Beh/225 Heredity and Hormones

Only available on StudyMode
  • Download(s) : 125
  • Published : July 24, 2011
Open Document
Text Preview

Heredity And Hormones

2 Heredity and hormones play major roles in our behavior. In this paper I will compare and

contrast the influence of heredity and hormones on human behavior. I will also include a

discussion on the endocrine system, identification of hormones and the glands responsible for

secreting them, and genetics, behavior genetics, and evolutionary psychology. The nervous system and the endocrine system work together in what is called a constant

chemical conversation. The endocrine system helps to coordinate and integrate complex

psychological reactions. The endocrine glands release chemical substances known as hormones,

which are carried by the bloodstream throughout the body. Hormone functions are similar to

neurotransmitters because they carry messages. There are two reasons why psychologists are

interested in hormones. The first is because at certain stages of development in life, hormones

organize the nervous system and body tissues. An example would be when a child reaches

puberty and hormones cause the development of breasts in females and deeper voices in males.

The second reason is because hormones activate behaviors such as aggressiveness, sexual

behavior, and the ability to concentrate. Hormones also can have a dramatic effect on moods and

the ability to learn. The glands that regulate hormones are the endocrine glands and this includes

the thyroid gland which produces the hormone thyroxin. Thyroxin regulates the body’s

metabolism and determines how energetic, or how fat or thin a person will be. If this hormone

gets out of balance, it can cause fatigue, insomnia, or the desire to sleep yet feeling constantly

tired. The pineal gland secretes the hormone melatonin which helps to regulate sleep-wake


cycles and when disturbed can cause jet-lag. The pancreas secretes two hormones insulin and

glucagon which work against each other to help keep blood-sugar at a balanced level. If there is

not enough sugar in the blood and urine, it may lead to diabetes and if there is too much sugar it

may lead to hypoglycemia. The pituitary gland produces the largest number of different

hormones. It is also known as the “master gland” and is responsible for contractions during

childbirth, a mother’s milk production, body growth and thirst. The gonads, which is the testes in

males and ovaries in females produce the hormones androgens and estrogens. These hormones

have male and female characteristics such as increased aggressiveness and nesting behaviors.

There are two adrenal glands which affects how the body reacts to stress. The hormones released

are epinephrine and norepinephrine. Epinephrine makes the heart beat faster, stops digestion, and

sends more sugar into the bloodstream. Norepinephrine raises blood pressure and is carried

through the bloodstream where it triggers the release of an adrenocorticotropic hormone

(ACTH), which prolongs the response to stress.

Genetics, according to Morris (2005), is the study of how living things pass on traits from

one generation to the next. Genes can determine eye color, hair color, and many other physical

traits. Many heredity traits are delayed until later in life such as male-pattern baldness. Behavior

genetics study topics such as perception, learning and memory, personality, and psychological

disorders from a genetic perspective. Their goal is to try and identify what genes contribute to

such things as temperament and intelligence. Their not saying that genes directly...
tracking img