Hunger center

Figure 3.2 Normally, when the stomach is full it sends a signal to the brain telling the body to stop eating. This message is carried by neurotransmitters (chemical messengers in the brain) to the hunger center in the hypothalamus (a part of the brain). Examples of neurotransmitters that carry this message are norepinephrine, serotonin, and dopamine. Many diet pills increase these same neurotransmitters that signal the brain that the stomach is full. These diet pills, called appetite suppressants, trick the brain into thinking the stomach is full and therefore decrease hunger.

A person loses weight when food intake is less than energy output. Many diet products contain cellulose, which has no nutritive value but provides bulk and makes you feel full. Some diet drugs depress the hunger center and must be used with caution, because they excite the nervous system and elevate blood pressure. Because muscular exercise is an important way to expend energy, an increase in daily exercise aids weight loss. Table 3.12 lists some activities and the amount of energy they require. 

It is believed that the mechanism of action of amphetamines lies in their ability to release epinephrine (adrenaline) and dopamine from presynaptic nerve endings, which stimulate the corresponding receptors in the CNS. It is also possible that they reduce neuronal uptake of amines as well as inhibit their degradation by monoaminoxidase (MAO). Characteristic of this series of compounds is the effect on the respiratory center, on the satiation center located in the hypothalamus, which leads to suppression of feelings of hunger, thus allowing analog of the examined compounds to be used as anorectics. 

Equation (9.38), if restricted to two particles, is identical in form to the radial component of the electronic Schrodinger equation for the hydrogen atom expressed in polar coordinates about the system s center of mass. In the case of the hydrogen atom, solution of the equation is facilitated by the simplicity of the two-particle system. In rotational spectroscopy of polyatomic molecules, the kinetic energy operator is considerably more complex in its construction. For purposes of discussion, we will confine ourselves to two examples that are relatively simple, presented without derivation, and then offer some generalizations therefrom. More advanced treatises on rotational spectroscopy are available to readers hungering for more. 

The International Potato Center, known worldwide by its Spanish acronym CAP, sees the potato and other Andean root and tuber crops as underexploited resources for agricultural development and hunger relief in developing countries. Founded in 1971, CIP has worked to enhance the cultivation, yield, processing, and consumption of potatoes. Its original mandate was expanded to include sweet potatoes and, more recently, other Andean roots and tubers in danger of extinction. 

One of the most dramatic forms of instrumental conditioning can be demonstrated after electrodes are implanted in the pleasure centers of the brain of an experimental animal. If a lever switch is now connected to an electrical device that stimulates this pleasure area, the animal will learn to press the lever. Indeed, it will learn to press it as continuously as possible. Animals have been known to work their paws raw pressing the lever, ignoring food and water beside them in spite of their hunger and thirst, ignoring a sexually receptive mate. Direct stimulation of pleasure centers in the brain can be very reinforcing ... 

Takver. (2004). Plea for help from Afghan refugees in Indonesia Refugees/Asylum seekers stranded in Indonesia have started a hunger strike to attract attention to their claims. Melbourne Independent Media Center 11 January. Retrieved Mmch 1, 2(X)9, from http //melboume.indymedia.org/print.php id=60155... 

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