CP BIOLOGY Name ______________________________ Per._______

GENETICS

WORKPACKET

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HW #1: GENETICS INTRODUCTION_____1) Which of the following describes a gene?

a. blue eyes c. red hair

b. production of normal hemoglobin d. size of nose

______2) Which of the following is a physical trait?

a. how tall you are c. amylase production

b. A-type personality d. migration of butterflies

___________3) Which of the following is considered a form of a trait or an allele?(choose two answers)

a. the loci on the chromosome that codes for length of fingers

b. the nucleotide sequence at the gene that codes for length of fingers

c. the location of a gene that determines your height

d. the code for blue eyes

______ 4) Why do genes come in pairs?

a. One is carried on the maternal homolog and one on the paternal homolog.

b. There is a gene on one chromosome (ex. the #1) and another, on a different chromosome (ex. #2 ).

c. There are two genes next to each other on the same chromosome.

d. There are two sister chromatids in every cell.

______ 5) For a specific gene loci

a. the maternal allele may be the same as the paternal allele.

b. the maternal allele may not be the same as the paternal allele.

c. the maternal and paternal alleles will always code for the same trait.

d. all of the above.

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6) One of the genes for beta hemoglobin is found on chromosome 11.

The maternal and paternal #11 chromosomes are to the right. Draw a horizontal line across the upper portion of the homologs showing an approximate location of the gene. Then, draw an imaginary nucleotide sequence to the right and left of the homologs showing that the chromosomes come from an individual who carries an allele for normal hemoglobin and one for abnormal sickle cell hemoglobin.

(Hint: Use page 5 in your notes packet and only use about 10 nucleotides to represent each sequence. You can review your protein synthesis packet for specific ideas.)

______ 7) The alleles in question #6 are

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a. homozygous b. heterozygousChoose from the following two answers to define the next two statements.

a. dominant b. recessive

_______ 8) Form of a trait that is expressed when the two alleles are different.

_________ 9) Form of a trait that is expressed when the two alleles are the same (two answers).

Identify the following as a genotype or phenotype.

____________________ 10) WW, Ww, or ww.

____________________11) White fur or Black fur.

12) Why can’t there be a heterozygous recessive genotype? ________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

In guinea pigs, black fur (B) is dominant to white fur (b). The gene for black fur is on the #1 chromosome. What are the genotypes of the following animals?

______ 13) Heterozygous or hybrid

______ 14) Homozygous dominant

______ 15) Homeozygous recessive

______________ 16) The Tobiano pattern of coat spotting in horses and ponies shown below is inherited as a simple dominant gene. Which of the following genotypes will express the “Tobiano” pattern?

a. TT b. Tt c. tt

Can you identify the genotype of this “Tobiano” patterned foal?

Why or why not?

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CP Biology

HW #2: Genetics Term Sheet/Step Reminder

Allele - An alternate or variable form of a gene

Genotype – The allele combinations an organism has for a given trait

Phenotype - The expression of a pair of alleles

Homozygous - Having 2 of the same alleles for a given trait

Heterozygous - Having 2 different alleles for a given trait

Law of Dominance - A type of inheritance pattern where one allele is expressed over another – discovered

by Mendel

Dominant allele - The allele that is shown in the heterozygous form

Recessive allele - The allele that is hidden or masked in the heterozygous form

Steps to solve a simple genetics problem involving 1 trait

Step 1 – Read the problem thoroughlyStep 2 – Make a genotype/phenotype key genotype phenotype

RR RedRr Redrr white

Step 2 – Determine the parental genotypes from the information given in the problem

Ex. A plant heterozygous for red flower color is crossed with a plant producing white flowers. What % of the offspring will have white flower color?

P1 Rr X rr(heterozygous for red flower color) (white flower color)

r Step 3 – Use the parental genotypes to set up a Punnet Square

P1 R r X r r

Step 4 – Use your Punnet square to answer the question(s) in the problem.What % of the offspring will have white flower color? 50% (2 of the 4)

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r

r

rR

Rr

Rr rr

rr

CP Bio HW #3: Understanding Punnett Squares

Answer the following questions using the Punnett Square below for reference:

R=Dominant for red carnation flowers r= Recessive for white carnation flowers

1) What do the letters across the top (first row) and down the left side of a Punnett square represent?

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

2) What do the letters inside the rectangles of the Punnett square represent? For example, what do the letters “Rr” stand for?

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

__________________________________________________________________________________________

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CP Bio HW #4: Genetics Vocabulary

1) Given the following symbols to represent alleles, circle the allele pairs that are homozygous. Draw a square around the gene pairs that are heterozygous:

DD Dd nn Ww ppss Tt CC Ss Rr Yy

2) Given the following symbols and forms of traits, circle those which are genotypes and draw a rectangle around those which are phenotypes:

blond hair JJ Tt bent little finger Ss free hanging earlobe cc

3) A dominant form for a trait is that form which can be identified in an organism that is __________________ (homozygous/ heterozygous) for the trait.

Use the following information to answer questions 4-9.

The trait for front hairline in humans is coded for by two different alleles: Genotype: Phenotype:

WW = widow’s peak or a distinct downward point of the frontal hairline

Ww = as aboveww = straight hairline

4) What are the possible genotypes for individuals who have a widow’s peak? _______________________

5) What is the only genotype for individuals who have a straight hairline? ___________________

6) What is the phenotype for an individual with the allele pair Ww? ____________________

7) Which of the above forms or alleles of the trait is dominant? (W, w) ______________

Define dominant: _______________________________________________________________________

______________________________________________________________________________________

8) Which of alleles is recessive? ________________

Define recessive: _______________________________________________________________________

______________________________________________________________________________________

9) Using the letters W and w, which of the allele pairs is homozygous dominant? __________

homozygous recessive? _________ heterozygous? ______________

10) If your big toe is longer than your second toe, you are considered homozygous recessive (bb) for big toe

length. If your big toe is shorter than your second toe, you could be either homozygous ______________(BB)

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or ________________________ (Bb) for the trait.

In the following questions, you can assume that the dominant allele is represented by a capital letter and the recessive allele is lower case.

11) If attached earlobes in humans is the recessive form of the trait (a) and free-hanging earlobes are dominant (A), fill in the genotypes and phenotypes of the following people:

Genotype: Phenotype:

homozygous dominant

homozygous recessive

heterozygous

a hybrid

a purebred (two answers)

In the following questions, you can assume that the dominant allele is represented by a capital letter and the recessive allele is lower case.

12) If S = black fur color in guinea pigs and s = white fur color, what is the phenotype of a guinea pig that is

homozygous recessive for coat color? ___________________

13) If G = green pea pod color and g = yellow pea pod color, what is the allele pair for a pea plant that is

heterozygous for pod color? ______________

14) If D = dimpled chin and d = smooth chin, what is the phenotype of an individual with the genotype Dd?

__________________________

Enough!! Let’s do some Punnett squares. Answer the following questions using either the foil method or the Punnet Square method:

15) Tall cucumber plants (T) are dominant to short (t) cucumber plants.

What are the predicted genotypes and phenotypes for the

offspring of two, heterozygous parents?

16) Cleft chin is dominant (H) to smooth chin (h).

What are the predicted genotypes and phenotypes for the offspring of

a homozygous recessive female and a heterozygous male?

17) Mrs. W is very proud that her curly hair (W) is dominant to straight hair.

One of Mrs. W’s daughter’s has curly hair but the other does not.

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If Mr. W is homozygous for the trait, what are Mrs. W’s and Mr. W’s genotypes?

CP Biology

HW #5: Genetics, Check Your Understanding

1. Define “allele”.

___________________________________________

2. In fruit flies, long wings (L) is dominant over short wings (l). Write the parents’ genotypes in the following Punnett Square or use FOIL to determine the genotypic and phenotypic outcomes.

Heterozygous x homozygous recessive. FOIL _______________________________

Genotypes:________________________

Ratio:_____________________________

Phenotypes:________________________

Ratio:_____________________________

_________3. In humans, having freckles (F) is dominant over no freckles (f). Therefore, FF is an abbreviation for:a. homozygous dominantb. heterozygousc. homozygous recessive

4. What would be the phenotype of the individual in question #3?

Matching. Match the word with the statement to the left that describes it.

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HW #6: THREE RULES FOR ONE-TRAIT CROSSES:

1) If both parents are homozygous for the same form of a trait, all offspring will be identical to the parents.2) Any cross in which at least one parent is homozygous dominant, will form offspring with the dominant phenotype.3) Any cross in which both parents have at least one recessive allele, will have some offspring that are homozygous recessive.

It isn’t always necessary to use FOIL or a Punnett Square. If you use the three rules of Monohybrid Crosses you can immediately answer the following questions. If you don’t believe it, use a Punnett Square or the FOIL method to check your work.

Use the following information to answer questions 1-3. Mendel studied the trait of pea seed shape. Smooth seeds (S) were dominant over wrinkled seeds (s).

1) Mendel cross pollinated two pea plants and all 250 of the offspring were smooth seeded. Which of the following crosses most likely represents the genotypes of the parents? (circle one)

a) SS x SS b) Ss x Ss c) ss x ss d) Ss x ss

Which rule(s) did you use? ____________

2) Mendel counted 98 wrinkled seeds and 102 smooth seeds in the F1 generation. Based on the ratio of the phenotypes produced, what were the probable allele pairs in the P1 cross?

b) SS x SS b) Ss x SS c) ss x ss d) Ss x ss

Which rule did you use? ____________

3) Mendel conducted another study and found that all the F1 seeds were smooth. Which of the following 10

______5. Homozygous a. The form of a trait that is always expressed if it is present.

______6. Pure Breeding b. The trait that is only expressed when the individual is homozygous for this gene pair.

______7. Hybrid c. Both alleles in a gene pair are identical.

______8. Dominant d. Another word for being homozygous.

______9. Recessive e. The two alleles in a gene pair are not identical.

______10. Allele f. One member of a gene pair/one form of a gene.

genotypes most likely represent the parents? (circle all that apply)

a) SS x SS b) SS x ss c) SS x Ss d) ss x ss

Which rule(s) did you use? ____________

Going Further: You can also use numbers of offspring to determine what type of cross the parents represent. Punnett squares are only a prediction of what the offspring will look like. The actual numbers will not be exact but should be close.

4) Which of the following would be the approximate number of smooth seeds compared to wrinkled seeds counted in the offspring of a cross between two pea plants that are heterozygous for seed shape.

a) 97 to 102 b) 103 to 50 c) 297 to 102 d) 103 to 25

CP Biology HW #7: One-Trait Crosses

Use the following Punnett squares to help answer the questions. Optional: You may fill in the results of each Punnett square or fill in by the FOIL method, if it will help to answer the questions. You can answer many of the questions simply using the 3 rules of one-trait crosses.

Lack of pigment deposition in the human body is an abnormal recessive trait called “albinism.” A human with albinism is called an albino. Many mammals display this same recessive trait such as deer, mice and rats. In the Punnett squares below, use A and a to represent the dominant (normal) allele and the recessive (albino) allele, respectively.

AA x aa Aa x Aa AA x Aa Aa x aa

FOIL : ________________ __________________ ________________ __________________

_______1. Which of the following is a cross between two purebred parents?a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

_______2. Which of the following is a hybrid cross?a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

_______3. Which cross predicts 100% heterozygous offspring?a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

_______4. Which cross predicts an F1 generation with a phenotypic ratio of 3:1, dominant to recessive?a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

_______5. Which cross predicts that all offspring would be homozygous recessive?a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

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_______6. Which two crosses predict that some offspring will be albino. (2 answers)a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

_______7. Which two crosses predict that all offspring will have normal pigment? (2 answers)a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

_______8. Which cross predicts a genotypic ratio of 1/4 :1/2 : 1/4, homozygous dominant to heterozygous, to homozygous recessive?

a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

______9. Which cross shows exactly that the parents first child will be albino, and their second will have normal pigmentation?

a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

______10. Which cross will predict that an offspring has a 50% chance of being albino?a. AA x aa b. Aa x Aa c. AA x Aa d. Aa x aa e. none of these

Bio CP HW #8: Monster One-Trait Crosses1) Green spots are dominant to yellow spots in dragon monsters. Two parents, heterozygous with green spots undergo sexual reproduction with each other.

______ ______ X ______ ______What percent of their offspring are predicted to have green spots? _______________ How many offspring out of 8 babies would be expected to have green spots? _____________ What is the genotypic ratio for the cross? _______________________

2) A baby monster with yellow spots grows up and mates with a male that is homozygous dominant with green spots.

______ ______ X ______ ______What is the genotype for all of their children? _________________What is the phenotype for their children? _______________

3) 2 horns are dominant to 1 horn in the dragon monsters. If a heterozygous male with 2 horns mates with a female with 2 horns and 5 babies are born, all with 2 horns, what is the most likely genotype for the parents?

______ ______ X ______ ______4) Forked tongues are dominant to rounded tongues. Two parent monsters with forked tongues have 6 babies. Four have forked tongues and only 2 have rounded tongues. What are the likely genotypes of the parents?

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______ ______ X ______ ______

5) Fire breathing is a recessive trait. The local wizard wishes to breed as many fire breathing monsters as possible. Which of the following crosses will give him the greatest number of fire breathing baby monsters? (circle your answer)

a) a heterozygous cross ______ ______ X ______ ______

b) a homozygous dominant crossed with a homozygous recessive ______ ______ X ______ ______

c) a heterozygous crossed with a homozygous recessive ______ ______ X ______ ______

6) THINK: The background scale color (behind the spots) comes in a dominant, blue form and a recessive, yellow form. If a heterozygous parent that has yellow spots mates with a homozygous recessive parent that has yellow spots, what color will the babies be? (Choose all that apply)

______ ______ X ______ ______

a) blue with green spots b) blue with yellow spots c) all yellow in colorIf the parents have 100 babies, how many would you predict to have each of the colors you chose above?

______________________________________ _____________________________________________

7) Wings (w) are special. They are also a recessive trait. Which of the following crosses will produce some babies with wings? (Circle your answer or answers.)

a) WW x ww c) Ww x Ww b) Ww x ww d) WW x Ww

8) Which of the following crosses would produce a 1:2:1 genotypic ratio in the offspring? (Circle your answer.)

a) WW x ww c) Ww x Ww b) Ww x ww d) WW x

Ww9) Which of the crosses below would show a 50% to 50% outcome in the genotypes and phenotypes of the offspring.

a) WW x ww b) Ww x ww c) Ww x Ww d) WW x Ww

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10) The wizard needs to conduct a test cross to determine the genotype of a male dragon with the dominant trait of pointed scales instead of the recessive form of round scales.

Which of the following females should he cross his male with to determine if the male is homozygous dominant or heterozygous? a) a female that has pointed scales b) a female with round scalesOnce the wizard has made the cross, he finds, to his surprise, that some of the babies have pointed scales and some have round scales. Based on his findings, what is the genotype of the male parent?

a) WW b) WwWhat were the genotypes of the parents? Male ______ ______ X ______ ______ FemaleBio CP HW #9: Two-trait Crosses

Use this information for questions #1-3 only. In some breeds of dogs a gene controls the characteristic of barking while tracking an animal. Another gene controls whether the ears are erect or drooping. Barking is dominant (B) to non-barking (b) and erect ears is dominant (E) to drooping ears (e).

______1 Which of the following pairs of alleles would be found in the egg cells of a dog that is homozygous dominant for barking and heterozygous for ear type?

a) BE and Be c) BB and Eeb) BE, Be, bE, be d) BB, Bb, EE, Ee

______2 What is the probability that offspring from a homozygous dominant barking, droopy eared male (BBee) and a heterozygous barking, droopy eared female (Bbee), will be non-barking with erect ears?

a) 0% b) 12.5% c) 25% d) 50% e) 100%

_____3) What is the genotype of a homozygous non-barking/heterozygous erect-eared dog?a) BBEe b) bbEE c) bbEe d) Bbee

Use the diagram at right for questions 4 & 5 only.

_____4) Given the following two-trait punnett square, what are the GENOTYPES of the parents?

a. FF x EE b. FfEe x FfEec. FEfe x FeFE d. cannot be determined

_____5) What is the probability of an offspring of genotype ffee from the cross shown at right?

a) 1/16 b. 9/16 c. 4/16 or ¼ d. 0/16

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_____6) If you were to cross two parents, genotypes GgWw x GgWw, which dihybrid punnett square below is set up properly to illustrate that cross?

Bio CP HW #10: Two Trait Parakeet Coloring

Parakeet body and wing colors are genetically controlled.

Gene 1 codes for a white body color with blue wings. There is no recessive allele for this gene. All birds are ‘BB’ for white body color with blue wings.

Gene 2 codes for an additional coloring across the body and the wings. This coloring combines with the original coloring to produce a combination of colors.The dominant allele ‘Y’ codes for a yellow coloring and the recessive allele ‘y’ codes for no additional coloring. It produces a non-functional protein.

______ 1) If a female parakeet is BByy, what color will she present on her body and wings?

a) white with blue wings b) yellow with blue wings c) yellow with green wings

______ 2) If a female parakeet is BBYy, what color will she present on her body and wings?

a) white with blue wings b) yellow with blue wings c) yellow with green wings

______ 3) Which of the following represents the gametes that could be produced by a white bodied, blue winged parakeet?

a) BY b) BB and YY c) BY and by d) By and bY

______ 4) What is the probability that a white bodied, blue winged female and a heterozygous, yellow bodied male will produce a white bodied, blue winged offspring?

a) 0% b) 25% c) 50% d) 75% e) 100%

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Red fruit (R) and stripes (T) are dominant to yellow fruit (r) and no stripes (t) in watermelon.

______ 5) A watermelon plant that is hybrid for fruit color and has no stripes is crossed with a plant that has yellow fruit and is hybrid for stripes. Which of the following shows the Punnett square that indicates the alleles in the gametes formed by the parent plants?

a) R t b) RT Rt c) rT rt R RT Rt

T Rt rt

______ 6) What is the probability that the two parent plants in question #5 could produce an offspring that has yellow fruit without any stripes?

a) 0% b) 25% c) 50% d) 75% e) 100%HW #11: One Trait Crosses Galore

Dimples:Use the following words or symbols to answer the questions below.

a. 1:2:1 b. 1:1 c. 3:1 d. none of thesee. 0% f. 25% g. 50% h. 75% i.

100%

______ 1) Two hybrid parents show the dominant phenotype: dimples. What is the predicted phenotypic ratio in their offspring?

______ 2) A homozygous dominant male with dimples has children with a heterozygous female. What is the predicted genotype of their offspring?

______ 3) What is the chance that a third child will have dimples, if a male without dimples has 2 dimpled children with a woman who is hybrid for the trait?

______ 4) What percent of babies will show the recessive phenotype if the parents are homozygous dominant and homozygous recessive.

Achondroplasia: Achondroplasia is one type of dwarfism in humans. It results from a DOMINANT ALLELE that causes a mutation in the fibroblast growth factor receptor gene. This causes an abnormality in cartilage formation which leads to severely shortened bones. Those affected call themselves, “achros.” Remember that a single, dominant allele causes dwarfism!Fill in the blanks with a single word in the parenthesis in the following questions.

5) If a male who is normal in size, has a child with a woman who is a homozygous “achro,” there is a

___________ ( 0, 25, 50, 75 or 100%) chance that the baby will be affected.16

6) Two parents can only have children who have the dominant phenotype. The father is heterozygous. The most likely genotype for the mother is _________________(AA, Aa, aa).

7) 75% of a parents’ offspring have dwarfism. The parents are both affected. Their genotypes are ______________________ (AA x aa, AA x Aa, Aa x aa, Aa x Aa, aa x aa).8) If the parent of an affected child does not have dwarfism, and the mother is hybrid, what is the chance that

their next child will be normal? ___________________ ( 0, 25, 50, 75 or 100%).

Earwax????? Wet type earwax is a dominant trait. The dry type is recessive. Asians and Native Americans are more likely to have the dry type whereas Caucasians and Africans more likely to have the wet type (honey-brown to dark-brown and moist). Ear wax type has been used to track human migratory patterns, such as those of the Inuit.

9) Two people have a child who has dry type earwax. What do you know about the two parents genotypes?

a) they each have a dominant allele c) neither is homozygous recessive

b) they are both heterozygous d) they both have at least one recessive allele

10) An Inuit male marries a Caucasian female. They have a number of children who have both wet and dry type earwax. If the Inuit has dry type earwax, what is the genotype of the mother?

a) homozygous recessive b) homozygous dominant c) heterozygous

Incomplete Dominance:

Merle color in dogs is caused by a gene pair that exhibits incomplete dominance. The merle allele causes white areas in the fur. Homozygous recessive (mm) dogs are normal in color, without white spots. Dogs that are homozygous dominant (MM) are mostly white. Heterozygous (Mm) dogs have random white areas in the coat.

11) Show a cross between the heterozygous dog to the right and a female that is colored the same. Show the genotypic and phenotypic ratios of their offspring.

Codominance: Roan Coloring in Cows and Horses

12)The roan coloring in cows is caused by a gene that produces white hairs intermixed with normal colored hairs. Show a cross between a normal colored red cow (CRCR) and a roan cow (CR CW). Include the genotypic and phenotypic ratios for the offspring.

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Blood Type:13) A baby mix-up happened at the hospital!!! Two baby boys lost their wrist tags and the nurses cannot figure out which parents they belong to. The nurses KNOW that each baby belongs to either of two sets of parents. They test the blood of the babies and find that one has type O blood while the other has type AB blood. Which parents to they belong to?

a) Two parents with type A and AB blood, respectively b) Two parents with type A and B blood, respectively

Type O baby belongs to __________________ Type AB baby belongs to _________________

CP Bio HW #12: One-Trait Crosses-Problem Packet Problem 1:

Trait That the Gene Codes For: presence or absence of dimplesForms of the Trait: DD = dimples present, homozygous dominant

Dd = dimples present, hybrid or heterozygous dd = dimples not present, homozygous recessive

List the six possible monohybrid crosses that can take place assuming you have male and female parents with each of the above genotypes. The first cross has been done for you.

1) ___DD x dd________ 2) _______________________ 3) ___________________________

4) ___________________ 5) ________________________ 6) ___________________________

Problem 2:

Trait: Earlobe shapeForms: FF = free hanging, homozygous dominant

Ff = free hanging, hybrid or heterozygous ff = attached, homozygous recessive

Use the multiplication method (FOIL) or draw a Punnett square toshow the possible genotypes and phenotypes for the offspring resulting from a cross between two hybrid or heterozygous parents. Include the ratios for geno- and phenotypes. Show your work.

F1 Genotypes ______________________________

F1 Phenotypes ______________________________

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Problem 3:

A tall pea plant is crossed with a short pea plant. All the offspring are tall. What is the genotype of the parents? Show your work.

Genotypes of P1: _____________________

Problem 4

Normal wing shape (N) in fruit flies is dominant to twisted wings (n). Two flies are mated. The female lays 99 eggs which hatch to form 24 flies with twisted wings and 75 with normal

wings. What are the probable genotypes of the parents? Show your work.

Genotypes of P1: _______________________Problem 5

Freckles are a dominant trait in humans. A parent who is homozygous for the trait has a child with a parent who is heterozygous or hybrid for the trait. What are the probable genotypes of both parents if all eight (yes, eight) of their children have freckles? Show your work.

Genotypes of Parents: ____________________________

Problem 6

A pea plant with green pods was crossed with a pea plant with yellow pods. Forty of 83 offspring had green pods. If green pod color is dominant, determine the genotypes of the parents. Show your work.

P1 Cross: ______________________

Problem 7

Trait: fur color in miceForms: BB = brown fur

Bb = brown fur bb = white fir

A brown female mouse is mother to 10 baby mice! The father mouse has white fur but all the babies have brown coats.What is the probable genotype of the mother mouse? Show your work.

Genotype of mother mouse: ____________________

Problem 8

Long eyelashes are dominant to short lashes. Two parents have the same genotype for eyelash length. Determine their probable genotypes if they have two children, one heterozygous with long lashes and one with short lashes? Show your work.

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P1 Genotypes: ______________________

Problem 9

Trait: hairlineForms: WW = widow’s peak homozygous dominant

Ww = w’s peak hybrid or heterozygous ww = straight hairline homozygous recessive

A man with a straight hairline marries a woman with a widow’s peak. Their first two children have a widow’s peak but the third has a straight hairline. What is the probability of their next child having a widow’s peak? Show your work.

Probability of next child with Ww: ___________________________Problem 10

Rough coats (R) in guinea pigs is dominant to smooth coats (r). Two rough-coated guinea pigs were mated and produced offspring that were all rough-coated. Three out of the six offspring were heterozygous. Determine the genotypes of the parents. Show your work.

P1 Cross: ________________

Problem 11

In squash, white fruit color is dominant to yellow fruit color. If a cross between a white-fruited plant and a yellow-fruited plant yielded 43 white and 39 yellow offspring, what is the white parent’s genotype? Show your work.

Genotype of white-fruited parent: __________________

Problem 12

Chromosome #15 contains a gene which normally codes for an enzyme that breaks down lipids. Without this enzyme, an individual develops Tay-Sachs disease. The disease is characterized by lipid buildup in the brain, severe disability and death by age four. The allele for the normal protein (P) is dominant while the allele for Tay-Sachs (p) is recessive. Determine the chances that a baby born from a homozygous dominant male and a heterozygous female might be born with Tay-Sachs disease. Show your work.

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What are the chances that a child from these parents will be born with the disease?

a) 0% b) 25% c) 50% d) 100%

Problem 13

Incomplete Dominance: Squash come in three different shapes, round (RR), long (rr) and bell-shaped (Rr, heterozygous form). Determine the genotypic and phenotypic results of crossing a long squash with a round squash.

Genotypic percent: ____________________

Phenotypic percent: ____________________Problem 14

Codominance: Shorthorn cattle show one of three different hair colors: red, white or roan. Roan is a combination of red and white hairs. This inheritance is symbolized by the following alleles: CR (red), and CW (white). A farmer breeds two adult shorthorns and, over a period of several years, records the following offspring: 4 red cows and 4 roan colored cows. What were the probable genotypes of the parents? Show your work.

P1 Genotypes: ________________________

Problem 15

Multiple Alleles and ABO Blood Grouping: Could a man with B type blood father a child with O type blood, if the mother has A type blood? Show your work.

Is it possible? _______________

Problem 16

X-Linked genes: A woman who is a “carrier” for hemophilia marries a normal man. What are the possible phenotypes of their children? Show your work.

F1 Phenotypes: Male children-_____________________ Female children: _____________________

Which of the children will be affected? __________________________

Which of the children will be unaffected? ________________________

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Which of the children will be carriers? __________________________

Problem 17

X-Linked genes: The gene that causes Duchenne muscular dystrophy (a recessive condition) is carried on the X chromosome. A woman who has the disease marries a normal man. What are the possible phenotypes of their children? Show your work.

F1 Phenotypes: ____________________________

What is a one-trait cross? ______________________________________________________________

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Mendel ReproductionDominant OO Recessive GeneticCounselorZygote CysticFibrosisSperm HuntingtonsEggs ObservedPunnett malesHeterozygous HemophilaHomozygous SickleCellPolygenic ExpectedKaryotype LowercasePurebred CapitalHybrid AmniocentesisFifty IncompleteDominance

GENETICSTest Review

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Across5. Disorders or conditions caused by X-linked recessive genes are more common in this sex.6. When writing a dominant gene, we use a __?__ letter.11. Results which are "predicted"12. Which genes are found in someone who has blood type O?14. A type of anemia in which some or all of the red blood cells are shaped like crescents; controlled by incomplete dominance17. Male reproductive cells which have half the body chromosome number19. A disorder caused by an X-linked dominant gene, which usually doesn't show its symptoms of damage to the brain until the patient is in his/her 30's/40's.20. The main purpose of a flower.21. a gene which is able to hide another form of the gene22. A disease in which the blood does not clot properly, due to an X-linked recessive gene.23. Female reproductive cells which have half the body chromsome number24. A synonym for 'heterozygous'27. a gene which can be hidden by another form of the gene28. A synonym for 'homozygous'Down1. Along with other techniques, such as ultrasounds and CVS, this technique is useful when looking for chromosomal abnormalities in a fetus.2. A disease caused by a recessive gene, which results in the production of a large amount of sticky mucus in the lungs, pancreas problems, and salty sweat.3. A trait which is coded for by more than one pair of genes, such as height or intelligence.4. A picture which shows the body chromosomes of an individual, arranged in 23 pairs.7. When writing a recessive gene, we use a __?__ letter.8. A fertilized egg9. the "Father of Genetics" who performed basic genetic crosses with pea plants10. A scientist who discusses genetic diseases with families.13. Results which are actually seen15. In a __?__ square, we are able to use the parents' genes to predict the possible genotypes of the offspring.16. Having two different alleles (copies of the gene) for a particular trait18. Having two of the same alleles (copies of the gene) for a particular trait25. A type of inheritance in which neither form of a gene is dominant or able to hide another form of that gene26. The expected chance of having a boy child is __?__%. (spell out the number)

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