Reebop Gene Expression Information s1

Marshmallow Meiosis Reebop Gene Expression Information

Phenotype & Genotype Chart

Phenotype Genotype 1 antenna AA 2 antennae Aa No antennae aa 1 hump MM 2 humps Mm 3 humps mm Orange nose QQ or Qq Green nose qq Curly tail TT or Tt Straight tail tt 2 pink eyes EE or Ee 3 pink eyes ee Red legs (6 legs) LL or Ll Black legs (6 legs) ll 3 body segments (not DD or Dd including the head) 2 body segments (not dd including the head) Name ______Date ______

Activity: Marshmallow Meiosis/Reebops

Goals: 1. To demonstrate how offspring receive a random selection of traits from their parents. 2. To explain how meiosis is responsible for the tremendous variation within a species.

Background: Reebops are imaginary creatures made out of marshmallows and other common items. They tend to live in discarded soda cans. However, they are rarely seen in the wild as they are extremely fast. Once you have a male and a female in captivity, your room will soon be filled with Reebops. They are very prolific and require minimal care. Reebops live quite comfortably in a covered shoebox with small holes punched in the sides for ventilation. Reebops helps illustrate how meiosis is an important reason for the tremendous variation that exists in every species. Reebops have only seven pairs of chromosomes, each carrying the gene/allele for a trait that affects their outward appearance (phenotype). This makes them ideal subjects for studying genetics and the transfer of traits from parent to offspring. (Many professional geneticists use fruit flies.) Mom and dad Reebop are heterozygous for all seven traits.

Materials: (per team of 4) 4 large white marshmallows, 4 pieces of two pipe cleaners in two sizes and patterns (long and red for tails, short and striped for antennae), several toothpicks, paper plate, white construction or printer paper, a small white envelope, a variety of small candies: mini-marshmallows, Tic-Tacs, Good & Plenty, Twizzlers (black and red) Genetics of Reebops hand out and student activity sheet

Procedure: 1. What I Know: Write a sentence or two about what you already know about meiosis.

2. Examine the reebop parents that are on display in your classroom. The pair will serve as the parents for the baby reebops you will create. 3. Work in table groups of four students made up of two gender teams – a team of two to represent the male parent and a team of two will represent the female parent. 4. Obtain a sheet of reebop chromosome pieces and cut apart the chromosome pairs. (Each team of two students is responsible for a set of chromosomes. Blue for male and pink for female.) 5. Set out the 2 parental sets of chromosomes with same lengths together and letters facing down 6. Members of each “gender team” should take turns selecting one chromosome of each length from each parent and place them together in a “new baby” pile. 7. The baby reebop characteristics are determined by turning over the chromosomes and encoding them according to the Genotype/Phenotype Chart. 8. Write down the genotype and phenotype of your new baby reebop on the Baby Reebop Chart. 9. One student from each group should get the materials needed to make their baby Reebop. (Caution: Do not eat any of the materials.) 10.When completed, display your baby Reebops in a designated “nursery” area. 11.Study all the offspring and note their appearance. 12. What I Did: Write a summary of the procedure you used for this activity.

13.What I Observed:

a. Baby Reebop Chart:

Your Baby Reebop’s Name

Trait Phenotype Genotype Number of antennae Number of humps Nose color Tail shape Number of eyes Color of legs (4 legs) Number of body segments(not including the head)

b. Reebop Drawing (Include your Rebop’s name.) 14.What I Learned: Write a complete description of what you learned from completing this activity.

15.What I Wonder: Pose a question about what yo may still like to know about the topic of meiosis.

16.Questions: Answer the following questions I complete statements. 1. What similarities exist in the Reebop population - all of the baby Reebops you and your classmates constructed?

2. What differences exist in the Reebop population?

3. How does this activity demonstrate meiosis – the process that occurs in sex cells (sperm and egg) by which the number of chromosomes is reduced by half?

4. Gamete cells or sex cells contain a haploid number of chromosomes – that is half the number of chromosomes as the other body cells. Autosomes (other body cells) contain a full amount of chromosomes or the diploid number. Does your baby Rebop contain the haploid or the diploid number of chromosomes? Supplies and Parts:

Antennae (1, 2, or 0) Red pipe cleaners Humps (1, 2, or 3) Mini-marshmallows Noses (1) Green or orange tic tacs Tails (1) Striped pipe cleaners Legs (4) Red or black Twizzlers – cut into 1 inch pieces Body segments (2 or Regular marshmallows 3;not including the head) Eyes (2 or 3) Pink Good & Plenty Connective tissue (Use Toothpicks (whole or broken) as many as you need.)

Sources: Several teachers have published this activity. Here are two.  Soderberg, P. (1992) Marshmallow Meiosis. The Science Teacher, 59(8)28-31.  http://home.ptd.net/~jmbacb/docs/marshmallow_meiosis_teachers_manual.pdf