Heredity - Maple Heights City Schools
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Transcript Heredity - Maple Heights City Schools
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....
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
Allele= Variation of a gene
◦ Example: Blue eyes or Brown Eyes
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
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.
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
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