Quais são o sangue e os componentes do sistema imunológico?

By Hilde Schjerven, Ph.D.. All of us have a general idea about what blood is. The heart pumps it through our own body, and we want it to live. It’s used to swear eternal friendship. We use it to save lives. If we’re sick, the physician can test our blood to learn what’s wrong. But how do the blood reflect how we’re ill, and why is it so crucial to life?

Sangue

What are the components of blood? If you lose too much blood, for example in a injury or an accident, it may be life-threatening, and you might require a transfusão de sangue. We have the ability to donate up to half a liter, which is roughly 10 percent of our total volume de sangue, however such blood donation requires overall good health, and time to resto e recuperar depois.

Roughly half of the blood volume includes different blood cells, while the other half is blood plasma, the liquid that allows your blood to flow through your entire body. Every component in the bloodstream has their own important role, which is introduced in this report. Water is crucial for life. A human can survive for days and even weeks without food, but just a couple of days without water. The reason is that water is a source that constantly recycles.

É bom saber que

Perdemos água do nosso corpo através da urina e como evaporação da nossa pele através da transpiração. Nenhum destes processos é algo que possamos controlar conscientemente, mas são processos importantes para o controlo da temperatura para além da eliminação de produtos residuais. Por outro lado, o nosso consumo de água está sob o nosso controlo. Conseguimos água a partir do que bebemos, mas também através de refeições.

Mild dehydration can cause headache, overheating, or dizziness, but isn’t life-threatening under normal conditions. In cases of extreme dehydration, you can get liquid through intravenous transfusions straight to your blood. Along with providing blood its fluidity, so that blood cells can be transported throughout the body, water is also critical as a solvent for transportation of nutrients and waste products.

Tenha em mente

Minerals, vitamins, glucose, and various forms of proteínas, as well as the water, constitute the blood plasma. Although the colour of the blood is red, the colour of the blood plasma is in fact yellow. The red color comes from the massive number of red bloods cells, as will be clarified below. The yellow color of the blood plasma comes from the many water-soluble components, like nutrients and various signaling molecules.

Factor portador

Furthermore, your blood is the carrier of different waste products, which are filtered out of the blood into the urine via the kidneys. Additionally, the blood comprises various proteins which have both structural as well as regulating or signaling functions. One kind of significant structural components are the coagulation factors that are needed for proper blood clotting. Insulina is a good example of signaling molecule. People suffering from diabetes must carefully monitor and adjust the glucose and insulin levels in their blood, to ensure a correct balance.

As células do nosso sangue estão divididas em dois tipos principais: Os glóbulos vermelhos, e os glóbulos brancos. Além disso, existem fragmentos de células especializadas, chamadas plaquetas, que são derivadas de um tipo particular de glóbulos brancos, os megacariócitos. Os glóbulos vermelhos (hemácias, também chamados eritrócitos) consomem cerca de 45 por cento do volume total de sangue.

Hemoglobina

A cor vermelha deve-se às abundantes quantidades de hemoglobina proteica, que liga e transporta oxigénio dos pulmões através de todo o nosso corpo. Os glóbulos brancos são cruciais para o nosso sistema imunitário, que pode ser amplamente dividido entre o sistema imunitário inato e o sistema imunitário adaptativo. O sistema imunitário inato reconhece padrões que estão associados a agentes patogénicos, e monta uma reacção rápida a infecções.

The adaptive immune cells recognize specific eptiopes, and may be educated to recognize epitopes associated with disease. The response of adaptive immune cells are slower, but the instruction contributes to a “memory” so that upon after experiences, we can quickly recognize and remove the threat. Immunization relies on the capability of the adaptive immune system to recognize the pathogen and produce a protective “memory” or immunization. Lastly, the platelets, also called thrombocytes, aren’t cells, but instead cell fragments. They’re critical for blood coagulation, to make sure that upon a cut or damage to a blood vessel, the bleeding will stop.