What Makes us the Way We Are?

What are Genes? Genes are basically segments of DNA found in the nucleus of a cell. Genes provide us with the “ingredients” that are needed to create a living thing. Genes are made up of chains of proteins. Each protein added to the chain helps build and maintain your body like muscles, bones, digestion, heart rate etc.

If Genes Are the Ingredients for Living Things…. What is the Recipe?  Chromosomes are what contain the recipe for making a living thing.  Chromosomes are found in the nucleus of almost every cell and are made from strands of DNA.

If you were to stretch out all the DNA from one of your cells, it would be over 3 feet (1 meter) long from end to end! You can think of chromosomes as "DNA packages" that enable all this DNA to fit in the nucleus of each cell. Normally, we have 46 of these packages in each cell; we received 23 from our mother and 23 from our father.

Why do Scientists Look at Chromosomes? Scientists can diagnose or predict genetic disorders by looking at chromosomes. This kind of analysis is used in prenatal testing and in diagnosing certain disorders, such as Down syndrome, or in diagnosing a specific type of leukemia. Such diagnosis can help patients with genetic disorders receive any medical treatment they need more quickly.

Genotype vs Phenotype Phenotype is the constellation of observable traits. Eye color Hair color Shapes and Sizes Skin color etc

genotype is the genetic endowment of the individual.  It is the genetic makeup of an individual. It can be seen through the physical appearance (phenotype), of an organism.  It is also the combination of alleles located on homologous chromosomes that determines a specific characteristic or trait.

Aspects of our phenotype can be examined through heredity. We can inherit different traits depending on how many family members possess the same trait. For example: Tongue curling Cheek dimples Attached vs. free ear lobe

Cleft Chin Widow’s Peak Hitchhiker’s Thumb Left handed vs. Right handed Eye Color

Symbols used in pedigree charts Pedigree charts show a record of the family of an individual. It can be used to study the transmission of a hereditary condition. Symbols used in pedigree charts In a marriage with five children, two daughters and three sons. The second son is affected by the condition.

Genetics is concerned with explaining the behaviour of such inherited characteristics, in terms of the underlying genetic machinery which turns a single cell (the fertilised egg) into a worm, a carrot, or a human. So genetics explains how like begets like. It also explains how, over longer time scales, living things change, or evolve, to produce the dazzling diversity of life. Why is it important? Genetics allows us to understand normal events such as development, growth and ageing in terms of the underlying molecular machinery that direct these processes, and provides an understanding of why these processes go wrong in disease. Genetics also provides us with tools to produce improved crops and livestock (we’ve been doing this for thousands of years)