Question 1

There is only a 1% variance between the genomes of human, Neandertals, and chimpanzees.

Accepted Answer

The statement is true because the genomes of humans, Neanderthals, and chimpanzees are very similar, with only a 1% variance. This means that the three species share a common ancestor and have evolved from each other relatively recently.

Question 2

The 20,000-25,000 human genes may encode more than 100,000 distinct mRNAs and proteins.

Accepted Answer

This statement is true. Alternative splicing, post-translational modifications, and other processes can lead to multiple variations of mRNA and protein products from the same gene.

Question 3

About half of the human genes identified by sequencing can be assigned a function by homology to previously characterized genes, and the other half represent new genes of unknown function.

Accepted Answer

This statement is true. About half of the human genes identified by sequencing can be assigned a function based on their similarity to previously characterized genes, while the other half are considered novel genes with unknown functions.

Question 4

More than 50% of the human genome is composed of various types of repetitive and duplicated DNA sequences.

Accepted Answer

This statement is true. Over half of the human genome consists of repetitive and duplicated sequences, which are believed to have accumulated over millions of years of evolution.

Question 5

Hybridization of fluorescent labeled cDNAs to microarrays of thousands of gene sequences allows gene expression to be assayed.

Accepted Answer

Hybridization of fluorescent labeled cDNAs to microarrays of thousands of gene sequences is a widely used method for gene expression analysis. The cDNAs represent the mRNA transcripts present in the sample, and their hybridization to the complementary probes on the microarray allows quantification of gene expression levels. Fluorescent labeling allows visualization and detection of the bound cDNAs, which can be used to infer the expression levels of the corresponding genes.

Question 6

Mass spectrometric identification of individual proteins in a complex mixture would be impossible in the absence of large-scale protein sequence databases.

Accepted Answer

Large-scale protein sequence databases are essential for identifying individual proteins in a complex mixture by mass spectrometry. The MS data can be compared to the database to identify the proteins by matching the peptide sequences obtained from the mass spectrometer to those in the database. Without such databases, it would be difficult to assign confident identities to the detected proteins.

Question 7

Hybridization of fluorescent labeled cDNAs to microarrays of thousands of gene sequences allows gene expression to be assayed.

Accepted Answer

Hybridization of fluorescent labeled cDNAs to microarrays of thousands of gene sequences is a widely used technique for gene expression analysis. It allows simultaneous detection and quantification of mRNA transcripts from thousands of genes.

Question 8

The computational analysis comparing the expression of all mRNAs between two different cells is an example of synthetic biology.

Accepted Answer

Computational analysis of mRNA expression is not an example of synthetic biology, but rather a technique used in various fields such as genomics, biotechnology, and medicine. Synthetic biology involves the design and construction of new biological systems or the modification of existing ones using engineering principles and techniques.

Question 9

If an organism has a 2 million base genome and 90% of it encodes proteins, and the average gene is 300 codons, how many genes does it have?

Accepted Answer

The answer of If an organism has a 2 million...

Question 10

Why would approximately 40% of the predicted human proteins be related to proteins in simpler organisms?

Accepted Answer

The answer of Why would approximately 40% of the predicted...

Question 11

Explain the likely effect that the sequencing of the human genome will have on medical science.

Accepted Answer

The answer of Explain the likely effect that the sequencing...

Question 12

What is the most significant difference between microarray analyses and RNA-seq analyses?

Accepted Answer

The answer of What is the most significant difference between...

Question 13

Even though there are only about 20,000 different protein-coding genes in humans, it is estimated that these give rise to more than 100,000 different proteins. What are two mechanisms that can account for this dramatic difference?

Accepted Answer

The answer of Even though there are only about 20,000...

Question 14

When carrying out immunoprecipitation experiments to investigate protein-protein interactions, why is it important to isolate the proteins under gentle conditions?

Accepted Answer

The answer of When carrying out immunoprecipitation experiments to investigate...

Question 15

You have two proteins you suspect of interacting with each other, but have an antibody to only one of them. Describe an experiment that might allow you to determine if the two proteins do indeed interact with each other.

Accepted Answer

The answer of You have two proteins you suspect of...

Question 16

You have identified a unique 8-base sequence in the promoter of a gene that controls growth. Describe an experiment that may address whether this sequence is capable of directing transcription of other genes.

Accepted Answer

The answer of You have identified a unique 8-base sequence...

Question 17

You have a cell signaling cascade in which a cell signal initially targets and activates protein 1 which in turn activates protein 2 which then activates protein 3 and finally activates protein 4. You are given a cell line that never expresses protein 2, yet in every experiment in which you give the initiating signal, you get activation of protein 4. How could you explain these results?

Accepted Answer

The answer of You have a cell signaling cascade in...

Question 18

In the pathway through which epinephrine signals the breakdown of glycogen to glucose in muscle cells, there are at least six different proteins involved before glycogen phosphorylase acts to cleave a glucose off of glycogen. Additional administration of epinephrine will increase the pathway. In a cell line in which phosphorylase kinase is mutated, what will happen if epinephrine is used to treat the cells?

Accepted Answer

The answer of In the pathway through which epinephrine signals...

Question 19

In which of the following organisms is the highest percentage of its genome used to encode protein?

Accepted Answer

Haemophilus influenzae has the highest percentage of its genome used to encode protein, with about 85% of its DNA devoted to protein-coding genes. In comparison, Saccharomyces cerevisiae has about 75% of its genome devoted to protein-coding genes, Drosophila melanogaster has about 60%, and Caenorhabditis elegans has about 50%.

Question 20

The main difference between the genomes of the bacteria Haemophilus influenzae and E. coli is that

Accepted Answer

The genome of E. coli is larger than that of H. influenzae, with E. coli having approximately 4.6 million base pairs compared to H. influenzae's 1.8 million base pairs.

Quiz 5: Genomics, Proteomics, and Systems Biology

There is only a 1% variance between the genomes of human, Neandertals, and chimpanzees.

The 20,000-25,000 human genes may encode more than 100,000 distinct mRNAs and proteins.

About half of the human genes identified by sequencing can be assigned a function by homology to previously characterized genes, and the other half represent new genes of unknown function.

More than 50% of the human genome is composed of various types of repetitive and duplicated DNA sequences.

Hybridization of fluorescent labeled cDNAs to microarrays of thousands of gene sequences allows gene expression to be assayed.

Mass spectrometric identification of individual proteins in a complex mixture would be impossible in the absence of large-scale protein sequence databases.

Hybridization of fluorescent labeled cDNAs to microarrays of thousands of gene sequences allows gene expression to be assayed.

The computational analysis comparing the expression of all mRNAs between two different cells is an example of synthetic biology.

If an organism has a 2 million base genome and 90% of it encodes proteins, and the average gene is 300 codons, how many genes does it have?

Why would approximately 40% of the predicted human proteins be related to proteins in simpler organisms?

Explain the likely effect that the sequencing of the human genome will have on medical science.

What is the most significant difference between microarray analyses and RNA-seq analyses?

Even though there are only about 20,000 different protein-coding genes in humans, it is estimated that these give rise to more than 100,000 different proteins. What are two mechanisms that can account for this dramatic difference?

When carrying out immunoprecipitation experiments to investigate protein-protein interactions, why is it important to isolate the proteins under gentle conditions?

You have two proteins you suspect of interacting with each other, but have an antibody to only one of them. Describe an experiment that might allow you to determine if the two proteins do indeed interact with each other.

You have identified a unique 8-base sequence in the promoter of a gene that controls growth. Describe an experiment that may address whether this sequence is capable of directing transcription of other genes.

In which of the following organisms is the highest percentage of its genome used to encode protein?

The main difference between the genomes of the bacteria Haemophilus influenzae and E. coli is that