Transcript G Standard 7 - ALCOSbiologyPowerPoints

Mendel’s Laws of Probabilities
in Offspring
Standard 7
Ashley and Irum
Mendel’s Laws: A History
Gregor Mendel was born in Heinzendorf
bei Odrau, Czech Republic. He worked as a
gardener studying beekeeping and as a physics
teacher in an abbey. He was known as the
father of modern genetics. He studied about
dominant and recessive alleles in pea plants.
He wrote a paper called, “Experiments on
Plant Hybridization”. It was published in 1866.
After peas, he studied honeybees again. He
became an abbot in 1868, after which he
discontinued his scientific work on account of
his increased administrative responsibilities.
Mendel’s Laws

The Law of
Segregation of
Characteristics:

States that from a
pair of
characteristics, only
one can be
represented in a
reproductive cell.

The Law of
Independent
Assortment:

States that the
genes for two
characteristics are
inherited
independently.
Punnett Squares


This table represents three
possible genotypes, along
with indicating how likely a
particular offspring of this
mating is to have a certain
genotype.
The capital letters
represents the dominant
gene, while the lower case
letters represents the
recessive gene.
Recessive
vs. Dominant
Inheritance
The offspring of this
mating can be affected, not
affected, or carriers as
shown by the table on the
right.
Vocabulary




Phenotype-the appearance of an organism,
resulting from the interaction of the genotype
and environment.
Genotype- the genetic make-up of an organism
that is determined by a single trait, set of traits,
or an entire complex of traits.
Heterozygous-having dissimilar pairs of genes
for any given hereditary characteristic.
Homozygous-having identical pairs of genes for
any given pair of hereditary characteristics.
What’s the Difference?
 Homozygous
genes are represented as
either both capital letters (BB) or both
lower case letters (bb).
 Heterozygous genes are represented as
one capital letter and one lower case
letter (Bb).
QUIZ TIME!!!
Take out your pens
and paper!!!!!!!!
#1: Egyptian Mau cats are genetically
crossed for certain lengths of fur. A breeder
knows that short hair is dominant over long
hair. If 75% of the kittens are born with short
hair, what are the parents’ most likely
genotypes?




A: the male is a heterozygous, short-haired cat, and
the female a homozygous short-haired cat.
B: the male is a homozygous, long-haired cat, and
the female is a heterozygous, short-haired cat.
C: the male is a homozygous, short-haired cat, and
the female is a heterozygous, short-haired cat.
D: the male is a heterozygous, short-haired cat, and
the female is a heterozygous, short-haired cat.
Because the parents both
have the less dominant gene, the
majority of the kittens must show
the less dominant gene as well.
#2: Brown eye color is dominant to
blue eye color. A heterozygous brown
eyed father and a blue eyed mother
have four children. Which statement
best describes the children’s
predicted phenotypes?




A: 50% of children will have brown eyes, and 50%
will have blue.
B: 75% of the children will have brown eyes and
25% will have blue.
C: 75% of the children will have blue eyes and
25% will have brown.
D: 100% of the children will have brown eyes.
The dominance of the
father’s brown eyes is lessened
because it is heterozygous, so
the blue-eyed trait stands out
more than 25%
#3: Which genetic cross will
produce all heterozygous
offspring?
A: RR x rr
 B: rr x rr
 C: RR x RR
 D: Rr x Rr

Heterozygous x heterozygous = homozygous
Homozygous x homozygous = heterozygous
#4: What kind of letter
represents homozygotes?
A: RR
 B: Rr

(see “What’s the Difference?”)
#5: What kind of letter
represents heterozygotes?
A: RR
 B: Rr

(see “What’s the Difference?”)
#6: The offspring of a mating
can be affected, not affected, or
________ by a trait.
 A:
Re- affected
 B: Determined
 C: Defected
 D: Carried
Carried
#7: How many Laws does
Mendel have?
A: 3
 B: 6
 C: 2
 D: 1

2
#8: What was one of Mendel’s
Laws?
A: The Law of Conservation of Mass.
 B: The Law of Segregation of
Characteristics.
 C: The Law of Recessiveness.
 D: The Law of Intensity of Alleles.

The 2 Laws are the Law of
Segregation of Characteristics
and the Law of Independent
Assortment
#9: What was Mendel’s first
job?
A: Zookeeper
 B: Biologist
 C: Geneticist
 D: Gardener

Gardener
#10: What was the name of
Mendel’s paper? What year was it
published?
A: “Experiments on Plant
Hybridization” ; 1866
 B: “Experimenting with Nature” ; 1868
 C: “Experiments on Plant
Hybridization” ; 1868
 D: “Experimenting with Nature” ; 1866

He wrote a paper named
“Experiments on Plant
Hybridization” that was published
in 1866.
#11: What things did he study?
A: Pea plants and human babies
 B: Pea plants and honeybees
 C: Chickens and lima beans
 D: Garbanzo beans and lima beans

Mendel studied the genes of
Pea plants and honeybees.
#12: For what reason did he quit
his studies?
A: He grew tired of genetics
 B: He got Ebola
 C: His father died
 D: He became an abbot

Because he became an
abbot, his workload increased
and he became immersed in his
administrative responsibilities.
#13: What did Mendel study as a
gardener?
A: Weeds
 B: Butterflies
 C: Bees
 D: Honey

Bees
#14: What is a Phenotype?




A: The appearance of an organism resulting
from the interaction of the genotype and the
environment.
B: The genetic makeup of an organism that
is determined by a trait, set of traits, or an
entire complex of traits.
C: Having dissimilar pairs of genes for any
given hereditary characteristic.
D: Having identical pairs of genes for any
given pair of hereditary characteristics.
(see “Vocabulary”)
#15: What is the Law of
Independent Assortment?




A: It states that for a characteristic, two
phenotypes can be present.
B: It states that the genes for two
characteristics are inherited independently.
C: It states that genes are assorted
independently.
D: It states that out of a pair of
characteristics, only one can be
represented in a reproductive cell.
The Law of Independent
Assortment states that the genes
for two characteristics are
inherited independently.