Chapter 10, Problem 1P

Summary Introduction

a.

To determine:

The phrase that describes “exome” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

The sequences of genomic DNA that possess exons are referred to as exome.

Answer to Problem 1P

Correct answer:

Exome: genomic DNA sequences containing exons

Explanation of Solution

The part of the genome that is composed of the exons is termed as the exome. The exons refer to the sequences tht remain intact along with the RNA even after the removal of introns.

Summary Introduction

b.

To determine:

The phrase that describes “de novo gene” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

Recently evolved genes from intergenic sequnces of DNA are called de novo gene.

Answer to Problem 1P

Correct answer:

de novo gene: recently evolved from intergenic DNA sequences.

Explanation of Solution

The gene that gets evolved from the intergenic deoxyribonucleic acid sequences is the de novo gene.

Summary Introduction

c.

To determine:

The phrase that describes “gene desert” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

The portion or region in the entire genome that shows lack of genes is called gene desert.

Answer to Problem 1P

Correct answer:

Gene desert: gene-poor region of the genome.

Explanation of Solution

In the genome the regions that lack protein-coding genes are termed as the gene desert. In the gene desert region since protein-coding genes are absent, so it is a gene-poor region of the genome.

Summary Introduction

d.

To determine:

The phrase that describes “pseudogene” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

Pseudogenes ar the genes that do not perform any kind of specific functions in the genome.

Answer to Problem 1P

Correct answer:

Pseudogene: a non-functional member of a gene family.

Explanation of Solution

The pseudogenes refer to the genes that are identical to the normal genes but these genes do not give rise to the functional genes, and therefore, are non-functional members of the gene family.

Summary Introduction

e.

To determine:

The phrase that describes “synthetic block” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

When two different species possess chromosomal regions having the same gene, it is said to be s syntenic block.

Answer to Problem 1P

Correct answer:

Syntenic block: chromosomal regions with same genes in the same order in two different species.

Explanation of Solution

In two different species, the similar or identical looking regions on the chromosome are said to have syntenic block. These blocks comprise of identical genes arranged in exact order in relatively distinct species.

Summary Introduction

f.

To determine:

The phrase that describes “orthologs” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

When gene possesses similarities in the sequences in the two different species, it is called orthologs.

Answer to Problem 1P

Correct answer:

Orthologs: genes with sequence similarities in two different species that arose from a common ancestral gene.

Explanation of Solution

The homologous genes that arise from a common ancestor and are present in different species are termed as orthologs.

Summary Introduction

g.

To determine:

The phrase that describes “natural selection” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

Selection of most advantageous species over recessive species.

Answer to Problem 1P

Correct answer:

Natural selection: progressive elimination of individuals whose fitness is low and survival of high fitness.

Explanation of Solution

The natural selection process refers to the process that helps an individual to adapt to its environment and reproduce. Only those organisms that are able to adapt to their surroundings will grow and reproduce.

Summary Introduction

h.

To determine:

The phrase that describes “consensus sequence” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

Themost frequent residues are called consensus sequence.

Answer to Problem 1P

Correct answer:

Consensus sequence: most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment.

Explanation of Solution

The consensus sequence refers to the arrangement of either nucleotides, residues or amino acids that frequently arise at each position in a sequence alignment.

Summary Introduction

i.

To determine:

The phrase that describes “gene family” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

The gene family possesses set of related genes.

Answer to Problem 1P

Correct answer:

Gene family: set of genes related by processes of duplication and divergence.

Explanation of Solution

The collection of genes that perform similar functions and consists of same sequences is termed as gene family. The gene families also comprise of ancestral genes that are either duplicated or diverged.

Summary Introduction

j.

To determine:

The phrase that describes “paralogs” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

Some genes are the result of duplication process that occurs within a particular species. Such genes are called paralogs.

Answer to Problem 1P

Correct answer:

Paralogs: genes that arose by duplication within species

Explanation of Solution

The paralogs refer to the set of genes that arise as a result of gene duplication that takes place within the species. These genes differ in terms of their function and composition.

Summary Introduction

k.

To determine:

The phrase that describes “alternative RNA splicing” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

When joining of exons in a particular gene results in the production of different combinations, this process is called alternative RNA splicing.

Answer to Problem 1P

Correct answer:

Alternate RNA splicing: the joining together of exons in a gene in different combinations.

Explanation of Solution

In the genes of eukaryotes, the rearrangement of exons to form new genes is termed as alternative RNA splicing. The alternative RNA splicing leads to formation of novel genes.

Summary Introduction

l.

To determine:

The phrase that describes “protein domain” among the options given below.

1. a discrete part of a protein that provides a unit of function.

2. a nonfunctional member of a gene family

3. the joining together of exons in a gene in different combinations

4. most frequent residues, either nucleotide or amino acid, found at each position in a sequence alignment

5. set of genes related by processes of duplication and divergence.

6. chromosomal regions with same genes in the same order in two different species.

7. genes with sequence similarities in two different species that arose from a common ancestral gene.

8. genes that arose by duplication within species.

9. genomic DNA sequences containing exons.

10. gene-poor region of the genome.

11. recently evolved from intergenic DNA sequences.

12. progressive elimination of individuals whose fitness is low and survival of high fitness.

Introduction:

When different combinations occurs due to rearrangement of exons, it is called protein domain.

Answer to Problem 1P

Correct answer:

Protein domain: the joining together of exons in a gene in different combinations.

Explanation of Solution

When the linear amino acid sequences bend and function as a single unit, it is termed as the protein domain. The rearrangement of exons to form different combinations result in protein domain.