Principles of Inheritance & Variation (Genetics) Questions and Answers

A scientist is trying to determine the relationship between clams, snails, and squid. When she generates a molecular clock, she is surprised to see that clams and squid are more closely related than clams and snails. Which did the molecular clock data show? Clams and squid have been evolving separately for a longer time than clams and snails. Clams and squid have been evolving separately for a shorter time than clams and snails. Clams and snails have more in common genetically than clams and squid. Clams and snails are more similar in related structures than clams and squids.

A woman has a rare Mendelian abnormality of the eyelids called ptosis, which prevents her from opening her eyes completely. This condition is caused by a dominant allele, Z. The woman's father had ptosis, but her mother had normal eyelids. Her father's mother had normal eyelids but his dad had ptosis. (To help answer the questions below, draw out the pedigree and add any known alleles/genotypes) a. What is the affected woman's genotype? Blank 1 b. What is genotype of the woman's father? Blank 2 c. What is the genotype of the woman's mother? Blank 3 d. What percentage of the woman's children will have ptosis if she marries a man with normal eyelids? Blank 4% Blank 1 Blank 2 Blank 3 Blank 4

The following statement are all false except for one a. Meiosis create genetic diversity during prophase I (crossing over) and anaphase I (independant assortment of homologous chromosomes) b. Meiosis create genetic diversity during prophase II (crossing over) and anaphase II (independant assortment of homologous chromosomes) c. During Anaphase II chromosomes only have 2 chromatids d. During Anaphase I chromosomes only have 1 chromatid e. Meiosis only create diploid cells which will be used during fertilization

Concordance refers to percentage of monozygotic twin pairs in which both express the trait. percentage of monozygotic twin pairs in which neither express the trait. percentage of twin pairs in which both express a trait among pairs in which at least one twin has the trait. percentage of dizygotic twin pairs in which both express the trait.

Heritability of a trait can change because the heritability in a family changes with the number of children. a person can consciously change her or his heritability. the environment can change. genes mutate.

In cats and rabbits, an autosomal recessive mutation causes soft curly fur, called the rex coat. The dominant allele R causes straight fur. An autosomal recessive mutation causes floppy ears, compared to the dominant straight ears (allele E). If rabbits Rr ee and rr Ee were mated, what are the chances that they will produce bunnies with rex coat and floppy ears? 1/4 3/4 3/8 9/16 3/16 1/16 0

Dimples is an autosomal dominant trait and no dimples is recessive. Brown eye color is autosomal dominant, and and blue eye color is recessive. If parents have Dd Bb and Dd bb genotypes, what is the chance that their child will have dimples and brown eyes? 1/8 1/4 3/8 5/16 9/16 3/16 0 1/16

Being right-handed is an autosomal dominant trait over being left-handed. Hitchhiker thumb is dominant over straight thumb trait. Mary is right-handed and has a hitchhiker thumb. Mary's mother is left-handed and has a hitchhiker thumb. Mary's father is right-handed and has a straight thumb. What is Mary's genotype? rrHh RrHh Rrhh RRHH none of these RRHH

In dogs, short fur is recessive and long fur is dominant in an autosomal gene F. The classic moustache and eyebrows seen in schnauzers is an autosomal dominant trait (use gene R). Suppose a breeder has a dog who is heterozygous for both genes. What gametes does this dog produce? fR rr ff Fr FFRR FR Ff Rr fr

A girl has dimples (dominant trait of autosomal gene D) and a cystic fibrosis (recessive disease from autosomal gene F). Which of these COULD be the genotype of her FATHER? Hint: Draw a pedigree. Mark all possible correct answers. DD FF Dd ff dd ff DD ff Dd FF dd Ff

Black fur in mice is dominant to brown fur. Short tails are dominant to long tails. In a cross of Bb Tt x bb Tt, what fraction of the offspring will have black fur and short tails? 1/16 1/4 1/8 3/4 3/16 9/16 3/8 0

Which are possible gametes of an organism that has Aa BB genotype? Genes A and B are autosomal. Mark all correct answers. AB Ab aB aa Aa ab bb Bb

In corn, red kernel color (R) is dominant to yellow (r) and smooth kernel texture (W) is dominant to wrinkled (w). Corn heterozygous for kernel color and kernel texture are fertilized with corn that is yellow and wrinkled resulting in the following phenotypic offspring were observed: red smooth; red wrinkled; yellow smooth; yellow wrinkled A chi-square value of 25.52 was calculated from the data collected. Answer the following questions: a. What is expected from the cross described? b. Why is this expected? c. Based on the chi-square value given above, state whether observations matched expectations by referring to p-value and probability. d. Do the data conform to Mendelian expectation? d. If observations do not match expectations, discuss two possible reasons why

The two interesting types of people who led researchers to discovery of the SRY gene were XXX females and XYY males. XY males and XX females. XX males and XY females. physicists and chemists.

A human male inherits an X chromosome from his mother and a Y chromosome from his father. his father's Y chromosome and an X chromosome from either his father or mother. an X chromosome from both parents. both X and Y chromosomes from his father.

Human females are the ________ sex. homogametic homozygous hemizygous heterozygous

A type of rickets is a X-linked dominant trait. A female heterozygous for rickets and an unaffected male are expecting a child. Determine the chances of this child inheriting this type of rickets. 0% 100% 25% 50% 75%

In humans, hemophilia is a X-linked recessive trait. If a female who is a carrier for hemophilia marries a male with normal blood clotting have a child together. Determine the possible genotypes of the child. Choose all that apply. XHXH xhxh XHY xHy xhy XHxh

Human males are the homozygous heterozygous homogametic heterogametic sex.

In humans, Ichthyosis is a X-linked recessive disorder that causes persistently dry, thickened, 'fish scale' skin. Rosa and Stefan's newborn son Alan has been diagnosed with the disorder. Rosa and Stefan do not have the disorder and do not know of anyone in their family with the disease. Which parent passed the disease allele to Alan? If Rosa and Stefan have another child, what is the risk of that child suffering from hemophilia? either Rosa or Stefan Rosa only Stefan only cannot be determined

Hemophilia is a sex-linked recessive condition that results in deficient blood clotting. The disease causes excessive bleeding which occurs spontaneously or upon slight injury. In dogs (as in humans) hemophilia is caused by a defect in a gene on the X chromosome.What will be the results of mating between a normal, non-carrier female dog and a male dog with hemophilia? Half the femaleoffspring will have hemophilia and half will be carriers, all male offspringwill be normal. All femaleoffspring will be normal and half the male offspring will have hemophilia. All the femaleoffspring will be normal and all male offspring will be carriers. All of theoffspring will be normal, but all females will be carriers. Half the maleoffspring will be normal and half will have hemophilia; all females will becarriers.

Which of these illustrates pleiotropy? the genes for red eyes and hairy body in fruit flies are located on the same chromosome human cystic fibrosis causes many symptoms from respiratory distress to digestive problems mating between earless sheep and long eared sheep results in short eared offspring wheat grains can range from white to red in color, a trait governed by multiple genes

Trevor's biologic mother has type A blood and his biologic father has type B blood. Based on this information, it is correct to say that: must have type A blood must have type AB blood must have type B blood could have type O blood

Your phenotype (hair color, eye color, blood type) is due to the specific __that your DNA codes the production of. Select one: a. RNA b. Carbohydrates c. Lipids d. Proteins

Allison has a newborn child that was the result of a sperm donor conceptions. She recently found out that the donor died from complications of neurofibromatosis type 1 (autosomal dominant). Her son tests negative for NF but she knows that the test has a 95% sensitivity and is not perfect. Group of answer choices 1/33 1/65 1/21

Cat fur color is determined by codominance. The allele for tan fur (TT) and the allele for black fur (BB) are codominant. The heterozygous condition (TB) results in a cat with tan and black spots, called a tabby cat. What would occur is a tan cat was crossed with a tabby cat? Draw the Punnett square and identify the genotypes and phenotypes of their offspring.

Duchenne muscular dystrophy is a sex-linked recessive trait like other sex-linked recessive traits such as Hemophilia or red/green color blindness that we talked about in class. Complete the following Punnett squares and questions associated with Duchenne muscular dystrophy. 2. Write the genotype of a woman who does not have Duchenne muscular dystrophy. 3. Write the genotype of a woman with Duchenne muscular dystrophy. 4. Write the genotype of a woman who is a carrier for Duchenne muscular dystrophy. 5. Write the genotype of a man who has Duchenne muscular dystrophy. 6. Write the genotype of a man who does not have Duchenne muscular dystrophy.

A long-eared mouse heterozygous for blue fur and homozygous recessive for the tailless condition is crossed to a blond mouse heterozygous for both a long tail and short ears. Using a branch diagram, determine the phenotypic ratio for the offspring. (dominant: Blue fur (B), tail present (T), short ears (E))

Note: Gender in fruit flies is determined by the composition of the sex chromosomes, X & Y; females are XX and males are XY. In fruit flies, a new mutant phenotype called wingless (i.e. a fly with no wings) is found to be a recessive phenotype, while having wings is the wildtype (and dominant) phenotype. This trait is X- linked. A female that is homozygous with wings is mated to a male fly that is wingless. The F1 are intercrossed to produce an F2 generation. what is the genotype of female? xt xt xw xw WW ++ xt xw

While doing a pedigree analysis of a royal family from the ancient Mayan empire, you notice that a prince with a genetic disease married a person from outside the royal family without a history of the disease in her family. Of their six children, two have the disease and four were not affected. The prince's mother and father also had this disease. If this disease is controlled by a single gene, then the most likely explanation for its occurrence in the children would be that the disease is: a spontaneous mutation. dominant and is only seen in homozygous dominant individuals. recessive and is only seen in homozygous recessive individuals such as the two affected children. dominant and is seen in heterozygous or homozygous dominant individuals.

You are attempting to determine the genotype of your C. bonita plant, which generates blush-colored blooms. A quick search tells you that pink blooms are the dominant phenotype; aqua blooms are the recessive phenotype for C. bonita blooms. Sadly, you don't have the capability to determine the genotype using DNA sequencing, but you can perform some mating experiments to help you determine the genotype of your blush- bloomed C. bonita plant. a) If the plant was homozygous dominant, which type of bloom color allele - blush, aqua, or either - would you expect to find in the gametes of your C. bonita plant? b) Using letters, define some alleles for bloom color in C. bonita. c) Now that we've got all that settled, you've decided to run a testcross to help you determine the genotype of your blush-bloomed; this means you'll mate your blush-bloomed plant with an aqua plant. Using all of the information you have and using the letters you've defined in part b, what would be the genotype of that aqua plant? d) You've completed your testcross and have some offspring - YAY! All of the offspring have blush- colored blooms. So, using those letters you've defined in part b, tell me the genotype of your parent blush-bloomed plant.

If you cross Pure agouti x pure black, what is/are the offspring phenotype(s)? all black 50% agouti, 50% black 75% agouti, 25% black all agouti

An X-linked recessive gene c produces red-green color blindness in men. A normal woman whose father was colorbling marries a colorblind man. a What genotypes are possible for the mother of the colorblind man? b What are the chances that the first child from this marriage will be a colorblind boy? c Of all the girls produced by these parents, what percentage is expected to be color blind? d Of all the children from these parents, what proportion is expected to be normal?

In humans, hemophilia is a sex-linked recessive trait. A female who is a carrier for hemophilia marries a male with normal blood clotting. If they do not know the gender of their expected baby, determine the chance that the child will have hemophilia? 50% 0% 100% Not enough information 25%

For rock pocket mice, which of the following contributes to selective pressure favoring dark-colored fur? (select all that apply) rock color genetic mutations predators availability of food for the rock pocket mice

When Watson and Crick were first proposing their model for DNA, they thought that the nitrogenous bases paired like with like (ie adenine with adenine). This turned out not to be feasible because it would cause all base pairing to be the same in length. the identical structure of the bases would not allow hydrogen bonding between them. the sequence of bases in the molecules would be affected. All of the above are correct.

The male-specific region of the Y chromosome lies between the two pseudoautosomal regions. has regions called amplicons that include few palindromic sequences. is completely identical to its counterparts on the X chromosome. has an abundance of protein-encoding genes.

In humans, having dimples in the cheeks is a dominant trait. If a child has dimples but only one of her parents does, what are the genotypes of her parents? (D = dimples; d = no dimples) One parent dd, other parent DD One parent dd, other parent Dd One parent Dd, other parent DD One parent must be DD, the other parent could be either dd or Dd One parent must be dd, the other parent could be either Dd or DD

The belief in the blending of traits was changed by Mendel's pea experiments. Mendel supported inheriting discrete. A. alleles B. DNA C. genes D. factors

Two plants are crossed, resulting in offspring with a 3:1 ratio for a particular trait. What does this suggest? that the trait shows incomplete dominance that the parents were true-breeding for contrasting traits that each offspring has the same alleles for each of two traits that the parents were both heterozygous for a single trait that a blending of traits has occurred

For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes? 920 46 460 23 about 8 million

Peas were a good organism of choice for Mendel because they cannot self-fertilize. they cannot cross-fertilize. the traits were difficult to visualize. he could study one trait at a time.

Which of the following did Mendel conclude about patterns of inheritance? An organism inherits one gene from each parent. The two genes of a given trait separate, or segregate, during gamete production. Similar forms of genes account for variation in the inherited traits. Organisms inherit one gene for each trait.

In cats, an autosomal dominant mutation R causes a rounded ear shape. An autosomal dominant mutation F causes feet with fewer toes. A male cat Ff RR mates with a female cat that is Ff Rr. What fraction of their offspring will have normal feet and rounded ears? 1/2 none of these 6/16 1/4 3/4

Select the correct answer. Jason adds the antibiotic penicillin to a bacterial culture. The bacteria develop genetic modifications in their genome, which gives them resistance to the antibiotic penicillin. What caused this genetic modification? A mutations to the DNA sequence B. normal gene regulation C. operon gene induction D. RNA interference

2.One variety of strawberry is resistant to a damaging fungus, but produces small fruit. Another strawberry variety produces large fruit, but is not resistant to the same fungus. The two desirable qualities may be combined in a new variety of strawberry plant by (1) cloning (2) asexual reproduction (3) direct harvesting (4) selective breeding

If all four heart valves are closed and the ventricular myocardium (heart muscle) is contracting the phase of the cardiac cycle is Diastole: sovolumetric contraction Systole, Isovolumetric contraction Diastole: Isovolumetric relaxation Systole. Isovolumetric relaxation

Height exhibits simple dominance, but petal color is incompletely dominant in xenon plants. If T= tall, t= dwarf, R= red, r= white, which genotype(s) would most likely express color other than white or red? A TTRr and TtRr B ttrr and TTRR C TtRR only

TT x tt All of the offspring in the F1 generation of the above cross would have the genotype. A tt B TT C Tt

RRYY x rryy What potential gametes can be produced by the dihybrid cross shown above? A. RY, RY B. Rr, Yy C. RY, ry