and in the structure of the intercellular substance, as well as in their functions. Different types of cells may differ in shape, size, the presence or absence of some organelles. Different types of cells form different types of tissues. Consider the main types of cells
Inorganic chemistry is part of general chemistry. It deals with the study of the properties and behavior of inorganic compounds - their structure and ability to react with other substances. This direction explores all substances, with the exception of those that are built from carbon chains (the latter are the subject of study of organic chemistry)
All nature consists of two types of substances - organic and inorganic. For examples of these substances, as well as how they are formed, read the article
As part of the school chemistry course, metals are studied in sufficient detail, but not every adult will answer the question of how to get them. Perhaps some will remember that they first mine the ore, but in fact this is not the only way
Mechanical tissue of plants: varieties, structural features and localization. Functions of mechanical tissues. Collenchyma, sclerenchyma, sclereids. Plant tissue types
Many chemical reactions need to be accelerated. To do this, special substances are introduced into the reaction mixture - catalysts. Consider the main types of catalyst, their importance for industrial production, human life
Various nitrogen compounds are found in the earth's crust and living organisms, are widely used in various industries, military affairs, agriculture and medicine. The chemical element with atomic number 7 leads the 15th group in the long version of the periodic table. In the form of a simple substance, nitrogen is found in the air envelope of the Earth - the atmosphere
Everyone who is a road user must comply with certain requirements. They are installed to preserve the life and he alth of people, prevent damage to vehicles and other property
What are the properties of substances. Classification of compounds. Physical and chemical properties of substances. Properties of living matter
Humanity strives for development and movement, reaching peaks and self-improvement. This is especially true among young people. You can give this movement the right direction with the help of olympiads, championships and other competitions
Ukraine is one of 14 states neighboring Russia on land. And the issue of relations between neighbors is very important, because Ukraine is part of the Russian world. Russians and Ukrainians have common holidays and a common history, and for most Ukrainians, Russian is their native language
Pushkin, as a real son of his Fatherland, was always worried about the fate of the people and the state. Without giving any recommendations in this work, Pushkin the playwright realistically shows the problems of all social strata and a particular person
Real schoolchildren will become active creators of society in the future. If they can take care of the environment, natural resources and their own he alth, they will be able to build a he althy and prosperous society
Mankind had to deal with many infectious diseases, but people called the plague the most severe and ruthless disease. Not so long ago, namely in 1981, a new disease was recorded, which was called AIDS. It was later called the plague of the 21st century for its rapid spread and destructive effect on the body
The ability to represent a number as a sum of digit terms can greatly facilitate the process of mental calculations. Acquaintance with the concept of "bit composition of numbers" occurs already in the first grade of elementary school
It's easier for the proud, the proud don't cry. Everyone knows the lines from the poem. But is it? Is it easier to live proud? Hardly. Sometimes pride blinds the eyes of its "owner". And it becomes a real disaster for him. The proud man does not see this, but the surrounding people suffer from this feeling. Let's talk about what it's like to be a proud person
Ufa - the capital of Bashkiria - the largest scientific, cultural and industrial center of the South Urals. Thanks to the diligence of Ufa residents, the city is one of the most comfortable in Russia for living. Wide avenues, green streets, a harmonious combination of old quarters and modern neighborhoods form the positive image of the metropolis
Events of the physical world are inextricably linked with changes in temperature. Every person gets acquainted with it in early childhood, when he realizes that ice is cold, and boiling water burns. At the same time, the understanding comes that the processes of temperature change do not occur instantly. Later at school, the student learns that it is connected with thermal motion
The subject "mathematics" requires consistent study. Gaps in knowledge are unacceptable here. This principle should be learned by every student already in the first grade. Therefore, if you skip several lessons in a row, you will have to master the material yourself. Otherwise, later there will be problems not only with mathematics, but also with other subjects related to it
Already in elementary school, students are faced with fractions. And then they appear in every topic. It is impossible to forget actions with these numbers. Therefore, you need to know all the information about ordinary and decimal fractions. These concepts are simple, the main thing is to understand everything in order
In everyday life, we often use this term. When there is something to think about, do not hesitate to voice it. What is food for thought? Where does it come from? Who gives it to us? Let's talk about this topic in the article
Rules and norms of behavior should be known to every child attending an educational institution. Teaching a child etiquette is a task not only for teachers, but also for parents
What is a permanent marker? What are its features? What types of markers exist and what are they for?
Graduation at school is an important event not only for children. It is significant for class teachers, teachers, and, of course, for parents. Therefore, it must be carried out in such a way that it remains in memory for a long time
All the land of our planet is divided into two categories - continents and islands. The difference between them lies in the size, as well as in the geological structure. Island formations, in turn, are also very different: some are very large, others are very tiny
How to find the perimeter of a geometric figure? To calculate the sum of the lengths of all sides, there are simple arithmetic formulas
Today, the states of South America are among the world's most significant producers of minerals and agricultural products. In addition, as in Africa, most countries here specialize in the extraction of several types of minerals. This economic orientation is the result of the mainland's colonial past
What is an inflorescence? What types of inflorescences are isolated in biology, how they are characterized. Simple and compound inflorescences, bothric and cymose. Examples of plants with these types of inflorescences. The biological significance of the formation of inflorescences for plants
Absolutely everyone would agree that the most beautiful part of any plant is the flower. It is not only glorified by poets and given by lovers - in nature it performs the function of sexual reproduction, which requires the process of pollination by insects. But if the plant has small flowers, the bees may not notice them. This problem is easily solved - an inflorescence is formed. This is a collection of small flowers, which has a certain pattern