Unit 6: Classical Genetics OLI Quizzes

A haploid organism has how many copies of each chromosome? a) 1 b) 2 c) 3 d) 4

a) 1

Huntington's disease is an autosomal dominant disorder. A person with the disorder and a person without the disorder mate. Both of these individuals are homozygous. What is the chance that the offspring will develop Huntington's? a) 100% b) 75% c) 50% d) 25%

a) 100% (If the parents are AA x aa, all the offspring will be Aa. Since Huntington's disorder is dominant, heterozygous individuals will develop the condition.)

Somatic mosquito cells have 6 chromosomes. How many chromosomes do gametes have? a) 3 b) 6 c) 12 d) 24

a) 3 (Somatic cells are diploid. Gametes are haploid and would have half the number of chromosomes.)

In dogs, colored fur (E) is dominant to un-colored fur (e). Black fur color (B) is dominant to brown fur color (b). The E gene is epistatic to the B gene. A yellow male dog is mated to a black female. The male's parents were both brown dogs. The female's mother was yellow, and her father was brown. What is the genotype of the female dog in this example? a) EeBb b) EEBb c) EEBB d) EeBB

a) EeBb (The female is black so she must have at least one E and at least one B allele. The female's mother was yellow, so she must have gotten an e allele. Her father was brown so she must have gotten a b allele.)

What would be the result of fertilization if egg and sperm were produced by mitosis rather than meiosis? a) The resulting offspring would have twice as much DNA as the parents. b) The resulting offspring would have the same amount of DNA as the parents. c) The resulting offspring would have half the amount of DNA as the parents.

a) The resulting offspring would have twice as much DNA as the parents. (Mitosis produces diploid cells. If a diploid egg and a diploid sperm fused, the resulting cell would be tetraploid.)

Nondisjunction in meiosis I results in a) Two cells missing a chromosome and two cells with an additional chromosome. b) Two cells with an additional chromosome and two healthy cells. c) One cell missing a chromosome, one cell with missing a chromosome and two healthy cells. d) Two cells missing a chromosome and two healthy cells

a) Two cells missing a chromosome and two cells with an additional chromosome. (Nondisjunction in meiosis I will result in no cells with the correct number of chromosomes.)

In beans yellow (Y) is dominant to green (y) and smooth (S) is dominant to wrinkled (s). What are the possible genotypes for the offspring of the following cross: YySS and YYSs? a) YYSS, YySS, YYSs, YySs b) YYSS, YYss, yySS, yyss c) YS, yS, YS, yS d) Yy, SS, YY, Ss

a) YYSS, YySS, YYSs, YySs (One parent produces gametes that are YS and yS, the other produces gametes that are YS and Ys. The punnet square results in YSS, YySS, YYSs, YySs for the possible gametes.)

Hemophilia is a recessive disorder and is on the X chromosome. Hemophilia is _____________________. a) found more often in males than females b) found more often in females than males c) equally common in males and females

a) found more often in males than females (Males only have one X chromosome while females have two, therefore males are more likely to develop the disorder.)

Alleles are different versions of a _______________. a) gene b) chromosome c) phenotype d) genotype

a) gene

An individual that expresses the recessive trait of a dominant/recessive gene a) must be homozygous b) must be heterozygous c) can be either homozygous or heterozygous

a) must be homozygous (Only aa will result in the expression of the recessive trait.)

Describe the importance of independent assortment: ________________________. a) will assort independently of each other b) will sort to the same gamete c) are called alleles d) All of these are true

a) will assort independently of each other (Chromosomes in meiosis assort independently, therefore the genes on separate chromosomes will assort independently.)

In humans, the condition for normal blood clotting (H) is dominant to hemophilia (h). A male who has normal blood clotting mates with a woman who is a carrier. If they have a daugher, what is the probability that she will have this condition? a) 100% b) 0% c) 75% d) 50%

b) 0% (The XHY x XHXh results in daughters that are either XHXH x XHXh (neither of which have the condition).)

In humans, how many alleles of genes found on the X chromosome do males have? a) 0 b) 1 c) 2 d) 4

b) 1 (Males have only one X chromosome.)

Red flower color is incompletely dominant to white flower color. Two red flowers are crossed. What percentage of their offspring will be red? a) 25% b) 100% c) 75% d) 50%

b) 100% (RR x RR produces 100% RR (red) flowers.)

In dogs, colored fur (E) is dominant to un-colored fur (e). Black fur color (B) is dominant to brown fur color (b). The E gene is epistatic to the B gene. A brown male dog is mated to a black female. Both the male and female are homozygous at all loci. What percentage of the puppies will be black? a) 50% b) 100% c) 75% d) 25% e) 0%

b) 100% (The male is EEbb and the female is EEBB. EEbb x EEBB results in 100% puppies that are EEBb (black).)

How many different gametes are produced by a cell with the genotype AABb? a) 1 b) 2 c) 3 d) 4

b) 2 (The possible gametes are AB or Ab.)

In humans, the condition for normal blood clotting (H) is dominant to hemophilia (h). A male who has normal blood clotting mates with a woman who is a carrier. If they have a son, what is the probability that he will have this condition? a) 100% b) 50% c) 75% d) 0%

b) 50% (The XHY x XHXh results in 50% of sons that are XHY (and do not have the condition) and 50% that are XhY (and do have the condition).)

In humans, the ability to roll the tongue (T) is dominant over the inability to do so (t). Suppose Mike, who can roll his tongue, and Jeannie, who cannot roll her tongue, have a child, Benjamin. If Mike's mother was able to roll her tongue but his father was not able to roll his, then what is the probability that Benjamin will be able to roll his tongue? a) 75% b) 50% c) 0% d) 100%

b) 50% (We know Mike is Tt, because he can roll his tongue but his father cannot. Therefore, there is 50% chance that Benjamin will inherit the T allele.)

Huntington's disease is an autosomal dominant disorder. If two individuals who are heterozygous at this locus breed, what are the chances that their offspring will develop Huntington's? a) 100% b) 75% c) 50% d) 25%

b) 75% (If the parents are heterozygous (Aa x Aa), the offspring will be 50% Aa and 25% AA (these will develop Huntington's). But, 25% of the offspring will be aa and will not develop Huntington's.

In beans yellow (Y) is dominant to green (y) and smooth (S) is dominant to wrinkled (s). What percentage of the offspring will be yellow and wrinkled in the following cross: Yyss and Yyss? a) 100% b) 75% c) 66% d) 50%

b) 75% (The Yyss genotype can occur in two different ways; either the male provides the Y and the female provides the y or the male provides the y and the female provides the Y. This genotype has a 50% possibility. The other yellow wrinkled genotype has another 25% possibility, for a total of 75%.)

In humans tongue rolling (T) is dominant to non-rolling (t). Two heterozygous individuals have a child. What is the probability that their child will be able to roll its tongue? a) 50% b) 75% c) 0% d) 100%

b) 75% (The male and female are both Tt. So, there is a 75% chance that the child will receive at least one T allele.)

The sister chromatids separate during which stage of meiosis? a) Anaphase I b) Anaphase II c) Prophase I d) Prophase II

b) Anaphase II (Homologous chromosomes separate in Anaphase I, but the sister chromatids remain attached until Anaphase II.)

Genotypes provide information about a) Carbohydrates b) DNA c) Lipids d) Proteins

b) DNA (Genotypes provide information about DNA; phenotypes provide information about proteins.)

In peas purple is dominant to white for flower color. A purple flower is crossed with a white flower. All the offspring (over 100 plants) produce purple flowers. What is the genotype of the purple flower? a) Pp b) PP c) pp d) Either PP or Pp

b) PP (All the offspring must have gotten a P from this parent and a p from the white parent.)

In peas, purple is dominant over white for flower color. Suppose a purple flower is crossed with a white flower. Some of the offspring are purple, and others are white. What is the genotype of the original purple flower? a) PP b) Pp c) pp d) either PP or Pp

b) Pp (The purple offspring are Pp; the white ones are pp.)

Red (R) flower color is incompletely dominant to white (r) flower color. Which cross will produce 100% pink flowers? a) White x White b) Red x White c) Red x Red d) Pink x Pink

b) Red x White

A nucleus is built around chromatids which have separated. This occurs during which stage of meiosis? a) Metaphase II b) Telophase II c) Metaphase I d) Telophase I

b) Telophase II (The individual chromatids separate during anaphase II and the nucleus rebuilds during telophase.)

Which of these discusses genotypes rather than phenotypes. a) The offspring of these flowers can be either red or white. b) The male mouse is homozygous dominant. c) Lactose intolerance can be due to a missing protein (the enzyme that digests lactose). d) All of these discuss genotypes

b) The male mouse is homozygous dominant. (Homozygous dominant is a term that describes the genetic makeup of alleles in an individual; this is genotype information.)

The condition of having an incorrect number of chromosomes is called ____________. a) nondisjunction b) aneuploidy c) trisomy d) epistatis

b) aneuploidy

Crossing over occurs: _______________. a) during meiosis II only b) during meiosis I only c) during mitosis but not meiosis d) during both meiosis I and meiosis II

b) during meiosis I only (Crossing over occurs when homologous pairs of chromosomes are paired during Mitosis I.)

Meiosis produces a) germ cells b) gametes c) somatic cells d) none of these

b) gametes

Homozygous is a term that can describe a(n) _____________. a) heterozygous b) genotype c) allele d) phenotype

b) genotype (A homozygous genotype is one in which the individual has two of the same allele.)

A female produces gametes a) that have either an X or a Y chromosome b) that have an X chromosome only c) that have a Y chromosome only d) That have 2 X chromosomes

b) that have an X chromosome only (Females are XX and produce gametes with an X chromosome.)

The sex of the offspring is determined by _____________. a) the mother only b) the father only c) both the mother and the father

b) the father only (The father is XY and can either produce gametes with an X chromosome (which will be female) or gametes with a Y chromosome (which will be male).)

In humans, there are 3 alleles for blood type: A, B, O. A and B are co-dominant over O. A male with O type blood mates with a female with AB type blood. What is the chance that their child will be heterozygous? a) 75% b) 0% c) 100% d) 25% e) 50%

c) 100% (OO x AB produces 50% AO and 50% BO, all of which are heterozygous.)

In beans yellow (Y) is dominant to green (y) and smooth (S) is dominant to wrinkled (s). What are the phenotypes for the offspring in the following cross: YySS and YYSs? a) 50% yellow smooth and 50% green smooth b) 100% green wrinkled c) 100% yellow smooth d) 50% yellow smooth and 50% yellow wrinkled

c) 100% yellow smooth (YYSS, YySS, YYSs, YySs all produce yellow and smooth seeds because yellow and smooth are both dominant.)

Two heterozygous individuals have mated. How many different genotypes can be present in the offspring? a) 1 b) 2 c) 3 d) 4

c) 3 (Crossing Aa with Aa produces the following possible offspring: AA, Aa, aa.)

Sickle cell anemia is an autosomal recessive disorder. A person with the disorder and a person that is a carrier mate. (A carrier has the allele for the trait but does not express it.) What is the chance that their offspring will develop sickle cell anemia? a) 100% b) 75% c) 50% d) 25%

c) 50% (A cross of Aa x aa produces 50% aa (who will develop the disorder) and 50% Aa (who will not develop the disorder).)

Red flower color is incompletely dominant over white flower color. If two pink flowers are crossed, what percentage of their offspring will be pink? a) 100% b) 75% c) 50% d) 25%

c) 50% (Rr x Rr produces 25% RR (red), 50% Rr (pink), and 25% rr (white) flowers.)

In dogs, colored fur (E) is dominant to un-colored fur (e). Black fur color (B) is dominant to brown fur color (b). The E gene is epistatic to the B gene. A yellow male dog is mated to a black female. The male's parents were both brown dogs. The female's mother was yellow, and her father was brown. What percentage of their puppies will be yellow? a) 100% b) 75% c) 50% d) 25%

c) 50% (The cross of EeBb x eebb produces 25% eeBb and 25% eebb - both of these are yellow. This cross also produces 25% EeBb (black) and 25% Eebb (brown).)

In dogs, colored fur, E, is dominant over colorless fur, e. Black fur color, B, is dominant over brown fur color, b. The E gene is epistatic to the B gene. Suppose a yellow male dog is mated with a black female. The male's parents were both brown. The female's mother was yellow, and her father was brown. What percentage of the puppies will be yellow? a) 100% b) 75% c) 50% d) 25% e) 0%

c) 50% (The male is eebb: ee because he is yellow, and bb because both his parents were brown. The female is EeBb. (We know she has at least one E allele because she is black, and she must be Ee because her mother was yellow, which implies ee. We also know the black female dog has a B allele because she has black fur, and a b because her father was brown.) EeBb x eebb results in 25% EeBb (black), 25% Eebb (brown), 25% eeBb (yellow) and 25% eebb (yellow).)

Red flower color is incompletely dominant over white flower color. If a red flower is crossed with a pink flower, what percentage of the offspring will be pink? a) 100% b) 75% c) 50% d) 25%

c) 50% (The pink flower donates the r allele and produces pink flowers 50% of the offspring.)

In dogs, colored fur (E) is dominant to un-colored fur (e). Black fur color (B) is dominant to brown fur color (b). The E gene is epistatic to the B gene. A yellow male dog is mated to a black female. The male's parents were both brown dogs. The female's mother was yellow, and her father was brown. What percentage of the puppies will be homozygous for the B gene? a) 100% b) 75% c) 50% d) 25%

c) 50% (This cross produces 25% Eebb and 25% eebb; these are both homozygous for the B gene.)

In humans, there are three alleles for blood type: A, B, and O. A and B are codominant over O. Suppose Jim, a man with type A blood, and Leah, a woman with type B blood, have a child, Winnie. Jim's parents both have blood type AB. Leah's mother has type B, and her father has type O. What is the probability that Winnie's blood type will be AB? a) 100% b) 75% c) 50% d) 25% e) 0%

c) 50% (We know Jim is AA, because he has blood type A and both his parents have AB. Leah's genotype is BO because her mother is B and her father was OO. AA x BO produces 50% offspring with AB type blood and 50% offspring with an AO genotype, which results in type A blood.)

In humans, there are three alleles for blood type: A, B, and O. A and B are codominant over O. Suppose Jim, a man with type A blood, and Leah, a woman with type B blood, have a child, Winnie. Jim's parents both have blood type AB. Leah's mother has type B, and her father has type O. What is the chance that Winnie's blood type will be A? a) 100% b) 75% c) 50% d) 25% e) 0%

c) 50% (We know Jim is AA, because he has blood type A and both of his parents have AB. Leah's genotype is BO, because her mother is B and her father was OO. AA x BO produces 50% offspring with AB type blood and 50% offspring with an AO genotype, which results in type A blood.)

List all possible gametes that can be produced from a cell that has the following genotype: AaBBDd. a) ABD, ABd, AbD, Abd, aBD, aBd, abD, abd b) A, a, B, D, d c) ABD, ABd, aBD, aBd d) ABD, abd

c) ABD, ABd, aBD, aBd (The cell is homozygous for the B gene, so combinations that include the b gene cannot occur.)

Peter gets his blood tested and finds out that he is B+. This test identified a a) Chromosome b) DNA c) Phenotype d) Genotype

c) Phenotype (Blood type is a genotype.)

In humans females are a) XY b) none of these c) XX d) YY

c) XX

In beans yellow (Y) is dominant to green (y) and smooth (S) is dominant to wrinkled (s). What are the possible genotypes for the offspring of the following cross: Yyss and Yyss? a) YYSs, YYss, YySs,YySs, Yyss, yySs, yyss b) YYSS, YYSs, YYss, YySS, YySs,YySs, Yyss, yySS, yySs, yyss c) YYss, Yyss, yyss d) YYss, yyss

c) YYss, Yyss, yyss

Linked genes: _______________________________. a) have related phenotypes b) sort independently of each other c) are found on the same chromosome d) are alleles of each other

c) are found on the same chromosome

A genetic disorder that is sex-linked cannot also be ___________________. a) all of these are possible b) recessive c) autosomal d) dominant

c) autosomal (Sex-linked refers to disorders found on the X or Y chromosomes, whereas autosomal disorders are not found on the sex chromosomes.)

Human height is affected by ______________. a) genetics only b) the environment only c) genetics and the environment

c) genetics and the environment

Hydrangeas are blue in acidic soil with available aluminum, and they are pink in alkaline soil without available aluminum, but they cannot be orange under any soil condition. The color of hydrangeas is affect by a) genetics only b) the environment only c) genetics and the environment

c) genetics and the environment

In humans, the ability to roll the tongue (T) is dominant over the inability to do so (t). Suppose Mike, who can roll his tongue, and Jeannie, who cannot roll her tongue, have a child, Benjamin. What is the probability that Benjamin will be homozygous dominant? a) 75% b) 100% c) 50% d) 0%

d) 0% (We know Jeannie is tt, because she cannot roll her tongue and tongue-rolling is a dominant trait. So Benjamin must have received at least one t allele.)

How many copies of each gene does a diploid organism have? a) 4 b) 3 c) 1 d) 2

d) 2 (A diploid organism has two of each chromosome, and therefore two of each gene.)

In dogs, colored fur, E, is dominant over colorless fur, e. Black fur color, B, is dominant over brown fur color, b. The E gene is epistatic to the B gene. Suppose a yellow male dog is mated with a black female. The male's parents were both brown. The female's mother was yellow, and her father was brown. What percentage of the puppies will be black? a) 100% b) 75% c) 50% d) 25% e) 0%

d) 23% (The male is eebb: ee because he is yellow, and bb because both his parents were brown. The female is EeBb. (We know she has at least one E allele because she is black, and she must be Ee because her mother was yellow, which implies ee. We also know the black female dog has a B allele because she has black fur, and a b because her father was brown.) EeBb x eebb results in 25% EeBb (black), 25% Eebb (brown), 25% eeBb (yellow) and 25% eebb (yellow).)

In dogs, colored fur, E, is dominant over colorless fur, e. Black fur color, B, is dominant over brown fur color, b. The E gene is epistatic to the B gene. Suppose a yellow male dog is mated with a black female. The male's parents were both brown. The female's mother was yellow, and her father was brown. What percentage of the puppies will be brown? a) 100% b) 75% c) 50% d) 25% e) 0%

d) 25% (The male is eebb: ee because he is yellow, and bb because both his parents were brown. The female is EeBb. (We know she has at least one E allele because she is black, and she must be Ee because her mother was yellow, which implies ee. We also know the black female dog has a B allele because she has black fur, and a b because her father was brown.) EeBb x eebb results in 25% EeBb (black), 25% Eebb (brown), 25% eeBb (yellow) and 25% eebb (yellow).)

Sickle cell anemia is an autosomal recessive disorder. If two heterozygous individuals breed, what is the chance that their offspring will develop Sickle cell anemia? a) 100% b) 75% c) 50% d) 25%

d) 25% A cross of Aa x Aa produces 25% aa (which will develop the disorder). It also produces 25% AA and 50% Aa (these will not develop the disorder.)

Two heterozygous individuals are crossed. What percentage of their offspring will be heterozygous? a) 25% b) 75% c) 100% d) 50%

d) 50% (Aa x Aa produces 50% homozygous (AA or aa) and 50% heterozygous (Aa) offspring.)

In humans, the ability to roll the tongue (T) is dominant over the inability to do so (t). Suppose Mike, who can roll his tongue, and Jeannie, who cannot roll her tongue, have a child, Benjamin. What is the probability that Benjamin will be homozygous recessive? a) 0% b) 100% c) 75% d) 50%

d) 50% (The male is Tt because his father is not able to roll his tongue. Therefore there is a 50% chance that Benjamin will inherit the t allele.)

A gene that encodes an enzyme required for ribose synthesis is found on the X chromosome. Females that are heterozygous for the wild-type and defective mutant allele of this gene will show: a) 100% of the enzyme activity in their cells, since the X-chromosome with the inactive gene will be condensed. b) 50% of the enzyme activity in their cells, since one allele is inactive. c) None of their cells will have the enzyme activity since the chromosome with the inactive allele will cause the other X-chromosome to become condensed. d) 50% of their cells will lack enzymatic activity, the other e) 50% will be active.

d) 50% of their cells will lack enzymatic activity, the other 50% will be active. (The condensation of the X-chromosome is random, the the activity present in the cell will depend on which X-chromosome is condensed. Half the cells will express the normal gene, the other half the defective gene.)

Which of the following is true of a diploid organism? a) It has two of each gene. b) It has two of each chromosome. c) It has two alleles of each gene. d) All of the above. e) None of the above.

d) All of the above. (A diploid organism has two chromosomes, two genes, and each gene has two alleles.)

What organism did Mendel study? a) Ants b) Roses c) Yeast d) Peas

d) Peas (Mendel used peas to determine some basic rules for inheritance.)

Which of the following is true of dominant traits? a) They are evolutionarily favorable. b) They are expressed only in homozygous dominant individuals c) They are more common in a population. d) They are expressed in both homozygous and heterozygous individuals.

d) They are expressed in both homozygous and heterozygous individuals. (Dominant traits are expressed in both homozygous and heteozygous individuals.)

In dogs, colored fur (E) is dominant to un-colored fur (e). Black fur color (B) is dominant to brown fur color (b). The E gene is epistatic to the B gene. A yellow male dog is mated to a black female. The male's parents were both brown dogs. The female's mother was yellow, and her father was brown. What is the genotype of the male dog in this example? a) ee b) eeBb c) eeBB d) eebb

d) eebb (The male parents were brown and would only have the b allele.)

Autosomal means that the gene is found on a) the X chromosomes b) the Y chromosome c) either the X or the Y chromosome d) neither on the X nor the Y

d) neither on the X nor the Y (Autosomal means it is found on a chromosome other than the sex determining chromosomes.)

A homozygous dominant germ cell undergoes meiosis. The gametes will _________________________. a) have both the dominant or the recessive allele b) only have the recessive allele c) either have the dominant or the recessive allele d) only have the dominant allele

d) only have the dominant allele (A homozygous dominant erm cell has 2 copies of the dominant allele, and no copies of the recessive allele.)

Genes on the X chromosome are called ______________. a) autosomal b) somatic c) epistatic d) sex-linked

d) sex-linked (Sex-linked genes are found on the sex determining chromosomes.)

In humans, there are three alleles for blood type: A, B, and O. A and B are codominant over O. Suppose Jim, a man with type A blood, and Leah, a woman with type B blood, have a child, Winnie. Jim's parents both have blood type AB. Leah's mother has type B, and her father has type O. What is the chance that Winnie's blood type will be B? a) 100% b) 75% c) 50% d) 25% e) 0%

e) 0% (We know Jim is AA, because he has blood type A and both of his parents have AB. Leah's genotype is BO, because her mother is B and her father was OO. AA x BO produces 50% offspring with AB type blood and 50% offspring with an AO genotype, which results in type A blood.)