July 14, 2011
BEH 225
Why do people behave the way they do? What makes us tick? While our environment molds some of who we are, much more comes from heredity and hormones. Genes passed on to us from our parents make up heredity, and glands throughout the body produce hormones. As generations progress, new psychological and behavioral traits are earned and learned. This paper will explain hormones and the endocrine system, glands associated with the endocrine system, behavior genetics, and evolutionary psychology.
The endocrine system is the system of the body in which releases hormones into the bloodstream. The hormones then cause different reactions within the body, and these reactions shape part of human behavior. There are seven glands within the body, which are the pineal gland, thyroid and parathyroids, the pancreas, pituitary gland, gonads, and adrenal glands. Each gland produces diverse hormones, and each hormone has a specific effect on the body, be it mood, energy, or sexual needs (Morris and Maisto, 2002).
The pineal and pituitary glands are located in the center of the brain. The pineal gland is in the center of the brain, regulates activity levels throughout the day, and secretes melatonin, which controls the body’s sleep wake cycles. Lack of melatonin in the body causes what is known as “jet lag”, which occurs when the body’s proper sleep cycle is interrupted. The pituitary gland lies on the underside of the brain, and produces the largest number of hormones in the body, thus called the “Master Gland”. This gland influences blood pressure, contractions during childbirth, milk production, sexual behavior and interest, growth, and hydration (Morris and Maisto, 2002).
The thyroid is located below the voice box, and produces thyroxin, which regulates the body’s metabolic rate, thus controlling how thin or fat, or lazy or energetic a person is. Hyperthyroidism and hypothyroidism are diseases caused by too
References: Morris, C. G., & Maisto, A. A. (2002). Psychology: An introduction (12th ed.). Upper Saddle River, NJ: Prentice Hall. Dircx, J., M.D.(ed). (2001) . Steadman’s concise medical dictionary for health professions (4th ed.). Dayton, OH. Lippincott Williams &Wilkins.