Question 1

Explain the distinction between primary and secondary endosymbiosis.

Accepted Answer

Primary endosymbiosis is when descendants of a free- living species without endosymbionts evolves into the endosymbiont of another species. Secondary endosymbiosis is where a free- living species with its own endosymbiont(s) is enveloped by a second host species. After a period of gene transfer, the endosymbionts from the once free- living species become the endosymbionts of the second host, resulting in the transfer of endosymbiont genomes (mitochondria or chloroplasts) across phylogenetically- distinct host taxa.

Question 2

What are the closest "relatives" of chloroplasts still found as free- living organisms today?

Accepted Answer

cyanobacteria

Question 3

A consequence of organelle heredity is that sequence changes in mtDNA vary more than nuclear DNA in response to reduction in population size. Which of the following does this imply about human evolutionary history?

Accepted Answer

A)  Mitochondrial variants in people descending from originally small populations show enough diversity to be used to construct an evolutionary tree. 
B)  The original human population must have grown to be quite large before its members began migrating to other lands and other continents. 
C)  Nuclear gene sequencing must be used to resolve the question of human ancestral origins. 
D)  Current human populations must have a much higher mutation rate than ancient populations. 
E)  A single human population, living about 200,000 years ago, could not have given rise to all current human populations. 
A)  Mitochondrial variants in people descending from originally small populations show enough diversity to be used to construct an evolutionary tree. 
B)  The original human population must have grown to be quite large before its members began migrating to other lands and other continents. 
C)  Nuclear gene sequencing must be used to resolve the question of human ancestral origins. 
D)  Current human populations must have a much higher mutation rate than ancient populations. 
E)  A single human population, living about 200,000 years ago, could not have given rise to all current human populations. A

Question 4

If a chloroplast coding sequence has been transferred to the nuclear genome, but the protein product is needed in the chloroplast, what must be added to the original polypeptide sequence?

Accepted Answer

The answer of If a chloroplast coding sequence has been...

Question 5

In one or two words, give two characteristics of mitochondrial genomes.

Accepted Answer

Any two of the following:
Circ

Question 6

DNA transfer has occurred many times between organelle and nuclear genomes. Two pairs of nuclear and mitochondrial DNA sequences are analyzed. Pair A has more similarities than pair B. Which of these is the most ancient transfer?

Accepted Answer

The answer of DNA transfer has occurred many times between...

Question 7

The noncoding regions of mammalian mitochondrial genomes have little to no selective pressure. Which of the following are consequences of this condition?

Accepted Answer

A)  a rate of mtDNA repair is much lower than that of nuclear sequences 
B)  noncoding mitochondrial DNA increases in nucleotide diversity more quickly than coding DNA 
C)  a rate of mutation that can increase with successive generations in a maternal line 
D)  a high rate of natural selection for genomes identical to those of the mother 
E)  a high rate of loss of mitochondrial genomes relative to nuclear sequences 
A)  a rate of mtDNA repair is much lower than that of nuclear sequences 
B)  noncoding mitochondrial DNA increases in nucleotide diversity more quickly than coding DNA 
C)  a rate of mutation that can increase with successive generations in a maternal line 
D)  a high rate of natural selection for genomes identical to those of the mother 
E)  a high rate of loss of mitochondrial genomes relative to nuclear sequences

Question 8

The protein- coding genes of chloroplasts are involved in what part of photosynthesis?

Accepted Answer

oxidative

Question 9

Is the rate of mutation in mitochondrial DNA of mammals greater or less than that of the species' nuclear DNA?

Accepted Answer

The answer of Is the rate of mutation in mitochondrial...

Question 10

When a cell divides, chloroplasts are randomly distributed. What is this called?

Accepted Answer

replicativ

Question 11

How can you establish that, in a newly described species of plant, a particular phenotype is due to a chloroplast rather than a nuclear gene?

Accepted Answer

Mutations in chloroplast genes violate M

Question 12

Myoclonal epilepsy and ragged red fiber disease (MERRF) is a human condition named for the ragged red fibers of skeletal muscle cells and myoclonic epilepsy in affected individuals. People with this disorder have a mutation in a mitochondrial gene for a tRNA, specifically that for lysine. Affected individuals are heteroplastic. Why?

Accepted Answer

A)  Mutations of this gene are dominant. 
B)  Mutations of this gene affect individuals before birth. 
C)  Interference with translation is not fully rescued by importing lysine from the cytoplasm. 
D)  Lysine is required in translation of every one of the mitochondrial genes. 
E)  Homoplastic organelles would be inviable due to failures in translation. 
A)  Mutations of this gene are dominant. 
B)  Mutations of this gene affect individuals before birth. 
C)  Interference with translation is not fully rescued by importing lysine from the cytoplasm. 
D)  Lysine is required in translation of every one of the mitochondrial genes. 
E)  Homoplastic organelles would be inviable due to failures in translation.

Question 13

The human egg has about 2000 mitochondrial genomes, but somatic cells have a range of hundreds to thousands. Which of the following is most likely to account for the difference?

Accepted Answer

A)  Heteroplastic cells can give rise to homoplastic cells. 
B)  Haploid organelle genomes can replicate to form diploid or polyploidy genomes. 
C)  Mutant mitochondria replicate at different frequencies than do wild type. 
D)  Large mitochondria in oocytes can divide into many smaller mitochondria, and smaller mitochondria can replicate their DNA. 
E)  Somatic cells replicate their nuclear DNA at a faster rate than the oocyte. 
A)  Heteroplastic cells can give rise to homoplastic cells. 
B)  Haploid organelle genomes can replicate to form diploid or polyploidy genomes. 
C)  Mutant mitochondria replicate at different frequencies than do wild type. 
D)  Large mitochondria in oocytes can divide into many smaller mitochondria, and smaller mitochondria can replicate their DNA. 
E)  Somatic cells replicate their nuclear DNA at a faster rate than the oocyte.

Question 14

In mammals, the number of mitochondria per cell is highly variable. Which of the following would have the largest number: skin cells, red blood cells, or skeletal muscle cells?

Accepted Answer

skeletal m

Question 15

Which factor in organelle replication immediately precedes "organelle division"?

Accepted Answer

The answer of Which factor in organelle replication immediately precedes...

Question 16

Sequencing of genomes of eukaryotes, both mitochondrial and nuclear, have revealed evidence of sequence transfer from one to the other. Are such transfers ancient, recent, or both?

Accepted Answer

The answer of Sequencing of genomes of eukaryotes, both mitochondrial...

Question 17

In a plant, analysis of the Rubisco protein complex reveals that, in some complexes, rbcL is deficient while rbcS is normal. In other Rubisco complexes, both rbcL and rbcS are normal. What does this indicate about the two genes encoding these subunits?

Accepted Answer

rbcS is encoded by a nuclear gene while

Question 18

The plastids can differentiate into ___________that carry out photosynthesis.

Accepted Answer

The answer of The plastids can differentiate into ___________that carry...

Question 19

Variation in numbers of mutated chloroplast genomes can give rise to green, white, or variegated leaves. What color leaves do you expect in offspring of pollen from a white- leafed plant and ovules from a green- leafed plant?

Accepted Answer

The answer of Variation in numbers of mutated chloroplast genomes...

Question 20

What is the name of the area of the organelle in which organelle DNA is packaged?

Accepted Answer

The answer of What is the name of the area...

Explain the distinction between primary and secondary endosymbiosis.

What are the closest "relatives" of chloroplasts still found as free- living organisms today?

A consequence of organelle heredity is that sequence changes in mtDNA vary more than nuclear DNA in response to reduction in population size. Which of the following does this imply about human evolutionary history?

If a chloroplast coding sequence has been transferred to the nuclear genome, but the protein product is needed in the chloroplast, what must be added to the original polypeptide sequence?

In one or two words, give two characteristics of mitochondrial genomes.

DNA transfer has occurred many times between organelle and nuclear genomes. Two pairs of nuclear and mitochondrial DNA sequences are analyzed. Pair A has more similarities than pair B. Which of these is the most ancient transfer?

The noncoding regions of mammalian mitochondrial genomes have little to no selective pressure. Which of the following are consequences of this condition?

The protein- coding genes of chloroplasts are involved in what part of photosynthesis?

Is the rate of mutation in mitochondrial DNA of mammals greater or less than that of the species' nuclear DNA?

When a cell divides, chloroplasts are randomly distributed. What is this called?

How can you establish that, in a newly described species of plant, a particular phenotype is due to a chloroplast rather than a nuclear gene?

The human egg has about 2000 mitochondrial genomes, but somatic cells have a range of hundreds to thousands. Which of the following is most likely to account for the difference?

In mammals, the number of mitochondria per cell is highly variable. Which of the following would have the largest number: skin cells, red blood cells, or skeletal muscle cells?

Which factor in organelle replication immediately precedes "organelle division"?

Sequencing of genomes of eukaryotes, both mitochondrial and nuclear, have revealed evidence of sequence transfer from one to the other. Are such transfers ancient, recent, or both?

In a plant, analysis of the Rubisco protein complex reveals that, in some complexes, rbcL is deficient while rbcS is normal. In other Rubisco complexes, both rbcL and rbcS are normal. What does this indicate about the two genes encoding these subunits?

The plastids can differentiate into ___________that carry out photosynthesis.

Variation in numbers of mutated chloroplast genomes can give rise to green, white, or variegated leaves. What color leaves do you expect in offspring of pollen from a white- leafed plant and ovules from a green- leafed plant?

What is the name of the area of the organelle in which organelle DNA is packaged?

The Molecular Basis of Heredity, Variation, and Evolution

Transmission Genetics

Cell Division and Chromosome Heredity

Inheritance Patterns of Single Genes and Gene Interaction

Genetic Linkage and Mapping in Eukaryotes

Genetic Analysis and Mapping in Bacteria and Bacteriophage

Dna Structure and Replication

Molecular Biology of Transcription and Rna Processing

The Molecular Biology of Translation

Chromosome Chapter Title Tbd

Gene Mutation, Dna Repair, and Homologous Recombination

Chromosome Chapter Title Tbd

Regulation of Gene Expression in Bacteria and Bacteriophage

Regulation of Gene Expression in Eukaryotes

Analysis of Gene Function by Forward Genetics and Reverse Genetics

Recombinant Dna Technology and Its Applications

Organelle Inheritance and the Evolution of Organelle Genomes

Developmental Genetics

Genetic Analysis of Quantitative Traits

Population Genetics and Evolution at the Population, Species, and Molecular Levels

Filters

Exam 17: Genomics: Genetics From a Whole-Genome Perspective

Explain the distinction between primary and secondary endosymbiosis.

What are the closest "relatives" of chloroplasts still found as free- living organisms today?

A consequence of organelle heredity is that sequence changes in mtDNA vary more than nuclear DNA in response to reduction in population size. Which of the following does this imply about human evolutionary history?

If a chloroplast coding sequence has been transferred to the nuclear genome, but the protein product is needed in the chloroplast, what must be added to the original polypeptide sequence?

In one or two words, give two characteristics of mitochondrial genomes.

DNA transfer has occurred many times between organelle and nuclear genomes. Two pairs of nuclear and mitochondrial DNA sequences are analyzed. Pair A has more similarities than pair B. Which of these is the most ancient transfer?

The noncoding regions of mammalian mitochondrial genomes have little to no selective pressure. Which of the following are consequences of this condition?

The protein- coding genes of chloroplasts are involved in what part of photosynthesis?

Is the rate of mutation in mitochondrial DNA of mammals greater or less than that of the species' nuclear DNA?

When a cell divides, chloroplasts are randomly distributed. What is this called?

How can you establish that, in a newly described species of plant, a particular phenotype is due to a chloroplast rather than a nuclear gene?

The human egg has about 2000 mitochondrial genomes, but somatic cells have a range of hundreds to thousands. Which of the following is most likely to account for the difference?

In mammals, the number of mitochondria per cell is highly variable. Which of the following would have the largest number: skin cells, red blood cells, or skeletal muscle cells?

Which factor in organelle replication immediately precedes "organelle division"?

Sequencing of genomes of eukaryotes, both mitochondrial and nuclear, have revealed evidence of sequence transfer from one to the other. Are such transfers ancient, recent, or both?

In a plant, analysis of the Rubisco protein complex reveals that, in some complexes, rbcL is deficient while rbcS is normal. In other Rubisco complexes, both rbcL and rbcS are normal. What does this indicate about the two genes encoding these subunits?

The plastids can differentiate into ___________that carry out photosynthesis.

Variation in numbers of mutated chloroplast genomes can give rise to green, white, or variegated leaves. What color leaves do you expect in offspring of pollen from a white- leafed plant and ovules from a green- leafed plant?

What is the name of the area of the organelle in which organelle DNA is packaged?

The Molecular Basis of Heredity, Variation, and Evolution

Transmission Genetics

Cell Division and Chromosome Heredity

Inheritance Patterns of Single Genes and Gene Interaction

Genetic Linkage and Mapping in Eukaryotes

Genetic Analysis and Mapping in Bacteria and Bacteriophage

Dna Structure and Replication

Molecular Biology of Transcription and Rna Processing

The Molecular Biology of Translation

Chromosome Chapter Title Tbd

Gene Mutation, Dna Repair, and Homologous Recombination

Chromosome Chapter Title Tbd

Regulation of Gene Expression in Bacteria and Bacteriophage

Regulation of Gene Expression in Eukaryotes

Analysis of Gene Function by Forward Genetics and Reverse Genetics

Recombinant Dna Technology and Its Applications

Organelle Inheritance and the Evolution of Organelle Genomes

Developmental Genetics

Genetic Analysis of Quantitative Traits

Population Genetics and Evolution at the Population, Species, and Molecular Levels

Filters