Download “GENE-STICKS”

NAME _______________________________
“GENETICS STIX”
Adapted from Morris Williamson of Esmond School
INTRODUCTION:
Genetics is the study of how traits are inherited. Gregor Mendel was the pioneer of
genetics in the mid-19th century and made many observations that explain the inheritance
of traits today.
OBJECTIVE:
Using popsicle sticks, the activity aims to provide a kinesthetic, visual approach to help
learn the role of genes in inheritance; understand the role of dominant and recessive
genes, and to understand the role of chance in the inheritance of traits.
MATERIALS:
6 popsicle sticks per group of 2
Length of masking tape
Colored marker or pen
1 sheet of construction paper
1 pair of scissors
Pencil – to record answers to lab questions
DIRECTIONS:
1) Take 6 popsicle sticks and do the following:
- Take 2 sticks and break them in half to make 4 short sticks
- Keep 4 popsicle sticks the full length
- Each PAIR of sticks of the same size represent one chromosome. 2N= 4.
2) Take pieces of masking tape and wrap it around each individual stick at the same
location like pictured below:
3) Take the 4 largest sticks, with the marker/pen, on one pair write a capital letter T on
the masking tape section of each one, like shown below:
On the other pair, write the lower case letter t on each one.
On one pair of smaller sticks, write a capital letter P on the masking tape of each one.
On the other pair of small sticks, write a small script p on the tape.
Answer the following questions:
a) Each pair of sticks represents a _________________________.
b) Two sticks of the same size & containing the same types of characteristics are called
________________________.
c) Each piece of tape represents the location of a _______________________, which is
a section of DNA that codes for a trait.
d) The letters you wrote on the tape represent ________________________, which are
the different possible forms of a particular gene.
Genotype: genetic makeup of an organism; its
combination of alleles
Phenotype: observable traits of an organism
Recessive: an allele that is masked in the
phenotype if dominant allele is present
T: tall plant
Homozygous: having identical alleles for a
gene
Heterozygous: having different alleles for a
gene
Dominant: a genetic feature that hides the
recessive trait in the phenotype of an organism
t: short plant
P: purple flowers
p: white flowers
Using the definitions below, make the following observations about your chromosomes:
f) Are your chromosomes homozygous or heterozygous?
g) What is the phenotype of your “T T” pair?___________________
h) What is the phenotype of you “t t” pair? ___________________
i) What is the phenotype of your “P P” pair? ___________________
j) What is the phenotype of your “p p” pair? ___________________
4) Follow the steps on meiosis using the construction paper as the “cell”. Remember
PMAT I and PMAT II. Use the scissors to cut the “cell” for cytokinesis I and II.
5) Once you have made “gametes”, write the LETTERS in their proper capitalization or
lower case form and write them in the circles below:
6) Take one of the “gametes” and “fertilize” it with one of the gametes from the other
group. Arrange the sticks in homologous pairs.
7) For your longest chromosome, write the genotype of the alleles here: ____________
What is the phenotype for this trait?: ______________________
8) For your longest chromosome, write the genotype of the alleles here: ____________
What is the phenotype for this trait?: ______________________