Question 1

In John Gurdon's nuclear-transfer experiments, do you think he would have had more or less success if he had taken cells from a blastula? From an adult frog?

Accepted Answer

A) less; less 
B) less; more 
C) more; less 
D) more; more 
A) less; less 
B) less; more 
C) more; less 
D) more; more C

Question 2

Cells differentiate through:

Accepted Answer

A) growth. 
B) timing. 
C) gene regulation. 
D) the cell cycle. 
A) growth. 
B) timing. 
C) gene regulation. 
D) the cell cycle. C

Question 3

When pair-rule genes and segment-polarity genes are mutated, larvae display disturbances in segmentation patterns.

Accepted Answer

A) True 
 B)False  True

Question 4

Why has the development of iPS cells been viewed as a major breakthrough in the development of stem cell therapies?

Accepted Answer

A) It allows us to develop pluripotent stem cells without the ethical issues involved in obtaining them from human embryos. 
B) It may ultimately allow us to obtain stem cells from any individual-we can match the patient to the tissue. 
C) It is easy and inexpensive. 
D) It is a proven technique that we will be able to move into a clinical trial very quickly. 
E) It will allow us to "grow" new organs very quickly. 
A) It allows us to develop pluripotent stem cells without the ethical issues involved in obtaining them from human embryos. 
B) It may ultimately allow us to obtain stem cells from any individual-we can match the patient to the tissue. 
C) It is easy and inexpensive. 
D) It is a proven technique that we will be able to move into a clinical trial very quickly. 
E) It will allow us to "grow" new organs very quickly.

Question 5

In human development, cell rearrangement within the ball of cells leads to a hollow sphere with a "mound" of cells at one pole. This group of cells is called the:

Accepted Answer

A) mesoderm. 
B) blastocyst. 
C) neural plate. 
D) inner cell mass. 
E) gastrula. 
A) mesoderm. 
B) blastocyst. 
C) neural plate. 
D) inner cell mass. 
E) gastrula.

Question 6

Review Figure 20.19. Which floral organ develops from whorl 3 in Arabidopsis?

Accepted Answer

A) sepal 
B) carpel 
C) petal 
D) stamen 
A) sepal 
B) carpel 
C) petal 
D) stamen

Question 7

Which one of the following statements about homeotic, or Hox, genes is NOT correct?

Accepted Answer

A) Drosophila contain 8 Hox genes arranged in two clusters, the Antennapedia complex and the Bithorax complex. 
B) Hox genes are arranged in order according to their relationship with the anterior-posterior segmentation. 
C) Timing of expression corresponds to chromosomal order and location of expression. For example, anterior genes "turn on" earlier compared to those expressed in the posterior. 
D) The linear order of Hox genes along the chromosome, the anterior-posterior orientation of the embryo, and timing of expression for the genes in Hox clusters is observed only in Drosophila. 
E) Many of the genes in the mammalian Hox clusters have redundant or overlapping functions. 
A) Drosophila contain 8 Hox genes arranged in two clusters, the Antennapedia complex and the Bithorax complex. 
B) Hox genes are arranged in order according to their relationship with the anterior-posterior segmentation. 
C) Timing of expression corresponds to chromosomal order and location of expression. For example, anterior genes "turn on" earlier compared to those expressed in the posterior. 
D) The linear order of Hox genes along the chromosome, the anterior-posterior orientation of the embryo, and timing of expression for the genes in Hox clusters is observed only in Drosophila. 
E) Many of the genes in the mammalian Hox clusters have redundant or overlapping functions.

Question 8

In mammals, Hox genes:

Accepted Answer

A) specify limbs and other structures associated with each body segment. 
B) direct development of structures that become parts of the hindbrain, spinal cord, and vertebral column. 
C) evolved by partial-genome duplication from the ancestral genes. 
D) are expressed in a sequence that does not reflect their linear order in the chromosome or the regions they affect. 
E) All of these choices are correct. 
A) specify limbs and other structures associated with each body segment. 
B) direct development of structures that become parts of the hindbrain, spinal cord, and vertebral column. 
C) evolved by partial-genome duplication from the ancestral genes. 
D) are expressed in a sequence that does not reflect their linear order in the chromosome or the regions they affect. 
E) All of these choices are correct.

Question 9

Examine the figure and statements below. Which of the statements is INCORRECT?

Accepted Answer

A) mRNA for caudal and hunchback are evenly distributed in the oocyte, but bicoid and nanos mRNA are located either anteriorly or posteriorly, respectively. 
B) Bicoid protein promotes the transcription of the hunchback gene in the anterior region of the embryo. 
C) Nanos protein represses the translation of hunchback mRNA in the posterior region of the embryo. 
D) Bicoid protein represses the translation of caudal mRNA in the anterior region of the embryo. 
E) The expression pattern of Caudal and Hunchback proteins is an example of gene regulation at the level of translation. 
A) mRNA for caudal and hunchback are evenly distributed in the oocyte, but bicoid and nanos mRNA are located either anteriorly or posteriorly, respectively. 
B) Bicoid protein promotes the transcription of the hunchback gene in the anterior region of the embryo. 
C) Nanos protein represses the translation of hunchback mRNA in the posterior region of the embryo. 
D) Bicoid protein represses the translation of caudal mRNA in the anterior region of the embryo. 
E) The expression pattern of Caudal and Hunchback proteins is an example of gene regulation at the level of translation.

Question 10

Which of the following statements about the development and function of the visual system in animals is INCORRECT?

Accepted Answer

A) The light-sensitive molecule for all light-sensing cells is the same, a derivative of vitamin A complexed with a protein called opsin. 
B) Eye defects arise from Pax6 mutations in many different organisms. 
C) Pax6 DNA and protein sequences are highly conserved in a wide range of organisms. 
D) Pax6 protein is so central to eye development that after transferring the mouse Pax6 to the fruit fly, the fly produces eyes similar to that of a mouse. 
E) The Pax6 gene evolved early and is shared among a wide range of animals, despite the structural diversity in their final adult eyes. 
A) The light-sensitive molecule for all light-sensing cells is the same, a derivative of vitamin A complexed with a protein called opsin. 
B) Eye defects arise from Pax6 mutations in many different organisms. 
C) Pax6 DNA and protein sequences are highly conserved in a wide range of organisms. 
D) Pax6 protein is so central to eye development that after transferring the mouse Pax6 to the fruit fly, the fly produces eyes similar to that of a mouse. 
E) The Pax6 gene evolved early and is shared among a wide range of animals, despite the structural diversity in their final adult eyes.

Question 11

A researcher isolates stem cells from a developing embryo and finds that they are able to differentiate only into liver cells or pancreatic cells. The isolated stem cells are:

Accepted Answer

A) pluripotent. 
B) omnipotent. 
C) omniscient. 
D) multipotent. 
E) impotent. 
A) pluripotent. 
B) omnipotent. 
C) omniscient. 
D) multipotent. 
E) impotent.

Question 12

Cells of the mesoderm are multipotent because they can:

Accepted Answer

A) give rise to any cell type in the embryo. 
B) give rise to any cell type of mesodermal origin. 
C) give rise to any cell type of any of the three germ layers. 
D) become induced pluripotent stem cells. 
E) None of the answer options is correct. 
A) give rise to any cell type in the embryo. 
B) give rise to any cell type of mesodermal origin. 
C) give rise to any cell type of any of the three germ layers. 
D) become induced pluripotent stem cells. 
E) None of the answer options is correct.

Question 13

Imagine that a doctor is presented with a patient that lacks irises. What could be said of this patient?

Accepted Answer

A) This patient likely carries a loss-of-function mutation. 
B) This patient could be diagnosed as having aniridia. 
C) This patient likely carries a mutation in Pax6. 
D) This patient may carry mutations in genes downstream of Pax6. 
E) All of these choices are correct. 
A) This patient likely carries a loss-of-function mutation. 
B) This patient could be diagnosed as having aniridia. 
C) This patient likely carries a mutation in Pax6. 
D) This patient may carry mutations in genes downstream of Pax6. 
E) All of these choices are correct.

Question 14

In a normal Drosophila embryo, a gap gene called Krüppel is expressed in the anterior end because it is activated by Hunchback protein, and this region contains a high level of Hunchback.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following statements is TRUE regarding AP2, AP3, PI, and AG?

Accepted Answer

A) These proteins interact with cis-regulatory elements of specific genes. 
B) None of these proteins bind with one another to form heterodimers. 
C) These are the only transcription factors involved in plant flower development. 
D) All of these proteins act independently-they are not involved in any aspect of combinatorial control. 
A) These proteins interact with cis-regulatory elements of specific genes. 
B) None of these proteins bind with one another to form heterodimers. 
C) These are the only transcription factors involved in plant flower development. 
D) All of these proteins act independently-they are not involved in any aspect of combinatorial control.

Question 16

Homeotic genes encode transcription factor proteins that bind DNA. The DNA-binding domain of homeotic proteins is called a _____, and is a highly conserved region in many homeotic proteins.

Accepted Answer

A) homeodomain 
B) paired domain 
C) transactivation domain 
D) regulatory domain 
E) half domain 
A) homeodomain 
B) paired domain 
C) transactivation domain 
D) regulatory domain 
E) half domain

Question 17

Imagine that a human embryo carries a mutation in the gene encoding the Notch receptor. What will this mutation affect in the embryo?

Accepted Answer

A) bone development 
B) heart development 
C) nervous system development 
D) pancreas development 
E) All of these choices are correct. 
A) bone development 
B) heart development 
C) nervous system development 
D) pancreas development 
E) All of these choices are correct.

Question 18

Transcription factors like Pax6 interact with their target genes by binding short sequences adjacent to the 5' end of a gene sequence called _____ elements.

Accepted Answer

A) gain-of-function 
B) loss-of-function 
C) cis-regulatory 
D) downstream 
E) combinatorial 
A) gain-of-function 
B) loss-of-function 
C) cis-regulatory 
D) downstream 
E) combinatorial

Question 19

A researcher isolates stem cells from a developing embryo and finds that they are able to differentiate only into liver cells or pancreatic cells. The isolated stem cells are likely from the:

Accepted Answer

A) morula. 
B) gastrula. 
C) ectoderm. 
D) mesoderm. 
E) endoderm. 
A) morula. 
B) gastrula. 
C) ectoderm. 
D) mesoderm. 
E) endoderm.

Question 20

A signaling molecule that binds a membrane protein is called a:

Accepted Answer

A) receptor. 
B) transcription factor. 
C) ligand. 
D) protein cascade. 
A) receptor. 
B) transcription factor. 
C) ligand. 
D) protein cascade.

Exam 20: Genes and Development

In John Gurdon's nuclear-transfer experiments, do you think he would have had more or less success if he had taken cells from a blastula? From an adult frog?

Cells differentiate through:

When pair-rule genes and segment-polarity genes are mutated, larvae display disturbances in segmentation patterns.

Why has the development of iPS cells been viewed as a major breakthrough in the development of stem cell therapies?

In human development, cell rearrangement within the ball of cells leads to a hollow sphere with a "mound" of cells at one pole. This group of cells is called the:

Review Figure 20.19. Which floral organ develops from whorl 3 in Arabidopsis?

Which one of the following statements about homeotic, or Hox, genes is NOT correct?

In mammals, Hox genes:

Examine the figure and statements below. Which of the statements is INCORRECT?

Which of the following statements about the development and function of the visual system in animals is INCORRECT?

A researcher isolates stem cells from a developing embryo and finds that they are able to differentiate only into liver cells or pancreatic cells. The isolated stem cells are:

Cells of the mesoderm are multipotent because they can:

Imagine that a doctor is presented with a patient that lacks irises. What could be said of this patient?

In a normal Drosophila embryo, a gap gene called Krüppel is expressed in the anterior end because it is activated by Hunchback protein, and this region contains a high level of Hunchback.

Which of the following statements is TRUE regarding AP2, AP3, PI, and AG?

Homeotic genes encode transcription factor proteins that bind DNA. The DNA-binding domain of homeotic proteins is called a _____, and is a highly conserved region in many homeotic proteins.

Imagine that a human embryo carries a mutation in the gene encoding the Notch receptor. What will this mutation affect in the embryo?

Transcription factors like Pax6 interact with their target genes by binding short sequences adjacent to the 5' end of a gene sequence called _____ elements.

A researcher isolates stem cells from a developing embryo and finds that they are able to differentiate only into liver cells or pancreatic cells. The isolated stem cells are likely from the:

A signaling molecule that binds a membrane protein is called a:

Life: Chemical, Cellular, and Evolutionary Foundations

The Molecules of Life

Nucleic Acids and Transcription

Translation and Protein Structure

Organizing Principles: Lipids, Membranes, and Cell Compartments

Making Life Work: Capturing and Using Energy

Cellular Respiration: Harvesting Energy From Carbohydrates and Other Fuel Molecules

Photosynthesis: Using Sunlight to Build Carbohydrates

Cell Signaling

Cell and Tissue Architecture: Cytoskeleton, Cell Junctions, and Extracellular Matrix

Cell Division: Variations, Regulation, and Cancer

Dna Replication and Manipulation

Genomes

Mutation and Dna Repair

Genetic Variation

Mendelian Inheritance

Inheritance of Sex Chromosomes, Linked Genes, and Organelles

The Genetic and Environmental Basis of Complex Traits

Genetic and Epigenetic Regulation

Evolution: How Genotypes and Phenotypes Change Over Time

Species and Speciation

Evolutionary Patterns: Phylogeny and Fossils

Human Origins and Evolution

Cycling Carbon

Bacteria and Archaea

Eukaryotic Cells: Origins and Diversity

Being Multicellular

Plant Structure and Function: Moving Photosynthesis Onto Land

Plant Reproduction: Finding Mates and Dispersing Young

Plant Growth and Development

Plant Defense: Keeping the World Green

Plant Diversity

Fungi: Structure, Function, and Diversity

Animal Nervous Systems

Animal Sensory Systems and Brain Function

Animal Movement: Muscles and Skeletons

Animal Endocrine Systems

Animal Cardiovascular and Respiratory Systems

Animal Metabolism, Nutrition, and Digestion

Animal Renal Systems: Water and Waste

Animal Reproduction and Development

Animal Immune Systems

Animal Diversity

Animal Behavior

Population Ecology

Species Interactions, Communities, and Ecosystems

Biomes and Global Ecology

The Anthropocene: Humans As a Planetary Force

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