Catalyst 1.What is a transgenic organism? 2.What is a GMO? 3.Why do scientists make transgenic organisms and GMOs? What is the purpose? How does it effect society?

White Board Problem The trait being studied is round seeds (dominant) and wrinkled seeds (recessive). What percentage of the offspring will be round seeded if a heterozygous round seed is crossed with a wrinkled seed?

Agenda Review – Inheritance Patterns Notes – Sex Linked Traits – Whiteboards Independent Practice Exit Ticket

Genetics The inheritance of traits passed on from parents to offspring – Vocabulary: Trait Gene Allele Genotype Phenotype Dominant Recessive Homozygous heterozygous

Patterns of Inheritance complete dominance incomplete dominance co- dominance multiple alleles sex-linked Remember that some traits, like height, are controlled by more than 1 gene

White Board Problem In pea plants purple flowers are dominant to white flowers. If two white flowered plants are cross, what percentage of their offspring will be white flowered?

White Board Problem A man has blood type A, and his wife has blood type AB. Which blood type would never be possible in their offspring? AAB B O

White Board Problem cows can be red, white or roan. If a roan cow is crossed with a red cow, what percent of the offspring will be red?

Sex-Linked Traits I can explain the inheritance pattern of Sex-Linked Traits.

Recall that humans have 23 pairs of chromosomes. Most genes are located on one of the 22 pairs of autosomes. Genes located on the X chromosome are said to be sex- linked. The X and Y chromosomes are sex chromosomes.

Can you see these numbers? If not, you may be red- green colorblind. Why is it that… 1 in 100 women are colorblind but 1 in 10 men are colorblind

X chromosomes are much larger than Y chromosomes and contain important genes. Y chromosomes are very small and only contain a maleness-determining factor. We don’t need a Y chromosome to function. XY We have 2 copies of most of our genes… Since males only have 1 copy of each gene on the X-chromosome, all X- linked alleles are expressed in males, even if they are recessive.

Some alleles are neither dominant nor recessive, and many traits are controlled by multiple alleles or multiple genes. complete dominance incomplete dominance co- dominance multiple alleles sex-linked

Traits determined by genes located on the X chromosome are said to be sex-linked traits. Some common sex-linked traits: red-green colorblindness – can’t distinguish between shades of green and red hemophilia – blood doesn’t clot properly Duchenne muscular dystrophy – progressive weakness of the muscles; life expectancy: 25 years These diseases are all caused by a recessive allele.

Genotype Notation for Sex-linked Traits XHXhXHXh XHYXHY Female genotypes always have 2 X chromosomes. each X chromosome carries an allele a heterozygous female is called a carrier because she can pass the trait on to her offspring Male genotypes always have 1 X and 1 Y chromosome. the X chromosome carries an allele the male will show whatever allele is on the X chromosome

X H = normal phenotype X h = hemophilia XhXhXhXh ? female, hemophilia What is the gender and phenotype of the individual?

X H = normal phenotype X h = hemophilia XHXhXHXh ? female, carrier (normal) What is the gender and phenotype of the individual?

X H = normal phenotype X h = hemophilia XHXHXHXH ? female, normal What is the gender and phenotype of the individual?

X H = normal phenotype X h = hemophilia XHYXHY ? male, normal What is the gender and phenotype of the individual?

X H = normal phenotype X h = hemophilia XhYXhY ? male, hemophilia What is the gender and phenotype of the individual?

X D = normal phenotype X d = Duchenne M.D. XdYXdY ? male, Duchenne What is the gender and phenotype of the individual?

X D = normal phenotype X d = Duchenne M.D. XDXdXDXd ? female, carrier (normal) What is the gender and phenotype of the individual?

X D = normal phenotype X d = Duchenne M.D. XDYXDY ? male, normal What is the gender and phenotype of the individual?

X D = normal phenotype X d = Duchenne M.D. XDXDXDXD ? female, normal What is the gender and phenotype of the individual?

X D = normal phenotype X d = Duchenne M.D. XdXdXdXd ? female, Duchenne What is the gender and phenotype of the individual?

The allele for colorblindness is recessive and sex-linked. A carrier female has a child with a normal man. What are the likely genotypes of their children? Solving a Sex-linked Trait Problem XCXC Y XCXC XcXc XCXC Y Y XCXC XCXC XcXc XCXC XCXC 1. Read the problem. Underline the known alleles. Identify the type of inheritance as sex-linked. 3. Circle and/or write down the genotypes of the parents. Each cross needs a mother (XX) and father (XY). 4. Set up and solve Punnett Square. 5. Highlight and answer what the question is asking. 2. Choose a letter to represent each allele in the problem. X C = normal vision X c = colorblind parents: X C X c x X C Y X C X C = 25% X C Y = 25% X C X c = 25% X c Y = 25%

Class Practice

White Board Problem Color-blindness is a recessive sex-linked trait carried on the X chromosome. A color-blind man marries a woman who has no alleles for the trait. If they have a child who is male, what are the chances that he will be colorblind?

Agenda Review – Inheritance Patterns Notes – Sex Linked Traits – Whiteboards Independent Practice Exit Ticket

Independent Practice

Exit Ticket

Catalyst Red Flowers (R) are dominant to white flowers (r). If a homozygous red flower is crossed with a white flower, what percent of the offspring/babies would be white?

Catalyst Cows can be red, white or roan. If a roan cow is crossed with a white cow, what percent of the offspring will be roan?

Catalyst Color-blindness is a recessive sex-linked trait carried on the X chromosome. A color-blind man marries a woman who has no alleles for the trait. If they have a child who is male, what are the chances that he will be colorblind?

Catalyst Color blindness is inherited as a sex-linked trait in humans. Use a Punnett Square to complete a cross of a color-blind male with a female with normal vision who is a carrier of the trait

Agenda Sex-Linked Practice Problems Chromosome review Genetics Kahoot Punnett Square Quiz

Patterns of Inheritance complete dominance incomplete dominance co- dominance multiple alleles sex-linked Remember that some traits, like height, are controlled by more than 1 gene

Sex-Linked Traits I can explain the inheritance pattern of Sex-Linked Traits.

Recall that humans have 23 pairs of chromosomes. Most genes are located on one of the 22 pairs of autosomes. Genes located on the X chromosome are said to be sex- linked. The X and Y chromosomes are sex chromosomes.

X chromosomes are much larger than Y chromosomes and contain important genes. Y chromosomes are very small and only contain a maleness-determining factor. We don’t need a Y chromosome to function. XY We have 2 copies of most of our genes… Since males only have 1 copy of each gene on the X-chromosome, all X- linked alleles are expressed in males, even if they are recessive.

Genotype Notation for Sex-linked Traits XHXhXHXh XHYXHY Female genotypes always have 2 X chromosomes. each X chromosome carries an allele a heterozygous female is called a carrier because she can pass the trait on to her offspring Male genotypes always have 1 X and 1 Y chromosome. the X chromosome carries an allele the male will show whatever allele is on the X chromosome

Whiteboard with a partner For homework you completed problems 1, 3, and 5 – In groups of 3, complete an assigned problem on a large whiteboard Two groups will do 2 and 4… Gallery Walk

Agenda Sex-Linked Practice Problems Chromosome review Genetics Kahoot Punnett Square Quiz

Period 3 A blue-eyed woman and a brown-eyed man have five sons and five daughters. All the children have brown eyes. What is a likely explanation for this? a.The allele for eye color is sex-linked. b.The woman is heterozygous for blue eyes. c.The allele for brown eyes is dominant over the allele for blue eyes. d.The woman is homozygous for blue eyes and the man is heterozygous for brown eyes.

A man, who has red-green colorblindness, and his wife, who is a carrier for colorblindness, have a colorblind son. What is the probability that their next son will also be colorblind?

A man has blood type AB, and his wife has blood type AB. Which blood type would never be possible in their offspring?

The inheritance of short wings in Drosophila fruit flies is an x-linked, recessive trait. Which would most likely result if a short-winged female mates with a long-winged male? a. All offspring will be short-winged. b. All females will be long-winged, and all males will be short- winged. c. All females will be short-winged, and all males will be long- winged. d. Half of the males and females will be short-winged, and half will be long-winged.

What is the probability that a woman with Type AB blood and a man with heterozygous Type A blood would have a child with Type O blood.