Dominant and Recessive Traits

Dominant Dominant and and

Recessive Recessive TraitsTraits

How traits are transmitted How traits are transmitted through hereditythrough heredity

Genetic Trait: Long Genetic Trait: Long Second ToeSecond Toe

Comparison of 2 Comparison of 2 Genetic TraitsGenetic Traits

Most people have a second toe that is shorter than their big toe. However, some people (about 4%) have a long second toe.

Is having a long second toe a dominant or a recessive trait?

Genetic Trait: Color Genetic Trait: Color BlindnessBlindness

Comparison of 2 Comparison of 2 Genetic TraitsGenetic Traits

Most people can see color. However, about 5,000 out of 10,000 men are color blind.

Is being color blind a dominant or a recessive trait?

Albinos have a rare genetic Albinos have a rare genetic mutation. 1 in 17,000 organisms mutation. 1 in 17,000 organisms is an albino. Is this a dominant or is an albino. Is this a dominant or

a recessive trait?a recessive trait?

AnswerAnswer

Answer: It is recessive. If an Answer: It is recessive. If an animal receives the mutated animal receives the mutated genes for albinism and for genes for albinism and for normal coloring, it is more likely normal coloring, it is more likely that the normal gene will be that the normal gene will be expressed.expressed.

QuestionQuestion

If 2 organisms reproduce and 1 of the If 2 organisms reproduce and 1 of the organisms has the dominant trait, will their organisms has the dominant trait, will their offspring have the dominant or the offspring have the dominant or the recessive trait?recessive trait?

If this albino owl (recessive trait) and this normally colored, camouflaged owl reproduced, would they have….

a.An albino babyb.A baby that has a mix of their traitsc.A normally colored baby

QuestionQuestion

If 2 organisms reproduce and 1 of the If 2 organisms reproduce and 1 of the organisms has the dominant trait, will their organisms has the dominant trait, will their offspring have the dominant or the offspring have the dominant or the recessive trait?recessive trait?

If a tall person and a short person reproduce, would their offspring be…

a.Tallb.Medium heightc.Short

MisconceptionMisconception

A misconception is an incorrect idea. One A misconception is an incorrect idea. One misconception that people used to have about misconception that people used to have about heredity was that offspring would have a ½ and heredity was that offspring would have a ½ and ½ mix of parents’ traits.½ mix of parents’ traits.

One of the people who helped correct this One of the people who helped correct this misconception was named Gregor Mendel. misconception was named Gregor Mendel.

Watch a short video clip about Mendel’s Watch a short video clip about Mendel’s discoverydiscovery

Complete a short quiz about Mendel’s discoveryComplete a short quiz about Mendel’s discovery

Mendel’s 1Mendel’s 1stst and 2 and 2ndnd GenerationsGenerations

Mendel crossed tall and short pea plants.In Mendel’s 1st generation, all of the pea plants were tall.In Mendel’s 2nd generation, ¾ of the pea plants were tall.In the next lesson, we’ll learn more about dominant and recessive traits and how they combine in offspring.

QuestionQuestion

If 2 organisms reproduce and 1 of the If 2 organisms reproduce and 1 of the organisms has the dominant trait, will their organisms has the dominant trait, will their offspring have the dominant or the offspring have the dominant or the recessive trait?recessive trait?

If this albino owl (recessive trait) and this normally colored, camouflaged owl reproduced, would they have….

a.An albino babyb.A baby that has a mix of their traitsc.A normally colored baby

Familiarize Yourself with Familiarize Yourself with a Simulationa Simulation

Gregor Mendel’s flower shop is a simulation Gregor Mendel’s flower shop is a simulation that will eventually help us use an invention that will eventually help us use an invention called a Punnett Square to breed for desired called a Punnett Square to breed for desired traits.traits.

Without knowing how to use a Punnett Without knowing how to use a Punnett Square, you will not be able to complete the Square, you will not be able to complete the entire simulation. However, practicing with entire simulation. However, practicing with the simulation will help you do it faster next the simulation will help you do it faster next week after we study the Punnett Square.week after we study the Punnett Square.