Download Let` review answers as a class.

Objective: Learners will be able to complete a
gallery walk activity in order to review for the
Genetics Unit of the Biology HSA exam.
Drill:
1. Take out the cards your teacher has given you.
2. Match up the vocabulary words with the definition and the picture
that best represents each word.
3. Work with your neighbor to discuss answers and then copy the
correct answers onto your “Genetics Vocabulary Chart.”
Vocabulary
Genotype
Phenotype
Homozygous
Definition
The alleles (letters) that
represent a trait. TT or tt
The external or
physical appearance of
a gene. black
Both alleles (letters) for
gene are same
Alleles (letters) for the
gene are different
Heterozygous
Picture
Think-Pair-Share: work with your neighbor and
complete questions #1-4 on your “Punnett Square
Practice Problems” worksheet.
Let’s review the answers as a class, then try some more
Punnett squares.
Let’s complete #5-7 on your “Punnett Square Practice
Problems” worksheet.
Parent 1 Genotype:
b
Bb
Brown Fur
Parent 1 Phenotype:
B
Parent 2 Genotype:
b
Bb
Bb
bb
bb
bb
Parent 2 Phenotype: White Fur
b
Genotype ratio: 2 : 2
Phenotype ratio: 2 : 2
Roger has short ears. Genevieve is heterozygous for
long ears. Use the steps below to solve the problem.
Determine the parent’s genotype and phenotype
PARENT #1:
PARENT #2:
E
1. What are the chances of a baby
with the genotype Ee?
out of
or
%
e
2. What are the chances of a baby
with short ears?
out of
or
%
e
e
Ee
ee
Ee
ee
Complete the notes on
your “Chromosomes
and Sex-Linked Traits”
worksheet.
If we take all the
chromosomes out of one cell
and match them up, we find
that we have 23 pairs.
The first 22 pairs contain the
genes that make up our
bodies (called autosomes).
The 23rd pair are called sex
chromosomes because they
determine your gender.
XX
There are two different sex
chromosomes, X and Y.
If you receive an X and a Y, you
are genetically a male.
If you receive two X’s then you
are genetically a female.
XY
X chromosomes can carry other
traits besides those related to
gender.
Sex-Linked Traits
Hemophilia
Male Pattern Baldness
Red-Green Colorblindness
Duchenne Muscular Dystrophy
Today we will look at hemophilia.
In order to have offspring
you need a female XX
and a male XY.
These crosses work just
like the ones we have
done in the past.
XX= female baby
XY= male baby
Ratio = 2:2 or 50%
Let’s cross a male with hemophilia with a carrier female.
XH
Xh
Genotype Phenotype
h
H
H
X
X X
Normal
h h
XHXh
XHXh
X x
XhXh
Carrier
hemophilia
XHY
Normal
XhY
hemophilia
XHY
Xh Y
Y
Since females have two X’s they need two alleles to get hemophilia.
Because males only have one X, they only need one allele to get
hemophilia.
Antoinette has
hemophilia but her
husband Bobby is
normal.
•Draw a Punnett
square to predict the
genotypes of their
children.
Xh
XH
Xh
XHxh
XHxh
XhY
XhY
•Determine how many
children will have
hemophilia.
Y
Mitosis starts
with one
parent cell.
Each daughter
cell also has 4
chromosomes.
Parent cell
starts with 4
chromosomes
Afterwards you
have two cells that
are identical to the
original cell.
Growth
Healing wounds
Asexual Reproduction in
Bacteria
Cancer
4 Sperm
1 Egg
Spermatogenesis
Oogenesis
46 chromosomes
Woman
produces
an egg.
23 chromosomes
The male
produces
sperm.
23 chromosomes
The sperm fertilizes the
egg to make a zygote.
Sperm and Egg only have 23 chromosomes and are created by a
process called meiosis.
Meiosis
Mitosis
Work with a partner to complete “Comparing and
Contrasting Mitosis vs. Meiosis” worksheet.
What information can we
learn from this pedigree?
Male
Female
4 Generations
Trait Inherited
What kind of trait is inherited in this family? How do you
know?
Transcription
Translation
Scribes were people that used to copy books before the
invention of the printing press.
Transcription- is when DNA is copied into RNA
DNA is our only copy of our genetic blueprint, so we
need to keep it nice and safe in the nucleus.
DNA has two
strands
DNA stays in
nucleus
DNA is larger
RNA only has one strand
RNA can go anywhere in
the cell
RNA is smaller
RNA has A,U, G, C.
DNA has A,T,G,C
We can make a copy of a portion of our DNA, called
RNA. We can then take RNA to our job site to build
our proteins. This RNA is called mRNA because it has
a message in it.
We learned earlier that DNA has a code that provides
instructions on how to build proteins. These
instructions are passed on to the mRNA
I’m a ribosome,
I read the code
in mRNA 3
letters at a time.
The code in mRNA is read 3 letters at a time. Every 3
letters is called a codon, which codes for an amino acid.
This step is called Translation.
Codon = three letters = amino acid
Third letter
GTA
CAU
CAG
GUC
We can now translate the mRNA. Each codon equals
an amino acid. We will get practice with pedigrees and
protein synthesis during our gallery walk next!
The artist captured
man’s inner struggle
with nature.
Yeah whatever. It
looks like a hot
mess to me!
You will work in groups of three to complete a gallery
walk on Genetics Review problems. You will have a set
time at each station.
Let’ review answers as a class.
Use your clickers to answer the old HSA questions.
Don’t write on the handout!!! (Then turn in your clickers
and your exit ticket paper)
Your homework is to study for your Genetics VOCAB
QUIZ!!!! Also keep working on your service learning
project!!!
Next class we will study for the evolution part of the HSA