Skip to main content

The structure of human brain.

The brain is made up of two halves. Different areas of the brain have different functions. All nerve cells in the brain, about 100 billion of them, are connected to one another and transmit information. This network of the nerve cells is expanded through learning and training. Our brain controls our actions, regulates our sleep, and allows us to feel sensations like pain and joy. If it is damaged, maybe due to a stroke, one has to relearn a lot of things like speaking, walking, or eating.

How do nerve cells transmit signals?

Signals transmission through nerve cells is quite complicated. Like all the other cells, nerve cells also have a cell body with a nucleus. There are fine extended branches known as dendrites and a long 'tail' called the axon on the body of the nerve cells. Axons in the brain are smaller than 1 mm, whereas in the spinal cord they can be as long as 1 m. A chemical substance is released through an electrical impulse into the synapses present at the end of the axon. This chemical substance, known as the neurotransmitter, is transferred to the dendrite of another nerve cell and the signals are transmitted.

Why do we feel pain?

Pain is a warning signal telling us that there is some danger threatening our health. We feel pain through specific receptors, the sensors, in the skin. These can also be found in the organs and be found in the organs and the periosteum. Our body has two pain systems, a fast one and a slow one. If our hand touches a hot object, we withdraw it instinctively without even thinking. This is the fast pain system in action. However, the pain that comes later due to the burning skin or a blister, is transmitted by the slow pain system to the brain.

What is memory and why must we sleep?

It is the store of things learned and retained from our activity or experience. Our memory is a collection of knowledge, experiences, impressions, skills, habits, and many other things. It previous experiences as well as to build relationships. It has a lifelong storage capacity, and no computer of the world can match its performance. Short-term memory is the information that we are currently thinking of and it lasts for only a few seconds. Important things which we have experience and would not like to forget are transferred from short-term memory into long-term memory.
      We may not know exactly why we need to sleep, but we do know that our body needs sleep to rest and recover. One becomes irritable and cannot concentrate. After several days of inadequate sleep, one may start hallucinating. The duration of sleep needed depends on the person and the age. While most babies sleep for more than 12 hours a day, some old people need only 5-6 hours of sleep.
 

Comments

Post a Comment

Popular posts from this blog

The difference between Asteroids, comets, and Meteors.

Asteroids👈 Asteroids are small heavenly bodies, which move around the sun like the planets. Thus, they are also called planetoids. Most of them go around the sun in the asteroid belt. The asteroid belt is the space between the orbits of Mars and Jupiter. In this area, billions of small rocky heavenly objects revolve around the sun, which are known as asteroids. The belt stretches only a few kilometres across. The asteroids originated probably at the same time as the planets. Possibly they are the remains of an 'unsuccessful attempt' to build a planet. Since they are very small, the asteroids can be thrown out of their orbit by a small collision. They can then fall on Mars or on the Earth. Comets👈 Comets, like Halley's comet, which has been sighted many times in the sky, are small heavenly bodies. They are characterized by a different orbit and a bright glowing tail. Halley's comet mostly shines brightly and can be seen with the naked eyes when it is very...
Post a Comment
Read more

How are animals becoming extinct?

   Since the animals have evolved species continue to become extinct. The most well-known example of extinct species is that of the dinosaurs. Often the species cannot adjust fast enough to the changing environmental conditions, or new species arise and displace the existing ones. Today, many species are becoming extinct because of the actions of humans. Elephants, big cats, and rhinos are hunted ruthlessly, forest areas are cleared, and the grey whales are endangered. These are only a few of the species mentioned in the ' Red List'. Do you know about 'Red List'?     'Red List' comes under organization IUCN (The International Union for Conservation of Nature). The list of endangered species is known as the Red List. It lists all those plant and animal species that  are facing the threat of extinction worldwide. The list is revised every 2 years. For the year 2006, the list contained around 16,000 species of plants and animals; 530 species more than t...
Post a Comment
Read more

How can we protect nature?

   We to live close to nature; animals, plants, soil, and water are all important for our well-being. Despite this, we keep destroying the gifts of nature with pesticides, garbage, and even through tourism. We must seek ways to protect nature. For example, we should adopt use alternative eco-friendly forms of energy. Each one of us can contribute towards saving the environment by avoiding food grown with the help of pesticides and choosing a fuel-efficient means of transport. All countries must come together to save the climate of the world. The Kyoto Protocol is a major step in this direction.      The Kyoto Protocol is an international agreement aimed at fighting global warming . The countries that have signed the protocol have committed themselves to reduce the emission of greenhouse gases step by step, and thus prevent air pollution and global warming. The name of the contract come from the Japanese city of Kyoto, where this agreement was signed in 199...
Post a Comment
Read more