REEBOP LAB

Reebops are a multicellular, sexually reproducing species. The body cells of a reebop contain 14 total (or 7 pairs of) chromosomes. Six of the seven pairs of chromosomes are autosomes, which contain the genetic information for both male and female reebops. The seventh pair of chromosomes is the sex chromosomes. Identical to humans, reebop sex chromosomes are identified as X and Y with the chromosomal pair XX determining the females and the chromosomal pair XY determining the males.

Purpose: To simulate the process of meiosis and fertilization and to apply the laws of genetics to the phenotypic expression of reebop characteristics.

Materials: You will supply your materials for this lab. The only stipulation is that all materials used to make your Reebop parents and 2 Reebop babies must be recyclable materials.

Procedure:

Step One – Determine Traits, Alleles, Genotypes and Phenotypes.

The table below describes the traits you will show in your Reebop family:

Trait # / Description of Trait / Dominant Allele and Phenotype / Recessive Allele and Phenotype
1 / Body Size / B – Large body / b – small body
2 / Body Color / P – purple / p - yellow
3 / Eye Size / E – large eyes / e – small eyes
4 / Horns / H – horns present / h – horns absent
5 / Arm number / A – 2 arms / a – 4 arms
6 / Warts / N – no warts / n – warts present

Data & Observations:

Data Table 1: Parent Reebops – Both parents are heterozygous, so please fill in the chart for their genotype and phenotype (yes, this is really easy)

Trait # / Mom Reebop / Dad Reebop
Genotype / Phenotype / Genotype / Phenotype
1) Body Size
2) Body Color
3) Eye Size
4) Horns
5) Arm Number
6) Warts
7) Gender (sex chromosome pair)

Data Table 2: Baby Reebops – For each of the baby Reebops, please toss two coins. Heads indicates receipt of a dominant allele, tails indicates receipt of a recessive allele. (For the sex chromosomes, heads will indicate X, tails will indicate Y). You will need to flip 7 times for each Reebop baby.

Trait # / Reebop Baby #1 / Reebop Baby #2
Genotype / Phenotype / Genotype / Phenotype
1) Body Size
2) Body Color
3) Eye Size
4) Horns
5) Arm Number
6) Warts
7) Gender (sex chromosome pair)

Step Two – Construction of Reebop Family

Use the materials your teacher provides to construct the Reebop family – both parents and both babies…be sure to reference back to your phenotypic chart.

Analysis Questions:

1. Reebop cells have a diploid number of 14. How many chromosomes are in reebop gametes?

2. Is it possible for two organisms to have different genotypes but the same phenotype? Explain.

3. Is it possible for two organisms to have different phenotypes but the same genotype? Explain.

4. Determine the overall probability or chance of parents heterozygous for all of the traits listed in the chart below of having a baby reebop with the following traits: A one-eyed female with three body segments, four legs, red antenna and back humps, brown nose, and a fat curly tail.

Reebop Traits for this question:

Trait / Dominant / Recessive
Number of Body Segments / B – 2 / b - 3
Color of Antennae / R – red / r - silver
Color of Back Humps / P – red / p - silver
Color of Nose / N - red / n - brown
Size of Tail / F – fat / f - thin
Shape of Tail / H - straight / h - curled
Number of Eyes / E - 2 / e - 1
Number of Legs / L - 4 / l - 1