Deck 21: Genomics, Bioinformatics, and Proteomics

Question 1

Intron frequency varies considerably among eukaryotes. Provide a general comparison of intron frequencies in yeast and humans. What about intron size?

Answer 1

The entire yeast genome has only about 240 introns, whereas some single genes in humans contain more than 100 introns. In general, smaller genomes have smaller intron size in addition to lower intron number.

Question 2

Compared with eukaryotic chromosomes, bacterial chromosomes are ________.

A) large, mainly organized in single gene transcription units without introns
B) small, mainly organized in single gene transcription units with introns
C) large, mainly organized in polygenic transcription units without introns
D) small, with high gene density
E) large, triple-helix, Z-DNA, organized in single gene units with introns

Answer 2

D

Question 3

In general, the organization of genes in bacteria is different from that in eukaryotes. In E. coli, approximately 27 percent of all genes are organized into contiguous, functionally related units containing multiple genes under coordinate control that are transcribed as a single unit. Such contiguous gene families are called ________.

A) transcriptomes
B) proteomes
C) contigs
D) operons
E) pseudogenes

Answer 3

D

Question 4

Which two factors contribute significantly to the wide ranges of genome size among eukaryotes?

Question 5

One major difference between prokaryotic and eukaryotic genes is that eukaryotic genes can contain internal sequences, called ________, that get removed in the mature message.

Question 6

The human genome contains approximately 20,000 protein-coding genes, yet it has the capacity to produce several hundred thousand gene products. What can account for the vast difference in gene number and product number?

A) Alternative splicing occurs.
B) There are more introns than exons.
C) There are more exons than introns.
D) Much of the DNA is in the form of trinucleotide repeats, thus allowing multiple start sites for different genes.
E) Every gene can be read in both directions, and each gene can have inversions and translocations.

Question 7

What is one major limitation of two-dimensional gel electrophoresis (2-DGE)?

A) It is extremely costly to execute in a typical molecular biology laboratory.
B) When products are separated, they tend to leach out of the gel matrix.
C) Only the most abundant products are detected.
D) 2-DGE can be run only on nucleic acids.
E) 2-DGE is useful only in separating eukaryotic gene products.

Question 8

What is ELSI?

Question 9

Numerous scientists around the world have proposed to sequence 10,000 vertebrate genomes in five years. What is the name of this plan?

A) Genome 10K
B) Bigger Than Life Plan
C) 10K or Bust
D) Vertebrate Beginnings
E) Vertebrate Enlightenment

Question 10

The term paralog is often used in conjunction with discussions of hemoglobin genes. What does this term mean, and how does it apply to hemoglobin genes?

Question 11

Most of the bacterial genomes described in the text have fewer than ________.

A) 10,000 genes
B) 5000 base pairs
C) 500 genes
D) 10,000 base pairs
E) 50 genes

Question 12

What is meant by the term pseudogene?

Question 13

The Human Genome Project, which got under way in 1990, is an international effort to ________.

A) determine the base sequence of the human genome and to identify all the genes within
B) collect samples of cells from all parts of the world in order to preserve human genetic diversity
C) collect plant seeds in order to reduce the impact of human activity on plant extinction
D) clone deleterious genes from humans and study their mode of action
E) clone beneficial genes from humans for eventual use in gene therapy

Question 14

What is the typical gene density per kilobase in prokaryotes?

A) 426,000
B) 3000
C) 1200
D) 1
E) 12

Question 15

What appears to be the range of the number of protein-coding genes per genome in eukaryotes?

Question 16

A bacterial polygenic transcription unit ________.

A) contains information for one protein product
B) contains information for more than one protein product
C) is capped at the 5'end and carries a poly-A tail at the 3'end
D) is void of start (AUG) and termination (UAA, UGA, UAG) triplets
E) None of the answers listed is correct.

Question 17

Compared with prokaryotic chromosomes, eukaryotic chromosomes are ________.

A) large, mainly organized in single gene transcription units without introns
B) small, mainly organized in single gene transcription units with introns
C) large, mainly organized in polygenic transcription units without introns
D) small, mainly organized in polygenic transcription units without introns
E) large, linear, less densely packed with protein-coding genes, mainly organized in single gene units with introns

Question 18

What is meant by the term low gene density? Give an example of an organism with low gene density.

Question 19

Proteomics is the ________.

A) process of defining the complete set of proteins encoded by a genome
B) harvesting of proteins from a cell to determine their economic value
C) manipulation of amino acid sequences in proteins to alter their function
D) changing of the terminal sequences of proteins to alter their function
E) rational design of drugs based on protein structure

Question 20

Name the two strategic methods that scientists are using to sequence genomes.

Question 21

A number of generalizations can be made about the organization of protein-coding genes in bacterial chromosomes. First, the gene density is very high, averaging about ________.

Question 22

The genomic organization of all living creatures is identical.

Question 23

The dog (Canis familiaris) genome has recently been sequenced. About how many of the dog's genes are shared with humans?

Question 24

In what way will the discipline called metagenomics contribute to human health and welfare?

Question 25

Archaea (formerly known as archaebacteria) is one of the three major divisions of living organisms; the other two are eubacteria and eukaryotes. Speculate on how an organism such as Nanoarchaeum equitans with one of the smallest genomes known, about 0.5 Mb, can complete its life cycle with so little genetic material?

Question 26

Typically, bacterial DNA contains less repetitive DNA than eukaryotic DNA.

Question 27

Present an overview of the gene organization in large-genome plants.

Question 28

In humans, no genes are larger than 2 kb.

Question 29

Describe the organization of the α-globin gene in humans.

Question 30

It appears as if about 5000 functional genes is the minimum genome size necessary for life of a prokaryote.

Question 31

Present a general definition for a multigene family and how it relates to a superfamily.

Question 32

Sequencing the dog genome has indicated that a single locus on chromosome 15 may play a major role in genetically distinguishing large dog breeds from small dog breeds.

Question 33

The Human Genome Project is an international effort to construct a base sequence of the approximately 3 billion base pairs in the haploid human genome.

Question 34

Describe the relationship between introns (size and number) and organismic complexity in eukaryotes.

Question 35

How are pseudogenes formed?

Question 36

The terms proteomics and genomics mean essentially the same thing.

Question 37

What is comparative genomics?

Question 38

Introns are found only in prokaryotic genomes.

Question 39

Explain the goal of the emerging discipline called systems biology.

Question 40

Briefly describe general trends relating to DNA content and gene number in major groups of organisms.

Question 41

Bacterial genes have introns, and eukaryotic genes lack introns.

Question 42

Multigene families are characterized by clusters of tandemly arranged unique pseudogenes organized as operons.

Question 43

Humans have more DNA and more genes than any other organism.

Question 44

There is a general inverse relationship between DNA content and organismic complexity.