Source: image endocrine system: public domain; http://commons.wikimedia.org/wiki/File:Illu_endocrine_system_New.png
Hello, class. So the endocrine system is another system of communication that the body uses in which it sends chemicals that are secreted by different glands that travel throughout the body and cause certain kinds of reactions. These are things like human growth in the long term or they can be short-term kinds of reactions, like the use of adrenaline to excite the body and get it ready to move.
Now these are hormones that are chemicals that are being secreted by these glands. And these are chemical messengers that affect different kinds of body functions and behaviors. They're carried by the bloodstream and the lymph system all throughout the body to cause the different cells and organs to react in different ways.
And they can be triggered by different kinds of events. These are things that are in the environment. For example, when we release adrenaline when we feel scared, as well as any kind of regular growth and life events that occur normally throughout our lives, like during adolescence when we have a lot of hormones going for our bodies.
So we're going to be taking a look at some of these endocrine glands throughout the rest of our body, and the way that they can affect our minds and behavior as well. So the first gland we'll take a look at is the adrenal glands. And the adrenal glands are these endocrine glands that are located on the top of the kidneys. And they secrete hormones that are related to stress and arousal, those short-term kinds of things.
Now there are two hormones in particular that they release. And we generally refer to these hormones in common language as adrenaline, but there are actually different names that we use for them in a scientific or psychological sense. The first one is epinephrine, which is related more to fear responses to arousal. So anything we're afraid of in an environment. And norepinephrine, which is related to anger responses.
Now both of these hormones can cause the body to do different kinds of aroused or alert kind of responses. So they might increase heart rate and blood pressure. They might release more stored up energy within our cells so we can get ready to move. They can send more blood to the muscles. Again, we're talking here about the fight or flight response, which is to say we're getting ready to do something in response to our survival.
Now next we have the pancreas, which is this long gland that's located just under the stomach and the liver above the small intestine that helps in digestion. So the pancreas has a twofold use. First, it acts as an endocrine gland by releasing hormones, like insulin and other ones, which help to regulate the body's use and production of energies and sugars.
So it can help out, like with insulin, to say how much sugar should be taken in or not taken in by our cells in our bodies. But the pancreas also acts to create digestive enzymes, which work with the bile that's released from the liver to help in the digestion that occurs within our small intestines after food has been pushed outside of our stomach. So you can see, the pancreas has an important function in lots of different ways.
And finally, there are the sex glands or the endocrine glands that produce sex hormones, which regulates sexual growth and arousal and production, especially during times like puberty. And these two glands that we're talking about are the testes in men and ovaries in women. Now the testes and the ovaries help in the production of sex hormones, like androgens, which are what we call the male hormones. And an example that is testosterone. Testosterone is an androgen.
And estrogens, which we refer to as the female hormones. But it's important to note that both androgens and estrogens are present in men, as well as women. So we have both of these in our bodies. They just occur in different kinds of amounts.
Now androgens are what we commonly call steroids. So anytime they talk about performance-enhancing drugs like steroids, that's actually the sex hormones that are being used. And androgens are linked to muscle growth in men, as well as increased aggression. And it's also related to some negative sorts of things, like baldness, impotence, and heart disease. So that might make you think twice about using these steroids in different situations.
And estrogens can be used in different kinds of situations as well. For example, estrogen is used in birth control to regulate the reproductive cycles of women. So you can see, that while these are a bit different in terms of communication, like the nervous system, they can actually have these massive, far-reaching, and long-term effects on the person's body, as well as on their mind and their behaviors.
Female sex glands which secrete estrogen affecting secondary sex characteristics such as the development of breasts and affects female sexual functioning.
Males sex glands which secrete the hormone testosterone affecting secondary sex characteristics such as facial hair and also affects male sexual functioning.
A gland in both the endocrine and digestive systems which produces and secretes insulin to control blood sugar and hunger.
An excitatory hormone secreted by the adrenal glands and related to anger.
An excitatory hormone secreted by the adrenal glands and related to fear; a.k.a. adrenaline.
Endocrine glands located on top of the kidneys which secrete hormones related to stress and arousal.