Principles of Inheritance & Variation (Genetics) Questions and Answers

In peas, the allele for tall plants is completely dominant over the allele for short plants. The quickest way to determine whether a tall pea plant is homozygous or heterozygous is to cross it with another plant which is: There is no way to determine this. O homozygous tall O like itself O short O heterozygous tall

Tay-Sachs is an autosomal recessive disease, which causes deterioration of the nervous system and ultimately death in affected toddlers. Amniocentesis reveals that a fetus has Tay-Sachs disease. What are the genotypes of the parents if both parents are phenotypically normal? O Tt X Tt O TTXTT O tt X tt O Tt x tt O TTx Tt

In humans, red hair is recessive to dark hair. Dark-haired Sue is married to dark- haired Mike. Sue's father and Mike's mother have red hair. What is Sue's genotype? rr either RR or Rr Rr either Rr or rr RR

Which of the following genotypes is homozygous? RY Yy RR Rr

In humans, brown eyes are dominant over blue eyes. A blue-eyed child has the genotype Bb BB bb either Bb or BB impossible to tell

Albinism is an autosomal recessive trait. Is it possible for one albino parent and one pigmented parent to produce a normal-pigmented child? Yes Absolutely not No, unless there was a brand new mutation in the albino parent's gamete.

Domestic dogs can have either dominant straight (S/-) or curly hair (s/s), which can be dominant black (B/-) or yellow (b/b) in colour. Two dogs with the following genotypes were mated: S/s; B/b x s/s; b/b. (i) What is the probability of this cross producing an offspring that will phenotypically resemble either parent? Show your work. (ii) How many phenotypically different kinds of progeny could result from this cross? Show your work.

Which of the following are genetic disorders that affect human growth and development? Select all the correct options. a) Fetal Alcohol Syndrome b) Down's Syndrome c) Fragile X Syndrome d) Cystic Fibrosis

By conducting the given experiment, teacher can conclude that A.Genes for eye colour and body colour are linked. B.Genes for eye colour and body colour show complete linkage. C.Linked gene remain together and are inherited. a. A and B only b. B only c. A and C only d. A, B and C

What is known about the genetic components of autism? Select all that apply. Evidence of autism begins in the womb at 10-24 weeks of development. There are no genetic components. Autism is caused by vaccines. Autism can be hereditary or caused by a new gene mutation. Researchers know nothing about autism.

If the centromere on one of your chromosomes does not split properly at anaphase II of meiosis, the consequence would be the production of four cells -- two with 22 chromosomes and two with 24 chromosomes. each with 23 chromosomes. two with 46 chromosomes and two with 47 chromosomes two with 45 chromosomes and two with 47 chromosomes. two with 23 chromosomes, one with 22 chromosomes, and one with 24 chromosomes.

Polyploidy can result when a haploid sperm fertilizes a diploid egg. one pair of homologous chromosomes does not separate during meiosis. a translocation occurs between two chromosomes. a developing gamete is haploid.

An organism originally has a diploid number of 66 chromosomes. No meiosis occurs in this organism (gametes are diploid). Assume that the polyploid organism produced by union of the gametes is viable, and that the resulting organism also does not carry out meiosis. Also assume that this is true for future offspring of these organisms. If these organisms continue to mate, how many chromosomes will be found in a cell of the original organism's great grandchild? 528 33 132 O 1.056 O 66 264

Which of the following is an incorrect statement concerning the codon? It is a small sequence of DNA It is made up of three nucleotides It is the basic unit of the genetic code Each protein is coded for by one particular codon

Which of the following is a possible reason that the cell makes RNA as an intermediate to protein synthesis? RNA contains the information needed for the synthesis of proteins, this information cannot be found in the DNA DNA cannot pass out of the ribosome where it is stored. Being able to make many copies of RNA increases the rate at which proteins can be made Both A and C correct

Which of the following statements concerning DNA is false? Purines are larger structure than pyrimidines. Adenine and uracil are complementary bases. Adenine and guanine are purines. The number of cytosine molecule in DNA will always be equal to the number of guanine molecules.

Rosalind Franklin's x-ray diffraction images taken in the 1950s most directly support which of the following claims about DNA? (A) The ratios of base pairs are constant. (B) The nucleotide sequence determines genetic information. (C) The two strands of DNA are antiparallel. (D) The basic molecular structure is a helix.

Consider the following scenario. A farmer plants a huge grove of fig trees on their property. A large population of typical fig wasps (like the ones we discussed in class) moves in and starts laying eggs in the ripening figs. A biology student uses protein electrophoresis to examine the frequencies of two neutral alleles (A1 and A2) at some genetic locus in this population 1 generation after the fig wasps move in and again 10 generations after the fig wasps move in. If the population started with the following allele and genotype frequencies, frequency A1 = 0.5, frequency of A2 = 0.5, frequency of A1A1 = 0.25, frequency of A1A2 = 0.5, frequency of A2A2 = 0.25, which of the following results should the student predict will be more likely after 10 generations as a consequence of the effect of typical mating patterns in fig wasps? Select one: a. The requency of either A1 or A2 would drift to 1.0 and there would be no heterogygotes. b. The frequency of A1 and A2 would not change (or not change much), the proportion of heterozygotes would decrease and the proportion of homozygotes would increase. c.The frequency of A1 and A2 would not change (or change much) and all individuals in the population would be heterozygotes. d. The frequency of A1 and A2 would not change (or not change much), the proportion of heterozygotes would increase and the proportion of homozygotes would decrease

If light color is a dominant trait and the trees stay dark forever, could the light colored moths eventually become extinct? Why or why not?

The bison herd on Konza Prairie has begun to show a genetic defect. Some of the males have a condition known as "rabbit hock" in which the knee of the back leg is malformed slightly. This condition is controlled by a sex-linked gene and it is recessive. Now, suppose that the herd bull (the dominant one which does most of the breeding) who is normal (XN) mates with a cow that is a carrier for rabbit hock. Use the rules of probability. a) What are his chances of producing a normal son (bull)? b) If he mates with this cow every year, what percentage of their daughters will have normal knees? c) What percentage of their daughters will be carriers of rabbit hock?

If the pedigree below is for an autosomal recessive trait, what must be the genotypes of the parents in the P generation? A.) Aa x Aa B.) aa x aa C.) Aa x aa

If heterozygotes display a phenotype intermediate to homozygous dominant and homozygous recessive individuals A. the 2 alleles are codominant B. the 2 alleles are epistatically regulated C. the 2 alleles are incompletely dominant D. the 2 alleles are pleiotropic E. the alleles are control a polygenic trait

The following question is about the insulin-like growth factor 2 (Igf2) locus in mice. A homozygous dominant female is crossed with a homozygous recessive male. What would be the outcome of this cross if one of the gametes from the female is imprinted? 100% normal size 100% dwarf 1/2 normal size and 1/2 dwarf 3/4 normal size and 1/4 dwarf 1/4 normal size and 3/4 dwarf

Red color in tomatoes is dominant (autosomal gene) over yellow color. A farmer has a plant that produce red tomatoes. To determine the specific genotype of this red plant, the farmer crosses a yellow tomato plant and then looks at the next generation of fruit produced. If the original red tomato plant was heterozygous, what is the color of the next generation of fruit? cannot be determined yellow only some red, some yellow red only

Which of the following statements about gender development is not correct? A To be genetically male, one X chromosome and one Y chromosome are required. B. XY males will develop male sex organs without the presence of androgens. C. XX females can develop male sex organs in the presence of testosterone. D. The testis-determining factor gene on the Y chromosome stimulates the production of male hormones.

What is the expected genotypic ratio resulting from a heterozygous x heterozygous monohybrid cross? a 1:2:1 b 1:2 c 1:0 d 1:3:1

In analyzing the number of different BASES in a DNA sample (taken from a single organism), which of the following results--where each letter represents the quantity of that particular base--would be consistent with the base-pairing rules? "A" represents the quantity of Adenine. "T" represents the quantity of Thymine. "G" represents the quantity of Guanine. "C" represents the quantity of Cytosine. G+T=A A+T=G+C A+G=C+T A+G=A+T A+C=G A = G

If you compare two alleles of the same gene, you will see all the possible variation in that gene one will cause disease and the other will not one of the copies will always contain a SNV they will differ in sequence

1. Set up a punnett square using the following information: Dominate allele for smooth petals = S (Capital S) Recessive allele for wrinkled petals =s (lowercase s) Dominate allele for purple flowers = P (Capital P) Recessive allele for white flowers = p (lowercase p) Cross a homozygous dominant parent (SSPP) with a homozygous recessive parent (sspp)

Case Study #1 a. Robert has a widow's peak. b. Robert's father and paternal grandfather also have widow's peaks. c. Robert's mother and paternal grandmother do not have widow's peaks. d. Robert's maternal grandparents also do not have widow's peaks. Construct a Punnett Square for Robert's parents.

Now try a different way of solving a dihybrid cross. Because of Mendel's (second) law of independent assortment, you can work with the blood type gene and the hemoglobin gene separately. Set up two monohybrid crosses with the following parents: the mother is heterozygous for type B blood and has sickle cell trait, while the father has type AB blood and also has sickle cell trait. a. What are the chances that a child of this couple will have type B blood and sickle cell trait? b. What are the chances that a child will have type AB blood and will not have sickle cell disease? c. What are the chances that a child will have type B blood and sickle cell disease? d. What are the chances that a child will have type B blood and at least some normal hemoglobin? (Show your work.)

In a species, there is gene with two alleles. The frequency of the recessive allele is 0.81. Assume that the population is in Hardy-Weinberg equilibrium. What is the frequency of heterozygotes? Enter your answer as a percent (without the percent sign, decimals, or other notations--just the number).

Pregnant women have the option of being scanned for Cystic Fibrosis risks in their unborn babies. If a mother or a father have a certain recessive gene, the baby is at risk for Cystic Fibrosis. Given the three events, which of the following statements is true? Select all that apply. Event A: The mother or father carries the recessive gene. Event B: The father carries the recessive gene. Event C: The baby is at risk for Cystic Fibrosis. Select all that apply: Event A and Event B are mutually exclusive. Event B and Event Care mutually exclusive. Event A and Event Care not mutually exclusive. Event A and Event Care mutually exclusive.

Lupe grows pea plants in her garden. The pea plants have flowers that can be either purple or white, with purple color being dominant to white color. The peas produced by Lupe's pea plants can also be either round or wrinkled, with round peas being dominant to wrinkled peas. Lupe crosses two pea plants that are heterozygous for both traits. If a gamete from this cross receives a dominant allele for flower color, how does this influence the probability of the gamete receiving a dominant allele for pea shape? (Assume that the genes for flower color and pea shape follow the law of independent assortment.) A. It causes the gamete to be unable to receive a dominant allele for pea shape. B. It increases the probability that the gamete will receive a dominant allele for pea shape. C. It has no effect on the probability of the gamete receiving a dominant allele for pea shape. D. It decreases the probability that the gamete will receive a dominant allele for pea shape.

2. Define each of the following terms. Additionally, provide the phenotypes and genotypes of the A (A = dom, a rec) and B (B = dom, b = rec) genes of each individual/s involved that would accompany that particular term. dihybrid: dihybrid cross: dihybrid testcross:

In humans, brown eyes (B) are dominant over blue (b). A brown-eyed man marries a blue-eyed woman and they have three children, two of whom are brown-eyed and one of whom is blue-eyed. 11.) Draw the Punnett square that illustrates this marriage. 12.) What is the man's genotype? 13.) What are the genotypes of the children?

On a scratch piece of paper, use a Punnett square to complete a dihybrid cross between two parents with the following gametes: Male- SR, SR, Sr, and sr. Female- SR, SR, Sr, and sr. Determine the percentage of the offspring that will have a genotype of SSrr. 6% 18% 56% 100%

From the list below choose the three missing words from the following statement: Immunology examines the ___ and ___ interactions between a host and introduced ___ molecules. a. Self b. Atomic c. Neighboring d. Commensal e. Bodily f. Foreign g. Molecular h. Food i. Cellular

Mendel accounted for the observation that traits which had disappeared in the F1 generation reappeared in the F2 generation by proposing that _____. new mutations were frequently generated in the F2 progeny, "reinventing" traits that had been lost in the Fi the mechanism controlling the appearance of traits was different between the F1 and the F2 plants traits can be dominant or recessive, and the recessive traits were obscured by the dominant ones in the F1 generation members of the F1 generation had only one allele for each trait, but members of the F2 had two alleles for each trait

In cats, some are black, some are orange, and some are calico (fur that is both black and orange.) All calico cats are female. THis trait represents two inheritance patterns. List which two and explain how you know.

Chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. In some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. If these resistant individuals continue to survive and prosper, new resistant populations might emerge. (Please answer both A and B.) A. This would be an example of: a) genetic drift, b) natural selection, or c) the founder effect. B. Briefly explain why.

Cystic fibrosis affects the lungs, the pancreas, the digestive system, and other organs, resulting in symptoms ranging from breathing difficulties to recurrent infections. Which of the following terms best describes this? incomplete dominance pleiotropy multiple alleles epistasis codominance

A tall plant of unknown genotype is test-crossed (meaning it is crossed with a recessive tt plant). Of the offspring, 869 are dwarf and 912 are tall. What is the genotype of the unknown parent, is it TT or Tt? Show the cross to prove it.

Cystic fibrosis is an autosomal recessive mutation. Mary (c/c) who has cystic fibrosis is married to Jim (C/c) who has a normal phenotype. Mary and Jim have two children, the first child has cystic fibrosis (c/c), and the second child is unaffected (C/c). What is the probability that their third child will be a carrier (heterozygous) for the mutation that causes the disease?

In fish of the species Perissodus microlepis, some individuals have mouths that open to the right and some individuals have mouths that open to the left. The direction of the mouth opening is a genetic trait controlled by a single gene. The allele for a right-opening mouth (R) is dominant to the allele for a left-opening mouth (r). If two fish heterozygous for the mouth trait are crossed, what is the expected ratio of phenotypes in the offspring? A 1 right-opening mouth : 3 left-opening mouth B 2 right-opening mouth : 2 left-opening mouth C 3 right-opening mouth : 1 left-opening mouth D 4 right-opening mouth 0 left-opening mouth

SpongeBob SquarePants recently met SpongeSusie Roundpants at a dance. SpongeBob is heterozygous for his square shape, but SpongeSusie is round. Create a Punnett square to show the possibilities that would result if SpongeBob and SpongeSusie had children. HINT: Read question #2! A. List the possible genotypes and phenotypes for their children. B. What are the chances of a child with a square shape? out of ______or______% C. What are the chances of a child with a round shape? out of ______or______%

Incomplete Dominance - Snapdragon flower colors: Red (RR), White (R1R1), Pink (RR1). Cross the following snapdragon flower colors: Pink flower x Pink flower. How many of the offspring would be expected to be Red flower? A.) 0% B.) 25% C.) 50%

Which of the following statements is TRUE? O Only females develop symptoms in X-linked disorders O A chromosome count of 2n + 1 is an example of polyploidy O Dominant disorders are more rare than recessive disorders O Norms of reaction are broadest for qualitative traits O Epistasis occurs when one gene affects more than one character

A true-breeding plant with red flowers is crossed with a true-breeding plant with white flowers. Red (R) is completely dominant over white (r). What is the phenotype of the offspring? Red White rr RR Rr

In the cross AaBBDd x AABbDd What is the probability of getting AABBDD? You can use a scratch piece of paper to work out the problem, then answer the question. 16/64 24/64 4/64 12/64 20/64 8/64 28/64 32/64