The cardiovascular system has three main parts, the heart, blood, and blood vessels. Blood is pumped into and out of your heart to keep you alive, this is called circulation. There are two systems within the circulation movement. Pulmonary circulation and systemic circulation. Pulmonary circulation is going from your heart to your lungs and then back again. Systemic circulation is going from your heart to body tissues and back again. The arteries carry the blood away from your heart, moving to the main vessels and branching out into ever smaller vessels called arterioles, and these will become capillaries. Your capillaries are also the vessels that the blood begins its trip back to your heart through the every-merging vessels, the tiniest
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Most of our hormones are secreted constantly with the amount changing as needed. Hormones work by binding with receptors on target cells, hormones can also bind to the inside and outside of the cells. When the hormones bind themselves to the outside of a cell, they can have several different effects, by changing cellular permeability or sending the target cell a message to change enzyme activity inside that cell.
Steroids are a special class of hormones, they are powerful because steroids can bind to sites inside cells. Steroids are shaped like a ringed lipid molecule and can pass easily through the target cell membrane. By being about to pass through the membrane they can interact directly with the cell’s DNA, to change the cells activity.
Understanding how the endocrine system is controlled, we must look at the concept of homeostasis. Most chemical and physical characteristics of the body will have a standard lever or a set point. “Blood pressure, blood oxygen, heart rate, and blood sugar, for example, all have “normal” ranges” (Colbert, Ankney, & Lee. 2011. Pg. ). The control systems are nervous and endocrine, work hard to keep the levels at our ideal levels. There are ways for your body to measure the variable and a place where the “ideal” level is stored, the body has a way to correct the levels that it needs
Most of our hormones are secreted constantly with the amount changing as needed. Hormones work by binding with receptors on target cells, hormones can also bind to the inside and outside of the cells. When the hormones bind themselves to the outside of a cell, they can have several different effects, by changing cellular permeability or sending the target cell a message to change enzyme activity inside that cell.
Steroids are a special class of hormones, they are powerful because steroids can bind to sites inside cells. Steroids are shaped like a ringed lipid molecule and can pass easily through the target cell membrane. By being about to pass through the membrane they can interact directly with the cell’s DNA, to change the cells activity.
Understanding how the endocrine system is controlled, we must look at the concept of homeostasis. Most chemical and physical characteristics of the body will have a standard lever or a set point. “Blood pressure, blood oxygen, heart rate, and blood sugar, for example, all have “normal” ranges” (Colbert, Ankney, & Lee. 2011. Pg. ). The control systems are nervous and endocrine, work hard to keep the levels at our ideal levels. There are ways for your body to measure the variable and a place where the “ideal” level is stored, the body has a way to correct the levels that it needs