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BSC 307 Cognitive Adaptation Lesson Plan Form
Title: Inheritance: Do you know what your parents gave you?
Grade Level:
9th
Objectives: Students will develop knowledge of gene inheritance and Mendel’s
Laws. The students should be able to describe and explain the laws and
components of these laws by the end of the lesson.
Illinois State Learning Standards: : 12: Understand the fundamental concepts,
principles and interconnections of the life, physical and earth/space sciences.
11: Understand the processes of scientific inquiry and technological design to
investigate questions, conduct experiments and solve problems.
Activity Description: The students will be tested on their prior knowledge of
Genetics and inheritance by filling out a crossword puzzle for their homework the
night before the Inheritance lesson. They will do what they can without the help
of the internet and will turn them in. I will then assess how much my students
know and then give the same background information to them in a powerpoint
the day the lesson starts. This background information will include information
about Gregor Mendel, his laws, and then they will do an exploration based on
these ideas. It is loosely based off of the Reebop activity and it is called Zork
Genetics. There are three different activities, one about Inheritance and the
other two are about the other two laws. Therefore, I will have hopefully gotten
to teach the other two lessons leading up to this lesson on Inheritance. This
lesson will deal with chromosomes and matching them and creating a new baby
with different genes and a new phenotype. They will then draw their new
creature. They will then have a new baby!
Rationale: I will teach this lesson because knowing about Mendelian Genetics is
essential to Biology and needs to be taught as Mendel is the father of genetics
and leads into natural selection and evolution.
Resources: http://www.nclark.net/Genetics
* Please attach any and all handouts/worksheets to this lesson plan
NAME:
PERIOD:
BACKGROUND: After looking at our family of zorks, we are now going to look at the possibility of
what the children of the zork family will look like with two traits at a time. This is known as a double
cross. When we segregate the alleles in this case we will have four different phenotypes and nine
different genotype possibilities. We will still use the terms heterozygous and homozygous. You
will use the information from the zork genetics sheet.
EXAMPLE:
Cross a heterozygous one fang, no wing zork with a Homozygous one fang, heterozygous
two winged zork.
A. What are the possible phenotypes of the offspring in this cross?
1. Look and find what the parents are in this cross. You will have four letters (alleles) for
each parent, since we are now looking at two traits at once.
Heterozygous one fang, no wing = Ffww
Homozygous one fang, hereterzygous = FFWw
2. Set up the punnett square and segregate the letters (alleles) of each parent.
Remember that each parent must donate half of the alleles (letters) to the offspring. Each
parent will donate one of each letter of what they have! We will use a process similar in
math called FOIL. It will work like this: F= First letters of the genotype, O=outer letters of
each genotype, I=inner letters of each genotype, and L=last letters of the genotype.
Ffww = Fw (first), Fw (outer), fw (inner), fw (Last).
FFWw = FW (first), Fw (outer), FW (inner), Fw (Last)
Now place them on the punnett square and cross them like we have done in a single cross.
Fw
Fw
fw
fw
FW
FFWw
FFWw
FfWw
FfWw
Fw
FFww
FFww
Ffww
Ffww
FW
FFWw
FFWw
FfWw
FfWw
Fw
FFww
FFww
Ffww
Ffww
List the phenotypes: Look in the boxes! They are: 8 one fang, two wings and 8 one fang,
no wing zorks for the possible phenotypes.
1. Tork is homozygous for being tall and for having one leg. Vorkina is short and has two
legs.
A. What must be the phenotypes and genotypes of Torky and Vorki?
2. Torky is tall and has green hair. His wife, Morkalina as you remember is short and has
yellow hair. Use Problem number 8 from zork genetics to help you.
A. What are the phenotypes and genotypes of their offspring?
3. Spork and Vorki are both tall and have three eyes. Look at problems 7 and 9 from zork
genetics to help you.
A. What will the phenotypes and genotypes of their possible offspring be?
NAME:____________________________
PERIOD:___
BACKGROUND: A long time ago, in a galaxy far, far away, a great race of beings lived on a
planet called ZORK. The inhabitants were known as Zorkonians. They are made up of 10 basic
genes (unit) that code for their appearance. Each one of these genes is made up 2 alleles (traits).
With this in mind, there are 1,024 different possible combinations for their appearance! This is
called their phenotype or their physical appearance. If we look at their genes, there are 59,049
different combinations of the alleles! This is called the genotype or genetic makeup. Remember
that we use letters for the alleles that control the genes and one letter or allele is inherited from
each parent. You will be using Zorks, who use the same genetic principles as a pea plant, to see
how genes are passed on and inherited. You will be using Punnett Squares to do this.
Here are some things to help you. You must understand these concepts and terms! I will use
traits from the table on the next page as examples.
Phenotype: The physical appearance or what the gene makes an organism look like. Examples
would be two eyes, yellow hair, and green lips from a zork.
1. Dominant: The trait that is shown the most. Example: Green hair is dominant over yellow hair.
2. Recessive: The trait that is hidden. In this example: yellow hair.
Genotype: The genetic makeup of an organism. We use letters for the genotype. Remember
that you need to look at the genotype to see what the phenotype will be.
Example: There is a Gene or unit for hair color in a zork. The alleles or traits (individual genes) for
hair color would be yellow and green. There are 2 alleles for each gene and we use letters for
each allele. The capital letters are the dominant alleles and the lower case letters are the
recessive alleles.
Gene
Hair color
Allele
1. Green color = G
2. Yellow color = g
1. Heterozygous: The term used for different alleles. There is always one dominant and one
recessive allele. Example: Gg. There is only one possibility for this!
2. Homozygous: The term used for having the same alleles. This will be either 2 dominant
alleles or 2 recessive alleles. Example: GG or gg. There are 2 possibilities for this!
Please refer back to this to help you as you work through this assignment. You will use the table
on the next page to complete the problems that follow. Everything you need is in the table! The
following are the traits of a Zork, which we will use to study genetics. You will be studying one
family. Be sure to read each problem carefully, because in each case the information is built upon
the previous problem.
Allele
T
t
G
g
E
e
F
f
H
h
L
l
W
w
N
n
R
r
B
b
Dominant/Recessive Genotype Phenotype Heterozygous Homozygous
Trait
Tall
Dominant
TT,Tt
Tall
Tt
TT
Short
Recessive
tt
Short
tt
Green
Green
Dominant
GG,Gg
Gg
GG
hair
Hair
Yellow
Yellow
Recessive
gg
gg
hair
Hair
One Eye
Dominant
EE,Ee
One Eye
Ee
EE
Three
Three
Recessive
ee
ee
Eyes
Eyes
One
Dominant
FF,Ft
One Fang
Ff
FF
Fang
Two
Two
Recessive
ff
ff
Fangs
Fangs
Two
Two
Dominant
HH,Hh
Hh
HH
Horns
Horns
One
Recessive
hh
One Horn
hh
Horn
Purple
Purple
Dominant
LL,Ll
Ll
LL
Lips
Lips
Green
Green
Recessive
ll
ll
Lips
Lips
Two
Two
Dominant
WW,Ww
Ww
WW
Wings
Wings
No
Recessive
ww
No Wings
ww
Wings
One Leg
Dominant
NN,Nn
One Leg
Nn
NN
Two
Recessive
nn
Two Legs
nn
Legs
Green
Green
Dominant
RR,Rr
Rr
RR
Skin
Skin
Yellow
Yellow
Recessive
rr
rr
Skin
Skin
Thick
Thick
Dominant
BB,Bb
Bb
BB
Eyebrow
Eyebrow
Thin
Thin
Recessive
bb
bb
Eyebrow
Eyebrow
SINGLE CROSS PROBLEMS
1. Cross a heterozygous green skinned zork with a yellow skinned zork.
A. What do the possible offspring look
Like?
2. Cross a homozygous two horned zork with a heterozygous two horned zork.
A. What are the genotypes of the possible offspring?
3. Cross a heterozygous green haired zork with a heterozygous green haired zork.
A. What are the genotypes and phenotypes of the possible offspring?
4. Cross a green lipped zork with a heterozygous purple lipped zork.
A. What are the number of phenotypes and genotypes of the offspring? Hint: Count what is
in the boxes!
5. Tork, who is homozygous for tall meets Vorkina, who is short.
A. What are the phenotypes and genotypes if they were to have offspring?
6. Tork and Vorkina have two children. One is a boy named Torky and the other is a girl named
Vorki. Many years later, Torky meets and marries a girl named Morkalina who is short.
A. What are the possibilities for the height of their offspring?
Hint: Look at 5A for information on Torky.
7. Vorki the daughter meets a zork named Spork, who is heterozygous for tall.
A. How many will be tall? How many will be short? How many will be TT?
How many will be Tt? How many will be tt?
8. Torky has green hair and Morkalina has yellow hair. They have four children and all of them
have green hair. What phenotype and genotype must Torky be?
9. Spork and Vorki both have three eyes.
A. What would their offspring look like?
10. Using problems 5-9, give the phenotypes and genotypes of Tork, Vorkina, Torky, Morkalina,
Spork and Vorki based ONLY on the traits given in the problems.
Vanderbilt Student Volunteers for Science
vanderbilt.edu/vsvs
Winter 2007 (Revised 1/17/07)
Adapted from Reebops lesson, Girls and Science Camp
Purpose
Using the ideas and concepts introduced from ZORK GENETICS and MORE ZORK GENETICS,
students will put those ideas into practice in this assignment and will give students a visual
representation to aid in their understanding of basic Mendelian genetic principles. Both of the
above assignments should be completed before doing this activity. Students will need to refer to
the ZORK GENETICS activity table for a list of the alleles which will be needed for this activity.
Background
Interestingly, zorks make good tools for the investigation of meiosis. Students will “create” baby
zorks given genotypes that they determine by selecting paper chromosomes.
Each cell in all living organisms contains hereditary information that is encoded by a molecule
called DNA (deoxyribonucleic acid). (Show students the model of DNA) DNA is an extremely
long molecule. When this long, skinny DNA molecule is all coiled up and bunched together it is
called a chromosome. (Show students the picture of a chromosome) Each chromosome is a
separate piece of DNA, so a cell with eight chromosomes has eight long pieces of DNA. A gene is
a segment of the long DNA molecule. Different genes may be different lengths. Each gene is a
code for how a certain molecule can be made. The molecules produced by the genes can
generally be sorted into two different types: ones that run the chemical reactions in your body, and
ones that will be the structural components of your body. How an organism looks and functions is a
result of the cumulative effect of all the molecules. Any organism that has “parents” has an even
number of chromosomes, because half of the chromosomes come from the “father” and the other
half from the “mother.” For example, in plants, a pollen grain is the “father’s” contribution and an
ovule is the “mother’s” contribution. These two cells combine to make a single cell, which will grow
into a seed (the offspring).
Humans have 46 chromosomes. The chromosomes sort into 23 pairs. One chromosome in each
of the 23 pairs is from the person’s father, the other from the person’s mother. Since
chromosomes come in pairs, genes do too. One gene is located on one member of chromosome
pair, the other gene is in the same location on the opposite chromosome. The gene “pair” is
technically referred to as a gene, as both members of the pair code for the same trait. A gene can
consist of a variety of different forms, but only two forms are ever present per gene (one from the
mother, the other from the father). The two different gene forms on the pair of chromosomes may
be identical or different. The different forms that comprise a gene are called alleles.
Materials (for 30 students)
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Colored pencils
15 sets of trait strips (20 strips in each set)
“How to Draw Zork Parts” (in sheet protectors)
30 Zork Worksheets
1 DNA model
1 picture of chromosome
Copy of each student’s ZORK GENETICS assignment
Colored modeling clay (optional for extension activity)
Information
Each partner should each have a set of different colored chromosomes. (It does not matter
who gets which color, as long as each person has a different color.)
Tell the students that:
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One set of strips represent the chromosomes from the mother (female) zork. The other set
represents chromosomes from the father (male) zork.
Each STRIP represents a CHROMOSOME. Each strip has a letter, – either uppercase or
lowercase. The uppercase letters represent a DOMINANT form of the trait and the
lowercase letters represent the RECESSIVE form.
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Each PAIR of letters codes for a TRAIT (or, scientifically, an ALLELE). A DOMINANT trait
will be present if the UPPERCASE letter is present. A RECESSIVE trait occurs only when
BOTH lowercase letters are chosen.
The traits are sorted so that they are matched into same sized pairs and same letters of
the alphabet. You should have 10 pairs of same size strips (chromosomes whose letters
code for traits) for both the male and female.
Students will need to have their ZORK GENETICS assignment for the table of alleles
(traits).
Experiment
Tell the students to take the longest pair of one color of chromosomes (male) and the longest
pair of the other color of chromosomes (female) and place them FACE DOWN on their desks
so that they cannot see the letter. (Since the strips I added are not colored on both sides, have
one student select males, and another females.)
WITHOUT TURNING THE CHROMOSOMES OVER, pick one chromosome of the longest size
from one color, and pick one chromosome of the longest size of the other color. Put these in
the middle as one new pair.
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Your partner will take the remaining pair for his/her zork baby.
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Continue doing this, taking one from each pair from longest to shortest. You and your
partner should end up with ten new traits; each pair is one color chromosome and one of
the other color chromosomes (strip).
Turn over the chromosomes that remain on your table. These represent a new "baby" zork!
On the DATASHEET, record the letter found on the first color of chromosomes in the Male
Gene column. Record the letter found on the second color of chromosomes in the Female
Gene column. Be sure you copy the letters exactly, uppercase or lower-case. THIS IS
IMPORTANT!
After filling out the DATA SHEET, return all chromosomes to their proper bags.
Determine the GENOTYPE by combining the 2 letters.
o Determine if the trait is dominant or recessive.
Record the PHENOTYPE for each characteristic, using the KEY and TABLE from the
ZORK GENETICS assignment. Record this on the Zork Worksheet.
Now color and add parts to the baby zork.
EXTENSION: You can get colored modeling clay from any hobby store or toy store. I
have students make 3D models of their zorks and take pictures with a digital camera to
display around the room. This may be used as an alternative for students who do feel
comfortable drawing their zorks.
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