1. Genetic Variation in Monsters
Activity
Children resemble their parents. Half of your genes come from your mother and half come from your father.
Genes come in pairs. You got one chromosome of each pair from your mother and one from your father. Along each chromosome are genes, one for each trait. This means that you have two copies of each gene, one from your mother and one from your father. Both genes of a pair deal with the same trait, but they might differ in their information about it. For instance, one gene for eye color might say green while the other one says brown. These varieties of genes are called alleles.
Procedure:
The picture shows a male and female monster, each with different genetic traits.
Your teacher will give your group a bag with a number of chromosomes.
Remove the chromosomes from the bag.
Match the chromosomes according to their numbers.
Make sure you have a Mom and Dad for each of the 3 chromosomes.
Draw a chart similar to the one below in your lab journal.
Do Task 4
Valerie posted 3.2
Errata List applied MH 6/18
Chromosome
pair number
TRAIT
Genotype
Dominate or Recessive
Phenotype 1 2 3 1 1

2. Key to Monster Genes Procedure, continued
7.12 Genetic Variation
Procedure, continued
Start with chromosome #1 and record the three traits and the genotypes for each Monster in the chart. A genotype is the genetic makeup of an organism and is based on the gene variants, or alleles, provided by each of the parents. An allele is one type of variant of a gene. In this case, a monster can have a short tail allele or a long tail allele as a variant of the tail length gene.
Determine if you have a dominant or a recessive trait. Dominant traits show up in the offspring whenever present and are represented by a capital letter in genetic charts. Recessive traits only show up if dominant traits are absent and are represented by a lowercase letter.
The phenotype of an offspring is the physical appearance, or expressed genetic traits, of an organism. Use the key below to determine the phenotype and record it.
Use the phenotype of the offspring to draw and color the baby monster in your lab journal. Label the drawing as “Phenotype.”
Write the genotype of the baby monster next to the drawing and label “Genotype.”
Replace the chromosomes in the bag.
Answer the following questions in your lab journal.
How many dominant traits does your monster have?
How many recessive traits does your monster have?
How many different alleles for tails are present?
Look at all the monsters at your table. Are any exactly alike? Explain.
Is your monster exactly like the Mom or Dad monster? Explain.
Key to Monster Genes
H = 1 horn W= 3 whiskers F= short fangs
h = 2 horns w = 2 whiskers f = long fangs
C = 3 claws T = short tail B = brown fur
c = 4 claws t = long tail b = grey fur
N = triangle nose P = purple eyes E = smooth eyebrows
n = oval nose p = blue eyes e = spikey eyebrows 2