The circulatory or cardiovascular system is responsible for moving nutrients, wastes and gases between body cells, transporting blood across the whole body and battling disease (Circulatory System). Its principal elements are the heart, numerous blood vessels, and blood.The heart forms the circulatory system's core. This 2-sided, 4-chambered pump which distributes blood to various arteries comprises of the right and left ventricles, and right and left atria. The ventricles, situated within the heart's lower half, are responsible for pumping blood to the whole body (away from our heart), whilst the atria, situated within the heart's upper half are in charge of receiving blood from different parts of the human body. The right and left ventricles pump de-oxygenated and oxygenated blood, respectively; de-oxygenated blood is pumped to lungs while oxygenated blood is pumped to the remainder of the human body (smith, 2013). These 4 chambers are connected to one another by means of valves which control blood flow and make sure its movement is unidirectional.
Blood vessels denote a sequence of elastic tubes which transport blood from and to the heart. Blood infused with oxygen exits the heart, supplying nutrients and oxygen by means of arteries throughout the body. After traversing the capillaries, the veins take wastes and deoxygenated blood back to the heart via the two vena cavae. Blood that exits the right ventricle via the pulmonary artery is oxygenated within the lungs. Carbon dioxide in the blood is disposed, and the blood goes back through the pulmonary veins to the left atrium and ventricle (smith, 2013). The process repeats in the same way.
The partly-viscous fluid, blood comprises of white (WBC) and red (RBC) blood cells, plasma, and platelets. Plasma refers to watery matter containing sugars, proteins, minerals and fats. In one cardiac cycle, ten pints of blood, on an average, travel across an adult's body. The RBCs contain hemoglobin, a substance whose function is transportation of oxygen to cells and return of carbon dioxide to the heart.
The anterior lobes of the pituitary gland release them. The GH is stimulated through the GH-releasing hormone's secretion within the hypothalamus. The GH stimulates cell reproduction and growth within body tissues and aids in amino-acid transportation to tissue cells, followed by their conversion into essential body proteins. Further, the GH aids in releasing and utilizing fatty acids out of fat or adipose tissue as energy (Binnington and Obenchain, 2013). It also assists in regulating the level of nutrients in the blood after food consumption and while fasting. Lastly, it triggers the production of a growth factor similar to insulin within the liver. This growth factor's function is inhibition of additional GH release after sufficient quantities of thyroid-stimulating hormone and GH are secreted.
A second key endocrine gland is the adrenal gland. Its medulla produces two catechol amines: norepinephrine (NE) and epinephrine (E). The former is chiefly produced by the sympathetic nervous system's adrenergi neurons whereas the latter constitutes the chief secreted amine of the medulla (80%). Both are bound to alpha- and beta- adrenergic receptors. They alter cell activity (for instance, mobilization, quicker heart rate, adipose tissue fatty acids) by means of second messengers. Estrogen, andogren (or sex steroids), aldosterone, and cortisol are generated by the adrenal gland cortex. Aldosterone helps regulate the body's potassium and sodium balance. Rigorous exercise boosts aldosterone production. Cortisol reacts to numerous stressors such as exercise, ensuring the availability of fuel (i.e., free fatty acids and glucose) and amino acids to aid the tissue repair process (Crosta, 2015).
Pancreas makes up the third main endocrine gland. Its endocrine part (also called islets of Langerhans) comprises of numerous cells which generate hormones that flow directly into our bloodstream. One beta-cell-generated hormone is insulin, whose production occurs as a reaction to blood sugar increases. Insulin is also responsible for moving glucose into tissues and muscles from the bloodstream, for consumption as energy. Additionally, insulin aids the liver in absorbing glucose, which it stores in the form of glycogen to be utilized by the body in the course of exercise or stress, when it requires extra energy (Crosta, 2015). Another pancreas-generated hormone is glucagon, which originates from alpha cells in the pancreas when the body's blood sugar lowers. It is chiefly in charge of breaking down glycogen into glucose within the liver. Subsequently, this glucose goes into the bloodstream, restoring blood glucose levels to normal.
Water: The Only Liquid the Body Needs To live a fully healthy and functional life, water is indispensible. From the point in history when primitive species moved from the oceans to land, a major factor of survival has continually been stopping dehydration. The important adaptations that enable this are present in almost all species of animals, including man. Water makes up varying percentages of the body weight of humans from 75%
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The work environment, for example, could be conducive to this type of stress, as can the relationship with other employees and with supervisors. This type of fatigue is vastly different from the mental or physical fatigue of direct work overburden, and is also more subtle than these types of fatigue. It should therefore be carefully monitored in terms of its nature and how it interacts with other types of fatigue,
"NASA refused to comment on the information about the Russian expedition to Mars, but they said that they are studying the project with great interest. An American astronaut might possibly join the Russian cosmonauts, taking into account of the fact that Russia and the U.S.A. manage to settle economic discrepancies," in terms of financial support for the program. Still, "America plans to spend money to help prepare for this
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As for supernatural acts, the primary sources of these are God and Satan. Satan or the Devil constantly urges the individual to adopt sinful ways, to behave contrary to God's directives. To combat Satan's influence, God is always available as a guide and supporter for people in moments of indecision, of spiritual weakness, and of temptation. God's guidance and strength may be sought directly through prayer and through reading