Principles of Inheritance & Variation (Genetics) Questions and Answers

Following the Lederberg experiment, a scientist plated E. coli cells onto an agar plate with rich media and 125 colonies grew on this master plate. The scientist then replica printed the 125 colonies from the master plate onto two agar plates containing rich media plus the antibiotic kanamycin, which is known to kill E. coli cells. After an overnight incubation, the scientist observed a few antibiotic resistant mutant colonies growing on the same spots when comparing the two replica plates. What would explain these results? Some cells acquired antibiotic resistant mutations after they were grown in the presence of the antibiotic. All of the 125 colonies were antibiotic resistant before they were grown in the presence of the antibiotic. Some resistant mutants were present within the population of 125 colonies before they were grown in the presence of the antibiotic.

13. In hamsters, the CW allele produces a white-coat color phenotype. C is the wildtype allele and results in an orange coat color. A cross between a homozygous orange hamster with a white hamster results in 1:1 phenotype ratio of orange:white coat color in the progeny What can you conclude from this? A) orange fur color is dominant to white fur color B) the white parent is heterozygous C) the C gene is haplosufficient D) the C gene is temperature sensitive E) A and B

Which is true about mutations? A. They are always beneficial. B. They are always harmful. C. They are mostly neutral and unnoticed. D. They are always either beneficial or harmful.

How do we know that alleles actually separate during gamete formation? A. Scientists are unsure whether the alleles separate. B. If the alleles did not separate, recessive alleles would never reappear. C. Zygotes will not reach maturity if the alleles do not separate.

Assume brown eyes (B) are dominant to blue (b). A brown-eyed man marries a blue-eyed woman. They have three children, two of whom are brown- eyed and one of whom is blue-eyed. Draw the Punnett square that illustrates this family. What is the man's genotype? What are the genotypes of the children?

In pea plants, the trait for yellow seeds (Y) is dominant to that for green seeds (y). If a plant that is heterozygous for seed color is crossed with a plant that has green seeds, what are the expected genotypes of the offspring? Yy and yy in a ratio of 1:1 Yellow and green in a ratio of 3:1 Yellow and green in a ratio of 1:1 YY, Yy, and yy in a ratio of 1:2:1

What is the most important difference between nuclear DNA and mitochondrial DNA? Mitochondrial DNA does not use the same replication machinery as nuclear DNA There is no difference Mitochondrial DNA is inherited via ovum, whereas nuclear DNA comes from the ovum and the sperm Mitochondrial DNA is single-stranded and nuclear DNA is double-stranded

A plant that was homozygous recessive for seed shape and color was crossed with a plant that was heterozygous for seed shape. What percentage of the F1 generation will be heterozygous? RR: Round seeds Rr: Round seeds rr: Wrinkled seeds

Refer to #3b. A woman with sickle cell disease has children with a man who has sickle cell trait. What is the genetic makeup of the gametes the mother can produce? SS A S AA AS

1) For the scenario below, indicate which of the following "phenomena" is at work. More than one may apply. Co-Dominance - Epistasis - Incomplete Dominance - Pleiotropy - Polygenetic 2) Explain how you came to your answer. 3) Explain how/why the inheritance pattern differs from classic Mendelian inheritance. Jane is the child of 2 people who both have very dark skin, dark brown eyes and black hair. The skin, hair and eye coloring of Jane's 4 siblings very closely match her parents. Jane has albinism, a recessive condition that blocks the formation of the pigments associated with skin, hair and eye coloration.

Holandric genes are carried on the Y chromosome in men and have no analogous genes in women. A holandric gene is known in men, which causes long hair to grow on the external ears. When men with hairy ears marry normal women: a What percentage of their sons would be expected to have hairy eye? b What proportions of the daughters is expected to show the trait? c What ratio of hairy-eared:normal children is expected?

Variations in the ___ sequence of a gene can affect how quickly the encoded protein is synthesized. triplet palindrome promoter terminator anticodon

In watermelon, the allele for green rinds is completely dominant to the allele for striped rinds. You are given a melon with a green rind and asked to establish a pure-breeding line. How would you proceed?

The following parts of natural selection will be used to answer the next 4 questions. A. Differential Reproduction B. Overproduction C. Struggle to Survive D. Genetic Variation Which part of natural selection (see choices above) is described by the following sentence: More offspring can be produced than can survive to maturity.

Several answers can be correct. If this is the case you will need to check all the correct answers. A trait or a character a. is described by a word, either a noun or an adjective b. can be a physical characteristic, such as eye color c. is the expression of one or more genes d. is described by a letter, either a capital letter or a lowercase letter e. is known as the genotype

If the first child of the parents in problem 5 is feeble-minded, what is the probability that the second child will be feeble-minded? (This is akin to asking the question, if on a throw of the die, I threw a six, what is the probability that I will throw a 6 the second time? Note that this is a different question that what is the probability of throwing two 6's with two throws of the die.)

What will be the genotype(s) of the F, generation from the following parents? In what ratios? (Hint: first determine the types of gametes each parent can form, and then combine all the different types of gametes possible from one parent with all the different types of gametes possible from the other parent.) a BBFF x bbff b AaMM x AAmm c GgHh x gghh

Wood rats are medium sized rodents with lots of interesting behaviors. You may know of them as packrats. Let's assume that the trait of bringing home shiny objects (H) is controlled by a single locus gene and is dominant to the trait of carrying home only dull objects (h). Suppose two heterozygous individuals are crossed. How many of each genotype would be expected if only 4 offspring were produced?

In dogs, dark coat color is dominant to albinism, and short-haired coat is dominant to long-haired coat. a If a dog pure-breeding for dark, short-coat is crossed with an albino, long-haired dog, what genotypes and phenotypic ratios do you expect in their offspring? b If the pups are raised and then allowed to mate amongst themselves, what genotypes and phenotypic ratios do you expect in the offspring?

After transcription and before translation, eukaryotic mRNA is modified by adding a cap of modified nucleotides and a poly-A tail. an AUG at one end and a poly-U tail at the other. tRNAs and amino acids. amino acids and a poly-A tail.

In Guinea pigs, black hair (B) is dominant over white (b), rough coat texture (R) is dominant over smooth (r), and short hair (S) is dominant over long hair (s). Assume these genes are on separate chromosomes. a For a cross between a homozygous black, rough, short-haired Guinea pig and a white, smooth, long-haired one, what would the phenotype(s) of the offspring (F₁) be? b If two of the F, offspring were crossed, what would be the probability of getting a black, rough, short-haired pig in the F₂ generation?

A color blind male mates with woman who has normal vision. The woman has no history of colorblindness in her family.What percentage of their sons are expected to be colorblind? A) 25% B) 50% C) 75% D)100% E) 0%

Which organism that was the first to be used to relate the behavior of chromosomes during melosis to Mendel's principles of Segregation and Independent Assortment? (A) Garden peas (B) Summer squash C) Drosophila D Chickens E) Sweet peas

Two heterozygotes are mated in a monohybrid cross. What is the best description of the resultant offspring? 50% of offspring will have the dominant phenotype and 50% will have the recessive phenotype. 75% of offspring will have the recessive phenotype and 25% will have the dominant phenotype. All offspring will have the recessive phenotype. 75% of offspring will have the dominant phenotype and 25% will have

Where DNA replication occurs in animal cells adenine antiparallel chainreaction cytosine deoxyribose Franklin helix hydrogen leading nucleotide nucleus kazaki polymerase repair semiconservative

Please explain how type 4 collagen gene mutations result in appearance of proteins and blood cells in urine.

In cats, black fur color is caused by an X-linked allele; the other allele at this locus causes orange color. The heterozygote is tortoiseshell, which has black and orange fur. What kinds of offspring would you expect from the cross of a black female and an orange male? tortoiseshell females; black males orange females; black males tortoiseshell females; tortoiseshell males orange females; orange males black females; orange males

Two linked genes studied by Professor Barrett's lab control style length in a plant with an epistatic interaction, where long-styled plants are homozygous ssmm, mid-styled plants require at least one dominant Mallele, while the short-styled phenotype shows dominant epistasis where at least one S allele leads to the S morph. A cross is performed between an inbred short-styled SSMM plant and an inbred long-styled plant, and the F1 generation is backcrossed to a long-styled plant. If the two genes are 3 cM apart, what proportion of the progeny will have the mid-styled phenotype? A) 1.5% B) 3% C) 97% D) 98.5%

In pea plants, flowers can be purple (P) or white (p). In a field of peas, you count 13 plants with white flowers and 202 plants with purple flowers. A. What is the value of q? B. What is the value of p? C. What is the frequency of heterozygous plants in the field? D. Check your work, p²+2pq+q2-1 Are your numbers correct?

Which is not a good example of incomplete dominance? (A) A parent with red flowers and a aparent with white flowers produce a pink flower offspring.com B A parent with curly hair and a parent with straight hair produce a child with wavy hair.p C Two parents with green seed pods produce an offspring with green seed pods. D A parent with black wool and a parent with white wool produce an offspring with gray wool. €

Assume that person number 1 is homozygous for each trait and is male. Assume that person number 128 is female. What would be the characteristics of children born from a marriage between person number 1 and person number 128? Which parent would they most closely resemble?

Annette, an avid geneticist, crossed a male Siamese cat of genotype A/a; B/b; C/c; d/d; E/e with a female Siamese cat of genotype a/a; B/b; c/c; d/d; e/e. What is the probability of producing progeny with the mother's phenotypes at all loci? Assume independent assortment. A) 1/8 B) 1/16 C) 1/32 D) 3/32

6) A genetic map between three genes (A, B, and C) is shown below, where the degree of interference is known to be 0.5. A cross is performed between two parental strains of genotype AAbbCC and aaBBcc. If the F1 generation is then testcrossed to an aabbcc individual, what fraction of the offspring will be AaBbCc? A-------20 cM-------B-------40 cM--------C A) 0.02 B) 0.04 C) 0.8 D) 0.96

A gene in mice is known to show recessive lethality but also has dominant coat colour effects, where the presence of one copy of a particular allele will result in a yellow coat colour instead of the wild type black coat phenotype. A yellow coat-coloured mouse is crossed to an inbred black coat-coloured mouse. If two yellow coat-coloured mice from this cross are crossed to each other, what fraction of the offspring will have black coats? A) 1/4 B) 1/3 C) 2/3 D) 3/4

Evaluate the following statements, and select those that correctly apply to the properties of microscopes. The degree of contrast between a specimen and its surroundings is enhanced by the use of special stains and opening the iris diaphragm wide to allow in maximum light. When observing specimens with the 100x lens, adding a drop of oil to the slide will improve the resolving power; the image will be clear rather than blurry. Light rays with shorter wavelengths enhance the ability to resolve objects that are close together. If oil is not used with the 100x lens, the image will be less bright, compared to specimens observed with a drop of oil on the slide. If the 40x high-powered lens is used to view a specimen in conjunction with a 10X ocular, the total magnification of the specimen will be 50x.

A type of rickets is a X-linked dominant trait. If a female with rickets and an unaffected male have a daughter, what are the chances that the daughter will inherit this type of rickets? 100% 50% 0% 25% cannot be determined, as there is not enough information

Red-green Color-blindness is sex-linked recessive. Two parents with normal color vision have a color-blind child. Give the genotype of both parents. XDXD and XDY XDXd and XDXD xDxd and XDy xdxd and XDY

Mrs. Smith has a baby named Jessica. She believes one of two men can be the father of her child. A paternity test is done and the results are shown above. Which of the 2 men is the father of baby Jessica?

In his famous 1928 experiments, Griffith discovered the principle of transformation. He used strains of bacteria that killed mice () or ones that kept them alive (R). Which of the following experiments actually proved the transformation principle ? Heat killed mixed with live R killed the mouse. Heat killed S and heat killed R killed the mouse. Heat killed R mixed with live the mouse. Heat killed Skilled the mouse. Heat killed did not kill the mouse.

What conclusions can you draw from comparing the two graphs on page 4 of the worksheet? (select all that apply) In Arizona, there is no selective advantage to light- or dark-colored fur. In New Mexico, there is a selective advantage to having dark-colored fur In Arizona, different colored mice are equally fit and therefore equally likely to survive and reproduce. The fur color that makes a mouse more fit in their environment are more likely to survive and reproduce.

On page 4 of the worksheet, compare the two graphs, Mouse Population in New Mexico and Mouse Population in Arizona. What can be determined by the data? (select all that apply) The population of dark-colored mice in New Mexico is increasing The population of light-colored mice in New Mexico is decreasing. The population of light-colored mice in Arizona is decreasing. The population of dark-colored mice in Arizona is increasing

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