EQ: What are genetic traits? Traits of Organisms EQ: What are genetic traits?

Vocabulary Genetics: study of heredity Heredity: genetic information is passed from one generation to the next Gene: provide the instructions on what the plant or animal will look like, how it will survive, and how it will interact with its surroundings Chromosomes: the structures in the nucleus that hold the information (DNA) from our parents Inherited Traits: characteristics that are passed on from parent to offspring. Learned behaviors: behaviors you have developed the ability to do since your birth. Trait: a feature passed from parents to offspring; sometimes referred to as a characteristic Dominant Gene: a gene for which the trait always appears (dominates) when present. Recessive Gene: a gene for which the trait usually only appears when a dominant gene is not present.

Inherited Traits & Learned Behaviors EQ: What are learned behaviors? EQ: How are inherited traits different from learned behaviors?

Getting You Thinking How would you describe yourself? You might say you have blue eyes. You might say that you like to play soccer. Many of the people in your family might also have blue eyes, but not everyone can play soccer. Your eye color came from your parents. However, your ability to play soccer was something you learned. Humans and other animals are a mix of traits. from their parents and behaviors they learned on their own.

Inherited Traits An inherited trait is a physical characteristic that is passed from parents to their offspring. These characteristics include skin, eye, and hair color. Additionally, these traits include your hair type, dimples and freckles, and a tendency to be short or tall. Have you noticed how the people in some families tend to look a lot alike? They may have the same smile, nose, or hair color. Even your ear lobes are an inherited trait (more info to come)! This is a trait that the people share. They inherited it from their parents and grandparents. Other animals have inherited traits, too, and so do plants. Gregor Mendel first discovered genetics by observing characteristics of pea plants.

Inherited Behaviors A behavior is a way of acting. Some behaviors can be inherited, or they can be learned. Inherited behaviors are called instincts. These instincts are what help many animals to survive. For example: Birds heading south in the winter Bears hibernating in the winter Birds protecting their eggs

Learned Behaviors Would you say you are better at using technology than your parents or grandparents? If so, you learned how to do this. This is not something you inherited from your parents. Behaviors are learned each and every day. Some behaviors may help us throughout our day. For example making food, riding a bike, and using manners when speaking with a neighbor. On the other hand, some behaviors do not help us. They might include playing on the Wii or eating lots of candy. Learned behaviors are things you have developed the ability to do since your birth.

Genes and Heredity EQ: What is a gene? EQ: How are traits passed on from parent to offspring?

What makes you, you? Genetic make-up

Heredity has influenced everyone’s life Heredity has influenced everyone’s life. People might tell you that your hands are just like your mother’s, you have your father’s eyes, of that your facial features identify you with one side of your family.

Other less visible characteristics (called traits) include the greater chance of having certain diseases, life expectancy, or some behavior patterns. The total number of human traits is unknown. There are more than five billion people on Earth, and each one has a different set of traits. You are really unique!

Trait Facts: Our cells are controlled by the nucleus. The nucleus also contains our genetic info on structures called CHROMOSOMES Humans have 46 chromosomes in each body cell, or 23 pairs. Each parent contributes half of each chromosome to pair to their offspring. The chromosomes themselves are made of thousands of genes. These genes are what provides information on your specific traits

Changing Genes Genes are not only found in animals, but they are found in plants. The genes control the size, shape, and color of plants. Scientists have been experimenting with ways to remove, add, and change genes. By changing the genes in certain plants, they have helped farmers grow better and faster crops. They can even make the food item taste better. Scientists have also found a way to help crops resist certain insects. Learning more about genes not only will help you understand yourself, but can help make more efficient plants and other products.

The foundation for research in the area of heredity was set in the last part of the nineteenth century by an Austrian monk named Gregor Mendel. As he worked in the monastery garden, helping to grow the vegetables, he noticed that various garden pea plants had differing traits, such as height and blossom color.

Mendel conducted experiments to change the normal self-pollinating pattern of the pea plant. He cross-pollinated a purple-flowered plant with a white-flowered plant, planted the resulting seeds, and observed the results. By repeating his experiments with other plants and then with bees and mice, he made what are considered major scientific discoveries. He developed what is often called Mendel’s first law, the law of dominance and recessiveness.

Genotype and Phenotype The two letter combination of genes is known as the GENOTYPE Example: B represents brown eyes and b represents blue eyes If a child gets a dominant and recessive gene from both parents the GENOTYPE would be Bb Since the B is a dominant trait it controls the trait; therefore, the child will have brown eyes. The specific trait is PHENOTYPE. The “PH”ysical feature

Dominance means that in a pair of genes, one tends to be superior, or dominant, and the other recessive. Long stem length, purple flowers, and rounded seeds are all dominant traits with Mendel’s pea plants.

Trait Facts: The genes themselves actually are in control for the different traits (ex. A gene may control for eye color) All genes come in pairs There are different forms of genes called ALLELES. (ex. Brown or blue eye color) Some genes are DOMINANT, or stronger and will appear more often. Others are RECESSIVE, or weaker and will appear less often Dominant genes are ALWAYS represented by a capital letter. Recessive genes are ALWAYS represented by a lower case letter

Dominant vs. Recessive Traits Most genes have two or more variations called alleles. For example, the gene for hairline shape has two alleles- widow’s peak or straight. An individual may inherit two identical or two different alleles from their parents. When two different alleles are present they interact in what is called a dominant or recessive manner If a dominant gene is present in genotype then the person will take the dominant trait.

Dominant vs. Recessive Traits Dominant and Recessive Traits in Humans Dominant Recessive Brown eyes Blue eyes Curly hair Straight hair Freckles No freckles Detached earlobes Attached earlobes Dimples when you smile No dimples when you smile Can roll tongue into the shape of a U Can’t roll tongue into the shape of a U

Determine your own traits. Color them in Picturing a Dichotomy Determine your own traits. Color them in What are our traits?

a. Gender Female: xx Male: xy

b. Eye Color Not brown eyes: e Brown eyes: E

C. Tongue Roll Not tongue roller: r Tongue Roller: R

D. Tongue Flipper Tongue Flipper: F Not tongue flipper: f

E. Ears Not attached: A Attached Ear: a

F. Hairline No widow’s peak: p Widow’s peak: P

F. Hair Not curly hair: h Curly Hair: H

Information Collected from the following resources: Gwinnett County Online Campus (SOCC) The University of Utah: Learn.Genetics http://learn.genetics.utah.edu/ National Genome Research Institute http://www.genome.gov/