Transcript Document

Genetics Review
Part 2
If a characteristic is sexlinked, it occurs more
frequently in _______.
•Males
What is a diagram that shows
how a characteristic is
passed through a family?
•Pedigree
What are the X and Y
chromosomes called?
•Sex chromosomes
What are chromosomes
pairs1-22 called?
•Autosomes
What is an individual that
doesn’t express a given trait but
can pass it to it’s offspring?
•carrier
Red green color blindness is a sex-linked
recessive trait . In a family the father is
color blind and the mother is a carrier.
Show your work for this cross
Xb
Y
XB
XBXb
XBY
Xb
XbXb
XbY
Red green color blindness is a sex-linked
recessive trait . In a family the father is
color blind and the mother is a carrier.
What is the genotype for the
father?
r
XY
Red green color blindness is a sex-linked
recessive trait . In a family the father is
color blind and the mother is a carrier.
Out of 4 children, how many
girls would be expected to be
color blind?
1
Red green color blindness is a sex-linked
recessive trait . In a family the father is
color blind and the mother is a carrier.
Out of 4 children, how many
boys would be expected to be
color blind?
1
What gender determines the
sex of an offspring?
•Male
What is the gender of this
karyotype?
Male
What genetic condition does
this person have?
Down Syndrome
Trisomy 21
What is the gender of this
karyotype?
Male
Is this karyotype considered
“normal”?
No
How many blood types are
there?
•A
•B
•AB
•O
How many alleles do you
have for blood type?
•2
Blood types A and B are
expressed equally; they are
•codominant
If 2 people have AB blood,
what is the probability they
will have an offspring with AB
•50%
What is true about the Y
chromosome compared to
the X?
It is shorter than the X
What causes an organism to
receive too many or too few
chromosomes?
•nondisjunction
Sex-linked genes refer to
what chromosome?
•X
How many chromosomes
does a person with Down
Syndrome have?
•47
A male can produce sperm
that is either ___ or ___.
•X Y
If both parents carry the
recessive allele what is the
chance that their child will
inherit the genetic autosomal
condition?
•25%
Which Punnett Square is
worked out correctly?
•
XB
XB
XB
XBXB
XBXB
Y
XBYB
XBY
XB
XB
XB
XBXB
XBXB
Y
XBY
XBY
XB
Xb
XB
XBXB
XBXB
Y
XBY
XbY
Which Punnett Square is
worked out correctly?
X
•
X
X
X
X
X
X
XX
XX
X
XX
XX
X
XX
XX
Y
XY
XX
Y
XX
XY
Y
XY
XY
_____________is a mutation
where an organism has an
extra chromosome.
•Trisomy
Males have the sex chromosomes…
XY
Based on the pedigree shown, what is the
genotype of person II-7?
Bb
Based on the pedigree shown, how many
Daughters do the original parents have?
1
Sample pedigree - cystic fibrosis
1. What can we say
about I-1 and I-2?
2. What is the
inheritance?
3. What are the odds
that III-5 is a carrier?
4. What is the
relationship between
I-1and III-4?
5. Which individuals are
affected with cystic
fibrosis?
Which parent determines the gender of
the child?
Father
What is any characteristic
passed from parent to
offspring?
•A Trait
How do we represent the
allele for a recessive trait?
•Lowercase letter
A section of a chromosome
that codes for a trait is a
•Gene
What is the likelihood that a
particular event will occur?
•Probability
What is the genetic makeup
of an organism called?
•Genotype
The branch of Biology that
deals with heredity
•Genetics
Passing of traits from parent
to offspring
•Heredity
An allele that expresses itself
in a hybrid is a(n)_________.
•Dominant allele
All of the possible results of a
genetic cross can be shown
by using what tool?
•Punnett Square
What is the term for the
physical appearance that
an organism expresses?
•Phenotype
On a separate sheet of paper
• Draw a pedigree that represents Julie
married to Jeff, with one daughter,
Josephine. Josephine married Joseph
and had Jason and Joe. Joe married
Julia and had Shannon and fraternal twin
boys, Mark and Alex. Mark married Alison
and had Ray and Scarlet. Please label
the pedigree with the names of the
people.
• The individuals in red are affected with an
autosomal recessive disorder. Please
indicate the genotypes of each person in