Download Heredity - Maple Heights City Schools

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DNA stores all of the information that makes
each of us who we are.
Controls the traits we possess
Trait=Physical Characteristic
Examples include skin color, eye color,
height, eye sight, hair color, etc....
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Heredity= The passing of genetic material
from parent to offspring.
Gene= Basic unit of heredity; a group of DNA
Inherited traits are controlled by genes
◦ Example: eye color
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Allele= Variation of a gene
◦ Example: Blue eyes or Brown Eyes
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Reproduction that occurs when one organism
produces offspring with identical DNA as the
parent
Advantage: Quick and only requires one
organism to reproduce.
Disadvantage: All offspring are identical or
“clones” of the parent, no genetic diversity
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Reproduction that occurs between two
organisms that result in the offspring getting
DNA from both parents
Advantages: Greater genetic diversity
Disadvantages: Takes two organisms and
more energy.
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In sexual reproduction, offspring receive one
allele from each parent.
One allele is dominant to the other allele
The dominant allele is always expressed when
present in an offspring
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Example: Eye Color
Brown is dominant=B
Blue is recessive=b
If one brown allele is present the offspring will have
brown eyes
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Punnet Squares are used to predict the traits
of the offspring between two parents based
on their alleles.
Parent 1
Parent 2
B
b
BB
Bb
bB
Bb
B Brown Eyes Brown Eyes
b Brown Eyes
Blue Eyes
Parent 1
B
Parent 2
B
b
B
Parent 1
Parent 2
B
b
B
B
BB
BB
Brown Eyes
Brown Eyes
bB
BB
Brown Eyes
Brown Eyes
Parent 1
B
Parent 2
b
b
b
Parent 1
Parent 2
b
b
B
b
bB
bb
Brown Eyes
Blue Eyes
bB
bb
Brown Eyes
Blue Eyes
Parent 1
B
Parent 2
B
B
b
Parent 1
Parent 2
B
B
B
b
BB
Bb
Brown Eyes
Brown Eyes
BB
Bb
Brown Eyes
Brown Eyes