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    Genes are our basic unit of heredity. You can thank your parents for your eye color, hair color and texture, your height, your teeth, your general body build, and more. Genes are carried throughout the body on larger units called chromosomes.

    Each cell in the human body contains 23 pair of chromosomes for a total of 46, with the exception of the reproductive cells. Reproductive cells, the egg and the sperm, each contain only 23 chromosomes. This is one half of the pair. When the egg and sperm unite at conception, the zygote gains the necessary 46 for proper development.

    View a visual representation of normal and reproductive chromosomes.

    Psychology, in recent years, has focused more and more on the influence of heredity on behaviors and interests. It is important to note that just because a person inherits the ability to be great at something, does not mean the person will be.

    Let's look at an example of famous skateboarder, Tony Hawk.

    If world famous skateboarder, Tony Hawk’s children are born with the genes to skate and his children do not have a place to practice this skill, the children will not become world famous skaters. On the flip side, just because Tony Hawk’s children have a dad who is world renowned, does not mean, even with practice, his children will also be world renowned. If something is inherited, this does not mean it cannot be changed by the environment. A person may be a great skater, but only with the environmental training, will this person actually perfect the skill.


    Renowned: Famous; World known.

    Genes: A heredity unit consisting of sequence of DNA; genes are what determine our height, build, the color of our eyes and skin, and so forth.

    Chromosomes: Strand of DNA that contain the heredity information necessary for cell life.  (Zygote: A fertilized egg cell)