Transcript Agenda 06/12/06 1. Notes - Genetics 2. Practice Problems 3

Agenda
1. Notes - Genetics
2. Marshmallow Monsters
3. Vocabulary strips
Warm-Up Question
1. Use the following terms to explain
fertilization (haploid, diploid,
gamete, zygote, chromosomes)?
Vocabulary
Genotype
Phenotype
Heterozygous
Homozygous
Dominant
Recessive
Allele
Mendel
Trait
Mendelian Genetics
Why do we look
like our parents
and
grandparents?
Gregor Mendel…
He’s THE MAN
• He studied heredity,
how characteristics or
traits are passed from
parents to offspring.
• To find out about
heredity, Mendel
studied pea plants.
Pea Plant
Why are some flowers purple and
others white?
Trait
Trait
• A type of characteristic.
• Example:
Flower color, Plant height
Eye shape, Hair color
• What determines which traits you will
have and which your kids will have?
Gene
• The genetic
information on a
chromosome for a
characteristic.
• We have 2 copies
Genes
of each gene, one
from mom and
one from dad.
Mom
Dad
Gene
for hair
Allele
• Allele: Different forms of a
gene.
• Different alleles code for
different traits.
Example
Flower Color
W = Purple
w = white
Mom Dad
W
w
Dominant Allele
Mom Dad
• Dominant Allele prevents other
Dominant
genes from
showing their traits.
• These are written
with Capital
B
Letters. (like B, R,
W)
b
Example of Dominance
• Pea plants may carry
one allele from dad w
for white flowers and
one from mom W for
purple flowers.
• Because W is
dominant, the baby pea
plant will have purple
flowers.
Mom
Dad
W
w
Recessive Gene
• Recessive Gene does not show its
trait when there is
a dominant gene.
• These are written
with lowercase
letters. a, b, c
Mom Dad
Recessive
B
b
Example of Recessive Inheritance
• If a pea plant has WW
or Ww they have a
dominant gene and will
have purple flowers.
• However if the pea plant
has two recessive
genes ww, their flowers
will be white.
Mom
Dad
w
w
Genotype
• Genotype: The genes or alleles we have
for a certain trait.
Example
• WW, Ww, or ww
• Homozygous - same (WW or ww)
• Heterozygous - different (Ww)
Phenotype
• The physical trait that is shown.
• The phenotype is determined by the
genotype.
Example
• White flower, purple flower
• Brown eyes, blue eyes
Genotype and Phenotype
Purple Flower
WW or Ww
White Flower
ww
We do not know which genes we
are going to pass to our children.
Mom
Dad
Aa
Aa
AA
Aa
Aa
aa
Can you roll your tongue?
Agenda
Mendel Letter
Bikini Bottom Worksheet
Oompha Loopa Genetics
Giants Blue hair (B) is dominant to
Eagles Green hair (b).
1. Write out the homozygous dominant,
homozygous recessive, and heterozygous
genotypes.
2. What is the phenotype for a Bb individual?
Law of Segregation
• Before meiosis, the
original parent cell has
2 of every allele.
• During meiosis, the
parent cell divides to
form a gamete (sperm
or eggs) which have
only 1 of every allele.
E
H
E = brown eyes
H = black hair
e = blue eyes
e
h = red hair
h
H
e
h
H
E
e
E
E
h
e
h
H
Law of Independent Assortment
• The separation of one pair of alleles does
not influence the separation of another pair
of alleles.
Generation
• All the individuals
and offspring born
and living at the
same time.
Do you have a widow’s peak?
Are your earlobes attached?