Question 1

The pedigree below shows the inheritance of a rare muscle condition in bats.What inheritance model best explains the peculiar pattern?

Accepted Answer

The condition is only passed on by affec

Question 2

You generated a plant that is heterozygous for three quantitative trait loci (QTL).In the heterozygous state,each locus has one allele that contributes one dose of trait (pigment)and another allele that does not contribute a dose to the trait;genotype: R1/r1;R2/r2;R3/r3.If you testcross this plant (by r1/r1;r2/r2;r3/r3 all "0-dose" alleles)what distribution of pigment doses would be observed in the progeny?

Accepted Answer

A) 1/8,three dose;3/8,two dose;3/8,one dose;1/8,zero dose 
B) 9/16,3 dose;3/16,2 dose;3/16,1 dose;1/16,0 dose 
C) 1/4,3 dose;1/4,2 dose;¼,1 dose;1/4,0 dose 
D) 1/2,2 doses;1/2,0 dose 
E) One hundred percent will be pigmented,equally. 
A) 1/8,three dose;3/8,two dose;3/8,one dose;1/8,zero dose 
B) 9/16,3 dose;3/16,2 dose;3/16,1 dose;1/16,0 dose 
C) 1/4,3 dose;1/4,2 dose;¼,1 dose;1/4,0 dose 
D) 1/2,2 doses;1/2,0 dose 
E) One hundred percent will be pigmented,equally.

Question 3

A male Drosophila melanogaster has the genotype A/a;B/b;C/c;XD/Y.How many different sperm genotypes can it produce through meiosis of one single pre-gametic (2n)cell?

Accepted Answer

A) 1 
B) 2 
C) 4 
D) 8 
E) 16 
A) 1 
B) 2 
C) 4 
D) 8 
E) 16

Question 4

A corn plant of genotype A/a;B/B;C/c;D/d;E/e;f/f;G/g is selfed.How many different completely homozygous genotypes could be produced?

Accepted Answer

A) 2 
B) 4 
C) 8 
D) 16 
E) 32 
A) 2 
B) 4 
C) 8 
D) 16 
E) 32

Question 5

In a plant in which 2n = 24,what is the total number of chromosomes present at the end of interphase?

Accepted Answer

A) 6 
B) 12 
C) 24 
D) 48 
E) 96 
A) 6 
B) 12 
C) 24 
D) 48 
E) 96

Question 6

A tomato plant with large leaves and round fruits was crossed to a plant with small leaves and oblong fruits.The F1 consisted of plants with large leaves;about half of these plants made round fruits and the other half made oblong fruits.Two F1 plants (one with round fruits and one with oblong fruits)were then analyzed through further crossing.The results were:

a)What are the genotypes of the two original parents?
b)What are the expected phenotypic ratios in the progeny of a cross between "F1 plant #1" and a tester?
c)What gamete genotypes can "F1 plant #2" produce?
Explain your reasoning behind each of your answers.

Accepted Answer

Since we don't know whether the original

Question 7

Suppose red-striped laughing frogs are diploid and have 32 chromosomes in somatic cells.Answer the following questions as they pertain to these vanishingly rare but beautiful creatures.
a)How many pairs of homologous chromosomes does a red-striped laughing frog have in its somatic cells?
b)How many chromosomes are there in a haploid set?
c)How many chromosomes are there in a mature sperm cell?
d)How many chromosomes are there in a somatic cell just after mitosis?
e)How many double-stranded DNA molecules are there in a somatic cell as mitosis is about to start?
f)How many chromosomes are there in a cell prior to DNA replication?

Accepted Answer

a)16
b)16

Question 8

Consider the following cross examining five unlinked genes.Identify what proportion of the progeny will be genotypically identical to parent 2?

Parent 1: A/a;B/b;C/c;D/d;E/e $\times$ Parent 2: A/A;b/b;C/c;D/d;E/e

Accepted Answer

A) 1/216 
B) 27/128 
C) 1/64 
D) 1/16 
E) 1/32 
A) 1/216 
B) 27/128 
C) 1/64 
D) 1/16 
E) 1/32

Question 9

What process occurring during meiosis ensures independent assortment?

Accepted Answer

A) the arrangement of homologous chromosomes on the metaphase plate 
B) the fusion of male and female gametes 
C) the pairing of homologous chromosomes in prophase 
D) the replication of DNA and formation of sister chromatids 
E) the "splitting apart" of sister chromatids in anaphase 
A) the arrangement of homologous chromosomes on the metaphase plate 
B) the fusion of male and female gametes 
C) the pairing of homologous chromosomes in prophase 
D) the replication of DNA and formation of sister chromatids 
E) the "splitting apart" of sister chromatids in anaphase

Question 10

If genes assort independently,a testcrossed dihybrid characteristically produces progeny phenotypes in the ratio:

Accepted Answer

A) 1:1 
B) 1:1:1:1 
C) 1:2:1 
D) 3:1 
E) 9:3:3:1 
A) 1:1 
B) 1:1:1:1 
C) 1:2:1 
D) 3:1 
E) 9:3:3:1

Question 11

A female Drosophila with singed bristles is crossed to a male with sepia (dark brown)eyes.In the F1,all females are wild type,and all males have singed bristles.F1 males and females are crossed together,and the following F2 phenotypic ratios are obtained.

748 wild-type females 
753 wild-type males 
742 singed females
747 singed males
249 sepia females
250 sepia males
244 singed, sepia females 
246 singed, sepia males

If sn and se represent the mutant alleles of the singed and sepia gene,respectively,and sn+ and se+ are their wild-type counterparts,what are the most likely genotypes of the original parents?

Accepted Answer

A) X/X;sn/sn;se+/se+ and X/Y;sn/sn+;se/se 
B) X/X;sn/sn;se+/se and X/Y;sn/sn+;se/se 
C) Xsn/Xsn+;se+/se+ and Xsn+/Y;se/se 
D) Xsn/Xsn;se+/se+ and Xsn+/Y;se/se 
E) Xsn/Xsn;se+/se and Xsn+/Y;se/se 
A) X/X;sn/sn;se+/se+ and X/Y;sn/sn+;se/se 
B) X/X;sn/sn;se+/se and X/Y;sn/sn+;se/se 
C) Xsn/Xsn+;se+/se+ and Xsn+/Y;se/se 
D) Xsn/Xsn;se+/se+ and Xsn+/Y;se/se 
E) Xsn/Xsn;se+/se and Xsn+/Y;se/se

Question 12

You just isolated a new strain of mutant mice,and preliminary matings suggest that the new mutant phenotype is not inherited autosomally.Circumstantial evidence seems to indicate that the mutant phenotype may be following either an X-linked dominant or a mitochondrial-type inheritance pattern.
a)What informative crosses would you set up to distinguish between these two possibilities?
b)How would you interpret your results?

Accepted Answer

a)affected female @#LAT-DLM& unaffected male
non-a

Question 13

Which diagram most accurately shows the arrangement of homologous chromosomes during the first metaphase of mitosis?

Accepted Answer

A)    
B)      
C)    
D)    
E)    
A)    
B)      
C)    
D)    
E)

Question 14

In a trihybrid,how many different gamete genotypes can be produced with respect to the three genes of interest?

Accepted Answer

A) 3 
B) 4 
C) 8 
D) 16 
E) 27 
A) 3 
B) 4 
C) 8 
D) 16 
E) 27

Question 15

Consider the following cross examining five unlinked genes.Identify what proportion of progeny will be phenotypically identical to parent 2?

Parent 1: A/a;B/b;C/c;D/d;E/e $\times$ Parent 2: A/A;b/b;C/c;D/d;E/e

Accepted Answer

A) 1/216 
B) 27/128 
C) 1/64 
D) 1/16 
E) 1/32 
A) 1/216 
B) 27/128 
C) 1/64 
D) 1/16 
E) 1/32

The pedigree below shows the inheritance of a rare muscle condition in bats.What inheritance model best explains the peculiar pattern?

A male Drosophila melanogaster has the genotype A/a;B/b;C/c;X^D/Y.How many different sperm genotypes can it produce through meiosis of one single pre-gametic (2n)cell?

A corn plant of genotype A/a;B/B;C/c;D/d;E/e;f/f;G/g is selfed.How many different completely homozygous genotypes could be produced?

In a plant in which 2n = 24,what is the total number of chromosomes present at the end of interphase?

Consider the following cross examining five unlinked genes.Identify what proportion of the progeny will be genotypically identical to parent 2? Parent 1: A/a;B/b;C/c;D/d;E/e $\times$ Parent 2: A/A;b/b;C/c;D/d;E/e

What process occurring during meiosis ensures independent assortment?

If genes assort independently,a testcrossed dihybrid characteristically produces progeny phenotypes in the ratio:

Which diagram most accurately shows the arrangement of homologous chromosomes during the first metaphase of mitosis?

In a trihybrid,how many different gamete genotypes can be produced with respect to the three genes of interest?

Consider the following cross examining five unlinked genes.Identify what proportion of progeny will be phenotypically identical to parent 2? Parent 1: A/a;B/b;C/c;D/d;E/e $\times$ Parent 2: A/A;b/b;C/c;D/d;E/e

The Genetics Revolution

Single-Gene Inheritance

Mapping Eukaryote Chromosomes by Recombination

The Genetics of Bacteria and Their Viruses

Gene Interaction

Dna: Structure and Replication

Rna: Transcription and Processing

Proteins and Their Synthesis

Gene Isolation and Manipulation

Regulation of Gene Expression in Bacteria and Their Viruses

Regulation of Gene Expression in Eukaryotes

The Genetic Control of Development

Genomes and Genomics

The Dynamic Genome: Transposable Elements

Mutation, Repair, and Recombination

Large-Scale Chromosomal Changes

Population Genetics

The Inheritance of Complex Traits

Evolution of Genes and Traits

Filters

Exam 3: Independent Assortment of Genes

The pedigree below shows the inheritance of a rare muscle condition in bats.What inheritance model best explains the peculiar pattern?

A male Drosophila melanogaster has the genotype A/a;B/b;C/c;XD/Y.How many different sperm genotypes can it produce through meiosis of one single pre-gametic (2n)cell?

A corn plant of genotype A/a;B/B;C/c;D/d;E/e;f/f;G/g is selfed.How many different completely homozygous genotypes could be produced?

In a plant in which 2n = 24,what is the total number of chromosomes present at the end of interphase?

Consider the following cross examining five unlinked genes.Identify what proportion of the progeny will be genotypically identical to parent 2? Parent 1: A/a;B/b;C/c;D/d;E/e ×\times× Parent 2: A/A;b/b;C/c;D/d;E/e

What process occurring during meiosis ensures independent assortment?

If genes assort independently,a testcrossed dihybrid characteristically produces progeny phenotypes in the ratio:

Which diagram most accurately shows the arrangement of homologous chromosomes during the first metaphase of mitosis?

In a trihybrid,how many different gamete genotypes can be produced with respect to the three genes of interest?

Consider the following cross examining five unlinked genes.Identify what proportion of progeny will be phenotypically identical to parent 2? Parent 1: A/a;B/b;C/c;D/d;E/e ×\times× Parent 2: A/A;b/b;C/c;D/d;E/e

The Genetics Revolution

Single-Gene Inheritance

Mapping Eukaryote Chromosomes by Recombination

The Genetics of Bacteria and Their Viruses

Gene Interaction

Dna: Structure and Replication

Rna: Transcription and Processing

Proteins and Their Synthesis

Gene Isolation and Manipulation

Regulation of Gene Expression in Bacteria and Their Viruses

Regulation of Gene Expression in Eukaryotes

The Genetic Control of Development

Genomes and Genomics

The Dynamic Genome: Transposable Elements

Mutation, Repair, and Recombination

Large-Scale Chromosomal Changes

Population Genetics

The Inheritance of Complex Traits

Evolution of Genes and Traits

Filters

A male Drosophila melanogaster has the genotype A/a;B/b;C/c;X^D/Y.How many different sperm genotypes can it produce through meiosis of one single pre-gametic (2n)cell?

Consider the following cross examining five unlinked genes.Identify what proportion of the progeny will be genotypically identical to parent 2? Parent 1: A/a;B/b;C/c;D/d;E/e $\times$ Parent 2: A/A;b/b;C/c;D/d;E/e

Consider the following cross examining five unlinked genes.Identify what proportion of progeny will be phenotypically identical to parent 2? Parent 1: A/a;B/b;C/c;D/d;E/e $\times$ Parent 2: A/A;b/b;C/c;D/d;E/e