The probability that matthew and jane’s first child will be an achondroplastic dwarf is

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Reproduction and Hereditary Unit

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The Elements of Life

In biology, the elements of life are the essential building blocks that make up living things. They are carbon, hydrogen, nitrogen, oxygen, phosphorus, and sulfur. The first four of these are the most important, as they are used to construct the molecules that are necessary to make up living cells. These elements form the basic building blocks of the major macromolecules of life, including carbohydrates, lipids, nucleic acids and proteins. Carbon is an important element for all living organisms, as it is used to construct the basic building blocks of life, such as carbohydrates, lipids, and nucleic acids. Even the cell membranes are made of proteins. Carbon is also used to construct the energy-rich molecules adenosine triphosphate (ATP) and guanosine triphosphate (GTP). Hydrogen is used to construct the molecules water and organic compounds with carbon. Hydrogen is also used to construct ATP and GTP. Nitrogen is used to construct the basic building blocks of life, such as amino acids, nucleic acids, and proteins. It is also used to construct ATP and GTP. Oxygen is used to construct the basic building blocks of life, such as carbohydrates, lipids, and nucleic acids. It is also used to construct ATP and GTP. Phosphorus is used to construct the basic building blocks of life, such as carbohydrates, lipids, and nucleic acids.

Questions 14-15refer to the following genetic terms(A) Codominance(B) Incomplete Dominance(C) Multiple alleles(D) Pleitotropy14. A red flower and a white flower produce a pink flowerB Incomplete dominance shows as a phenotypic blending of traits.15. A red flower and a white flower produce a red and white streaked flowerA In codominant inheritance both alleles are expressed.16. Hemophilia is a sex-linked recessive trait. A male hemophiliac and phenotypically normal femalehave a girl that is a hemophiliac. All of the following statements are correct EXCEPT:

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17. What is the likelihood that a couple will have 4 offspring all of which are female?

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18. Assume that a cross is made between AaBb and aabb plants and all of the offspring areeitherAaBb or aabb. These results are consistent with the following circumstance:A. Complete linkageB. Alternation of generationsC. CodominanceD. Incomplete dominanceAReason: Genes that are completely linked are so close together that recombination rarelyif ever occurs.19. Assume that a cross is made between AaBb plants and aabb plants and the offspring

occur in the following numbers: 106 AaBb, 48 Aabb, 52 aaBb, 94 aabb. These results areconsistent with the following circumstance:20. The recessive mutationss(scute bristles) andrb(ruby eyes) identify two linked

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Download Term 2 AP Biology Quiz Chapter 11 and 12 2014...

Quiz 2 T2 AP Biology Chapters 11 and 12 Name __________________________Date___________ Multiple Choice Questions (2 points each) 1. In garden peas, a single gene controls stem length. The recessive allele (t) produces short stems when homozygous. The dominant allele (T) produces long stems. A short-stemmed plant is crossed with a heterozygous long-stemmed plant. Which of the following represents the expected phenotypes of the offspring and the ratio in which they will occur? (A) 3 long-stemmed plants: 1 short-stemmed plant (B) 1 long-stemmed plant: 1 short-stemmed plant (C) 1 long-stemmed plant: 3 short-stemmed plants (D) Long-stemmed plants only B

Questions 2-3 A male fruit fly (Drosophila melanogaster) with red eyes and long wings was mated with a female with purple eyes and vestigial wings. All of the offspring in the F1 generation had red eyes and long wings. These F1 flies were test crossed with purple-eyed, vestigial-winged flies. Their offspring, the F2 generation, appeared as indicated below. F2 Generation 125 red eyes, long wings purple eyes, vestigial 124 wings 18 purple eyes, long wings 16 red eyes, vestigial wings 283 Total 2.

If in the F1 and F2 generations the same characteristics appeared in both males and females, it would be safe to assume that these traits for eye color and wing length (A) are sex-linked (B) vary in dominance according to sex (C) are sex-influenced characteristics (D) are autosomal characteristics

D 3.

In the F2 generation, the results are best explained by the fact that (A) the test cross with the F1 flies resulted in sterile offspring (B) these genes for eye color and wing shape do not pass through the F1 generation (C) these genes for eye color and wing shape are found on the same chromosome (D) crossing-over decreases variability

C 4. An allele on the X chromosome is responsible for the recessive trait of red-green color blindness in humans. The daughter of a woman who is color-blind has normal vision and marries a man who is color-blind. This couple has a son, what is the probability that the son will be color-blind? (A) 0 (B) 1/4 (C) 1/2 (D) 3/4 C

5. In the pedigree above, circles represent females, squares represent males, and shaded figures represent individuals expressing a specific trait. The expression of this trait is most likely due to which of the following? (A) Sex-linked dominant inheritance (B) Sex-linked recessive inheritance (C) Autosomal dominant inheritance (D) Autosomal recessive inheritance D Directions: Each group of questions below consists of five lettered headings followed by a list of numbered phrases or sentences. For each numbered phrase or sentence, select the one heading to which it is most closely related and fill in the corresponding circle on the answer sheet. Each heading may be used once, more than once, or not at all in each group. Questions 6-9 refer to the following genetic crosses, in which R and T represent dominant alleles and r and t represent recessive alleles for two genes that are located on different chromosomes. (A) TtRr x ttRr (B) TtRr x TtRr (C) TTRr x TtRR (D) TtRr x ttrr 6. Offspring from this cross are expected to exhibit a 1 : 1 : 1 : 1 phenotypic ratio. D 7. Offspring from this cross are expected to exhibit a 3 : 3 : 1 : 1 phenotypic ratio. A 8. All offspring from this cross are expected to exhibit both dominant traits.

C 9. This cross is an example of a dihybrid cross in which both parents are heterozygous. B 10. If a single locus controls wing shape, then the alleles for this gene act as (A) (B) (C) (D)

dominant-recessive alleles incomplete-dominance alleles codominant alleles multiple alleles

A Questions 11-13 refer to the following information. Achondroplastic dwarfism is a dominant genetic trait that causes severe malformation of the skeleton. Homozygotes for this condition are spontaneously aborted (hence, the homozygous condition is lethal) but heterozygotes will develop to be dwarfed. Matthew has a family history of the condition, although he does not express the trait. Jane is an achondroplastic dwarf. Matthew and Jane are planning a family of several children and want to know the chances of producing a child with achondroplastic dwarfism.

11. The genotypes of Matthew and Jane are best represented as Matthew Jane (A) AA Aa (B) Aa aa (C) aa aa (D) aa Aa D 12. The probability that Matthew and Jane’s first child will be an achondroplastic dwarf is (A) 0% (B) 25% (C) 50% (D) 75% C 13. If three children are born to Matthew and Jane, what are the chances that the first two children will not express the trait but that the third child will be an achondroplastic dwarf? (A) 5/8 (B) 4/8 (C) 3/8 (D) 1/8 D

Questions 14-15 refer to the following genetic terms (A) Codominance (B) Incomplete Dominance (C) Multiple alleles (D) Pleitotropy 14. A red flower and a white flower produce a pink flower B Incomplete dominance shows as a phenotypic blending of traits. 15. A red flower and a white flower produce a red and white streaked flower A In codominant inheritance both alleles are expressed. 16. Hemophilia is a sex-linked recessive trait. A male hemophiliac and phenotypically normal female have a girl that is a hemophiliac. All of the following statements are correct EXCEPT: (A) The daughter inherited a recessive gene from each parent. (B) The daughter inherited a dominant allele from her mother. (C) The mother is a carrier of hemophilia (D) The genotype of the mother is XH Xh B 17. What is the likelihood that a couple will have 4 offspring all of which are female? (A) 1/16 (B) ¼ (C) 1/3 (D) ¾ A

18. Assume that a cross is made between AaBb and aabb plants and all of the offspring are eitherAaBb or aabb. These results are consistent with the following circumstance: A. Complete linkage B. Alternation of generations C. Codominance D. Incomplete dominance A Reason: Genes that are completely linked are so close together that recombination rarely if ever occurs. 19. Assume that a cross is made between AaBb plants and aabb plants and the offspring occur in the following numbers: 106 AaBb, 48 Aabb, 52 aaBb, 94 aabb. These results are consistent with the following circumstance: A. Sex-linked inheritance with 30% crossing over B. Linkage with 50% crossing over C. Linkage with approximately 33 map units between the two gene loci D. Independent assortment C Reason: 48 + 52/ 300 = 33% = 33 map units 20. The recessive mutations s (scute bristles) and rb (ruby eyes) identify two linked autosomal genes of Drosophila melanogaster. When females heterozygous for these genes were crossed with scute bristled, ruby eyed males, the following classes and

numbers of progeny (out of 1000) were obtained: wildtype bristles, wildtype eyes 188 scute bristles, wildtype eyes 307 wildtype bristles, ruby eyes 313 scute bristles, ruby eyes 192 Based upon these results, the map distance between the s and rb genes is estimated to be: A. 31.3 map units B. 38 map units C. 30.7 map units D. greater than 50 units because all four classes of offspring were observed B Free Response Questions

1. A rooster with gray feathers is mated with a hen of the same phenotype. Among their offspring, 15 chicks are gray, 6 are black, and 8 are white. A. What is the simplest explanation for the inheritance of these colors in chickens? (5 points) Incomplete or codominance. Feather color is controlled by 2 genes B = black and b = white. The third phenotype is the result of a 50-50 mix of black and white to produce gray. The 15 gray, 6 black, and 8 white birds represent a 2:1:1 ratio&emdash;the result of mating two heterozygous individuals: (Bb x Bb)

1 BB : 2 Bb : 1 bb

B. What offspring would you predict from the mating of a gray rooster and a black hen? Punnett square to answer (5 points) A gray rooster (Bb ) mated to a black hen (BB ) can be represented by the following Punnett square:

50% of the offspring should be gray (Bb ) and 50% black (BB )

2. In some plants, a true-breeding, red-flowered strain gives all pink flowers when crossed with a whiteflowered strain: RR (red) x rr (white) ---> Rr (pink).

A. If flower position (axial or terminal) is inherited as it is in peas what will be the ratios of genotypes and phenotypes of the generation resulting from the following cross: axial-red (true-breeding) x terminalwhite? (5 points) Note: Axial (A ) is dominant over terminal (a ). The genotypes of the parents are AARR and aarr. Therefore the gametes of the parents must be AR and ar so the genotype for all the offspring in the F1 generation will be AaRr, and their phenotype will be axialpink.

B. What will be the ratios in the F2 generation? Use the Punnett square to answer(5 points) The ratio of genotypes can be determined by examining the Punnett square below:

The ratio of phenotypes will be: 6 axial-pink 3 axial-red 3 axial-white

8 pink 4 red 4 white

2 terminal-pink 1 terminal-white 1 terminal-red

12 axial 4 terminal

3. The recessive mutations m (mahogany eyes) and eb (ebony body) identify two autosomal linked genes of Drosophila melanogaster. When females heterozygous for these genes were crossed with mahogany eyed, ebony bodied males, the following classes and numbers of progeny (out of 1000) were obtained: wildtype eyes, wildtype body 370 mahogany eyes, wildtype body 130 wildtype eyes, ebony body 120 mahogany eyes, ebony body 380 Based upon these results, the map distance between the m and eb genes is estimated to be: Show all your work Answer: 25 map units. Reason: 130 + 120/1000 = 250/1000 = 25% 4. A newly identified fruit fly mutant, cyclops eye (large and single in the middle of the head), is hypothesized to be autosomal dominant. The experimenter started with homozygous wild type females (yes, virgins) and homozygous cyclops males. The data from the F2 generation was 44 wild type males, 60 wild type females, 110 cyclops males and 150 cyclops females. Does this data support or reject the hypothesis? Use chi square to prove your position. Once you have your answer check my answer below. Answer The chi square for the cyclops eye problem approximates 2.4 (depending on how your round your numbers) with one degree of freedom. The difference is insignificant and the hypothesis is accepted.

Explanation: Since it is hypothesized that cyclops eye is autosomal we can lump the wild type males and wild type females together (likewise for the cyclops flies). Therefore, we observed: 104 wild type flies and 260 cyclops flies

The expecteds for this problem are determined from the total number of flies observed 44 + 60 + 110 + 150 = 364

If Cyclops eye is in fact autosomal dominant 1/4 of the F2 generation should be wild type and 3/4 of the F2 generation should be cyclops eye. Therefore: 1/4 x 364 = 91 wild type flies expected, and 3/4 x 364 = 273 cyclops eye flies.

Filling out the X2 equation then: X2 = [(expected wild - observed wild)^2]/expected wild + [(expected cyclops - observed cyclops)^2]/expected cyclops X2 = [(91-104)^2]/91 + [(273-260)^2]/273 X2 = [(-13)^2]/91 + [(13)^2]/273 X2 =169/91 + 169/273 X2 =1.8 + 0.6 X2 = 2.4 Since there are two groups of data (and two terms) there are 2-1 = 1 degree of freedom. From the Chi-square table the standard must frequently used to divide significant from insignificant is 0.05 (5%) we can say that this deviation (difference) is insignificant.

What is the best explanation for the pink flowered offspring?

How would the extra chromosome affect the male offspring?

Which of the following represents a cross between a white eyed female and a red eyes male?

Which of the following best explains the differences in flower color of the African violets in the greenhouse?