Transcript Document
Genetics Review
Who established modern
Genetics?
(aka Father of Genetics)
•Gregor Mendel
What do geneticists call a
genetic cross made to study
a single trait?
•Monohybrid Cross
What are distinctive forms of
a gene called?
•Alleles
What is any characteristic
passed from parent to
offspring?
•A Trait
An organism that receives
different alleles from both
parents is a__________
•Hybrid
A punnett square represents
the phenotype of an
organism. T or F
•False
How do we represent the
allele for a recessive trait?
•Lowercase letter
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
Which law states that gene
pairs separate from each
other during meiosis?
•Law of segregation
If a male organism has the
genotype AABBCCDD and is
crossed with a female with
aabbccdd, what would all
of their offspring's genotypes
be?
•AaBbCcDd
If all the offspring peas in a
cross are Rr, then what were
the parent’s genotypes
•RR x rr
What is the genetic makeup
of an organism called?
•Genotype
The branch of Biology that
deals with heredity
•Genetics
Write a genotype for a
homozygous recessive trait.
•rr
Passing of traits from parent
to offspring
•Heredity
An allele that expresses itself
in a hybrid is a(n)_________.
•Dominant allele
Offspring of the P generation
•F1 generation
What is the genotypic
probability of a cross
between Bb and Bb?
•1BB:2Bb:1bb
•25%BB:50%Bb:25%bb
•¼ BB: ½ Bb: ¼ bb
Reasons Mendel studied peas
•Rapid reproduction
•Easy to cross pollinate
•Distinctive traits
•Easy to grow
Offspring of the F1 generation
•F2 generation
Write a genotype for a
heterozygous trait.
•Rr
Dominant is to Recessive as
Heterozygous is to
•Homozygous
How can we represent
Probability?
•Ratio
•Fraction
•Percentage
A person with brown eyes allele(B)
and a blue eye allele (b)has brown
eye because of which law?
•Law of Dominance
Write the genotypes for a
cross between two
heterozygous individuals for
a single trait.
•Gg X Gg
In Rabbits Black fur (B) is
dominant to Brown fur (b)
1
2
3
4
What is this device called?
Punnett Square or Monohybrid
cross
What law states that gene
pairs segregate randomly
and independently from
each other?
•Law of independent
assortment
Which Punnett Square is
worked out correctly?
D
•
d
D
d
d
d
D
DD
Dd
D
dd
Dd
d
Dd
dd
D
DD
Dd
D
DD
dd
D
Dd
dd
If you flipped a coin five
times and it came up on
heads, what is the chance
it will come up on heads
next time?
•50%
In Rabbits Black fur (B) is
dominant to Brown fur (b)
1
2
3
4
What’s the color of both parents?
Black
In Rabbits Black fur (B) is
dominant to Brown fur (b)
1
2
3
4
What is the phenotype of Box 2?
Black
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
In Rabbits Black fur (B) is
dominant to Brown fur (b)
1
2
3
4
What is the genotype of box 4?
bb
How do the offspring of 2
purebred parents look in
comparison?
•identical
Gregor Mendel used pea
plants to show what?
•How traits are
inherited
R =Round r =wrinkled
Y = yellow and y=green
X
6
7
1
3
5
4
9
2
8
What is the
genotype of
the individual
in box 2?
RrYy
R =Round r =wrinkled
Y = yellow and y=green
X
6
7
1
3
5
4
9
2
8
What is the
phenotype of
the individual
in box 1?
Round &
yellow
R =Round r =wrinkled
Y = yellow and y=green
What type of
cross is this?
X
6
7
1
3
5
4
9
2
8
Dihybrid
R =Round r =wrinkled
Y = yellow and y=green
X
6
7
1
3
5
4
9
2
8
What is the
genotype of
the individual
in box 7?
RRYy
R =Round r =wrinkled
Y = yellow and y=green
X
6
7
1
3
5
4
9
2
8
What is the
phenotype of
the individual
in box 8?
Wrinkled
& green
End of Genetics Part I