Genetics

Age
9-12

Materials
SMART Board or LCD projector (slides with family photos), genetics chart*, students' cultural notebooks, pencils, Russian Dolls (or a set of nesting dolls)

Preparation
Introductory lesson, no prior work necessary

Presentation
1. Begin by showing the students pictures of my family. Ask them to look carefully at the pictures and make observations. Record any observations the students have on the SMART Board (switch from single screen to duel screen). Ask the students what traits they observe. Help the students generate a list of observations of similarities between family members (most have brown hair, most have brown eyes, most have round faces, etc.). 2. Tell the students that we will be learning about how certain traits are passed down from parents to their offspring. Show slide-two of mother and daughters at the same ages. "We are going to be learning how a mother with brown eyes pass down brown eyes to their daughters, or how a mother and father with dark drown hair can have a daughter with light colored hair.” 3. Read through chart on genetics (Amino Acids= letters, Gene= word, DNA= paragraph, Chromosome = chapter, Genome= book). Show students the table (on slide three). Have students copy the table into their notebooks, they should add what part of the book corresponds with each term and a short definition or picture in the third column. 4. Take out the Russian Dolls 5. Review the material on the Genetics Chart. Emphasize the movement from small to large: amino acids is the smallest, the Genome is the largest. Once five dolls are placed out, model placing Amino acid card next to the smallest doll, and so on. 6. Next, place the definition cards. (Use the following to create a material

AMINO ACIDS

GENES

DNA

CHROMOSOMES

GENOME

…is the word. These are formed by pairs of amino acids. They determine traits such as height, eye and hair color, even diseases.

…is the paragraph. One of these is made up of so many genes you have enough information to create another you!

…are the letters. A stands for adenine, T for thumine, C for cytosine, and G for guaunine. These pair up to make genes.

…is the chapter. This is DNA in a supercoil. Under a microscope, this looks like an X. The human body has twenty-three of these.

…is the book. If you took all the DNA stored in twenty-three chromosomes and strung them together you’d have…

7. Once the Labels are matched, match the definition cards. 8. Have volunteer students practice matching labels and definitions to the correct dolls.

Points Of Interest: Use the following information to create a chart. Foam core that folds into a triptych works well.

 * A chart can be made using the following material: The Letter=the Amino Acid The Gene=the Word DNA=the paragraph The Chromosome=the chapter The Genome=the book of life

The Book of Life is written with only four letters! A, G, C, T. Each letter represents an amino acid: A stands for adenine, G stands for guanine, C stands for cytosine, and T stands for thymine. These amino acids pair up in different sequences to form genes. A always pairs up with T; C always pairs up with G.

The Gene is the “word” that is formed by amino acid pairs or “letters.” In a single human cell there are more than 80,000 genes. Genes determine traits such as height, eye and hair color, even inherited diseases.

The DNA strand is the “paragraph” which is made by putting together genes or “words” in a DNA strand. Imagine taking a scissors and clipping out a section from the middle of a strip of paper. That’s what a gene is, a clipped out segment from a DNA strand. One DNA strand contains so many genes that, with them, there’s enough information to make another YOU!

A DNA strand winds up into what’s called a “supercoil.” Imagine a telephone cord. It’s already in a spiral, right? Now, keep twisting the cord and you will make a “supercoil,” where the spirals make another, bigger spiral. That’s what a chromosome is, a DNA strand in a supercoil. Under a powerful microscope, chromosomes look like an X. In the human body there are 23 chromosomes. We say that the “paragraph” of the DNA forms the 23 “chapters” or chromosomes of the book of life.

The whole “book” is called the Genome. If you took all the DNA stored in all 23 chromosomes in the human body, and strung them all together, you would have the Genome. Scientists have recently been able to identify the entire sequence of amino acid “letters” along the genome. They are able to determine 30,000 different genes! Someday they may be able to cure disease by splicing healthy genes into the DNA strand and taking out the gene that causes the illness. The Genome a huge puzzle! They’ve figured out how to make super computer do the work.