1. Unit 6 Lesson 5 Punnett Squares and Pedigrees
Squared Away
How are Punnett squares used to predict patterns of heredity?
One tool for understanding the patterns of heredity is a diagram called a Punnett square.
A Punnett square is a graphic used to predict the possible genotypes of offspring in a given cross.
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2. How are Punnett squares used to predict patterns of heredity?
Unit 6 Lesson 5 Punnett Squares and Pedigrees
How are Punnett squares used to predict patterns of heredity?
Each parent has two alleles for a particular gene.
An offspring receives one allele from each parent.
Each compartment within the Punnett square shows an allele combination in a potential offspring.
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3. How can a Punnett square be used to make predictions about offspring?
Unit 6 Lesson 5 Punnett Squares and Pedigrees
How can a Punnett square be used to make predictions about offspring?
A Punnett square does not tell you what the exact results of a cross will be.
A Punnett square only helps you find the probability that a certain genotype will occur.
Probability is the mathematical chance of a specific outcome in relation to the total number of possible outcomes.
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4. How can a Punnett square be used to make predictions about offspring?
Unit 6 Lesson 5 Punnett Squares and Pedigrees
How can a Punnett square be used to make predictions about offspring?
Probability can be expressed in the form of a ratio, or an expression that compares two quantities.
Probability can also be expressed as a percentage.
A percentage states the number of times a certain outcome might happen out of 100 chances.
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5. How can a pedigree trace a trait through generations?
Unit 6 Lesson 5 Punnett Squares and Pedigrees
How can a pedigree trace a trait through generations?
A pedigree is another tool used to study patterns of inheritance.
A pedigree traces the occurrence of a trait through generations of a family.
Pedigrees can be useful in tracing sex-linked disorders, or disorders associated with an allele on a sex chromosome.
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6. How can a pedigree trace a trait through generations?
Unit 6 Lesson 5 Punnett Squares and Pedigrees
How can a pedigree trace a trait through generations?
A woman that is heterozygous for a trait is called a carrier.
She is called a carrier because she can pass the trait to her offspring.
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7. How can a pedigree trace a trait through generations?
Unit 6 Lesson 5 Punnett Squares and Pedigrees
How can a pedigree trace a trait through generations?
Pedigrees can be useful in tracing inherited disorders such as cystic fibrosis.
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8. Saving the European Mouflon
Unit 6 Lesson 5 Punnett Squares and Pedigrees
Saving the European Mouflon
Scientists use genetics to show how the European mouflon sheep can be saved from extinction.
When a population is very small, there is a risk of too much interbreeding, which can cause harmful genetic conditions to appear.
Researchers can identify and breed genetically dissimilar European mouflons in a laboratory. This lowers the risk of inherited disorders.
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