Question 1

Undifferentiated cells that continue to proliferate throughout an individual's life are referred to by what terms in plants and animals respectively?

Accepted Answer

A) stem cells and stem cells 
B) meristems and meristems 
C) stem cells and meristems 
D) meristems and stem cells 
A) stem cells and stem cells 
B) meristems and meristems 
C) stem cells and meristems 
D) meristems and stem cells D

Question 2

Cellular differentiation results from

Accepted Answer

A) changes in the genetic makeup of cells. 
B) differential gene expression. 
C) mutations in DNA. 
A) changes in the genetic makeup of cells. 
B) differential gene expression. 
C) mutations in DNA. B

Question 3

Gene expression in developing organisms is regulated on several different levels.In many developing animals,regulation of gene expression is influenced by the action of Hox genes.Which of the following regulatory elements are produced by many Hox genes?

Accepted Answer

A) transcriptional factors 
B) cell surface molecules for cell-cell interactions 
C) signals from maternal cytoplasm,such as bicoid 
D) mRNA processing factors 
A) transcriptional factors 
B) cell surface molecules for cell-cell interactions 
C) signals from maternal cytoplasm,such as bicoid 
D) mRNA processing factors A

Question 4

Modern cloning techniques have demonstrated that the vast majority of differentiated cells are genetically equivalent to developing cells in the embryo.What is an exception to this finding?

Accepted Answer

A) Nerve cells are often limited in their mitotic activity. 
B) In the immune system,sequences of DNA may rearrange to permit response to new pathogens. 
C) In the brain,DNA sequences may change with learned behavior. 
D) The lining of the digestive system is frequently replaced.Some of these cells may show repeats of certain DNA sequences. 
A) Nerve cells are often limited in their mitotic activity. 
B) In the immune system,sequences of DNA may rearrange to permit response to new pathogens. 
C) In the brain,DNA sequences may change with learned behavior. 
D) The lining of the digestive system is frequently replaced.Some of these cells may show repeats of certain DNA sequences.

Question 5

One form of programmed cell death is apoptosis.In which developmental situation would you predict apoptosis would NOT play a major role?

Accepted Answer

A) growth of nerves and blood vessels into a body segment 
B) sculpting of digits in the developing hindlimb 
C) growth of the atrial septum in the four-chambered mammalian heart 
D) disappearance of the embryonic tail in developing humans 
A) growth of nerves and blood vessels into a body segment 
B) sculpting of digits in the developing hindlimb 
C) growth of the atrial septum in the four-chambered mammalian heart 
D) disappearance of the embryonic tail in developing humans

Question 6

Suppose the protein specified by bicoid were injected into Drosophila embryos,so that a high concentration was present everywhere in the embryo.What might be the result of such an experiment?

Accepted Answer

A) The embryos would grow larger than normal. 
B) The embryos would show no development of posterior regions. 
C) The embryos would show no development of anterior regions. 
D) The embryos would halt their development. 
A) The embryos would grow larger than normal. 
B) The embryos would show no development of posterior regions. 
C) The embryos would show no development of anterior regions. 
D) The embryos would halt their development.

Question 7

Suppose there was a mutation in the segment-polarity genes of Drosophila.What do you suppose might be the outcome?

Accepted Answer

A) Several segments of the embryo will be missing. 
B) Every other segment of the embryo will be missing. 
C) Legs will appear in the place of antennae. 
D) Antennae will appear in a different part of their usual segment. 
A) Several segments of the embryo will be missing. 
B) Every other segment of the embryo will be missing. 
C) Legs will appear in the place of antennae. 
D) Antennae will appear in a different part of their usual segment.

Question 8

Cloning of plants from cuttings demonstrates that

Accepted Answer

A) genetic information is lost during plant development. 
B) differentiated cells may contain embryonic mRNAs. 
C) plants can reverse the differentiation process. 
D) genetic information is retained in mature plant cells. 
A) genetic information is lost during plant development. 
B) differentiated cells may contain embryonic mRNAs. 
C) plants can reverse the differentiation process. 
D) genetic information is retained in mature plant cells.

Question 9

In combination,what do the products of gap genes,pair-rule genes,and segmentation polarity genes of fruit flies do?

Accepted Answer

A) They trigger the reorganization of the larval body into an adult body. 
B) They define the segmented body plan of the embryo. 
C) They set up the back-to-belly axis of the larval body. 
D) They direct cell movements during differentiation. 
A) They trigger the reorganization of the larval body into an adult body. 
B) They define the segmented body plan of the embryo. 
C) They set up the back-to-belly axis of the larval body. 
D) They direct cell movements during differentiation.

Question 10

Which of the following would constitute evidence that differentiated cells retain all the genes of developing cells?

Accepted Answer

A) Developing cells have many mRNA transcripts that can hybridize with DNA from mature cells. 
B) Differentiated cells generally synthesize a specific group of proteins. 
C) Nuclei from mature cells can direct the development of an entire individual. 
D) Differentiated cells lose their polarity if removed from the organism. 
A) Developing cells have many mRNA transcripts that can hybridize with DNA from mature cells. 
B) Differentiated cells generally synthesize a specific group of proteins. 
C) Nuclei from mature cells can direct the development of an entire individual. 
D) Differentiated cells lose their polarity if removed from the organism.

Question 11

Which of the following terms refers to a cell that is capable of dividing and developing into a limited number of cell types in a multicellular organism?

Accepted Answer

A) multipotent 
B) pluripotent 
C) totipotent 
A) multipotent 
B) pluripotent 
C) totipotent

Question 12

What does the term "genetic equivalence" refer to?

Accepted Answer

A) Plant cells can differentiate into animal cells and vice versa. 
B) Differentiated cells of a plant contain the same genes as other cells in the same plant. 
C) Differentiated animal cells can share gene products with each other,resulting in a balance of products among the cells. 
D) During development,sending and receiving of signals via cell-cell interactions makes the cells involved more equal. 
A) Plant cells can differentiate into animal cells and vice versa. 
B) Differentiated cells of a plant contain the same genes as other cells in the same plant. 
C) Differentiated animal cells can share gene products with each other,resulting in a balance of products among the cells. 
D) During development,sending and receiving of signals via cell-cell interactions makes the cells involved more equal.

Question 13

Animal species exhibit an enormous diversity of genetic information contained in nuclear DNA.This may be reflected in very different genome sizes.One might predict that animals with more complex structures might show greater numbers of different types of mRNAs during development.Scientists investigating this possibility were surprised to find that similar numbers of genes were transcribed at a particular time in development among species whose genomes differed greatly in size.How can this result be interpreted?

Accepted Answer

A) Some species retain large amounts of DNA that are never used. 
B) The number of genes transcribed at any one time is tightly regulated and independent of genome size. 
C) Genome size has nothing to do with the physical complexity of the species. 
D) Nuclear DNA complexity is unrelated to the complexity of mRNAs transcribed during development. 
A) Some species retain large amounts of DNA that are never used. 
B) The number of genes transcribed at any one time is tightly regulated and independent of genome size. 
C) Genome size has nothing to do with the physical complexity of the species. 
D) Nuclear DNA complexity is unrelated to the complexity of mRNAs transcribed during development.

Question 14

The protein of the bicoid gene in Drosophila determines

Accepted Answer

A) the anterior-posterior axis of the embryo. 
B) the ventral-lateral axis of the embryo. 
C) the medial-lateral axis of the embryo. 
D) the number of segments in the embryo. 
A) the anterior-posterior axis of the embryo. 
B) the ventral-lateral axis of the embryo. 
C) the medial-lateral axis of the embryo. 
D) the number of segments in the embryo.

Question 15

Cells in a developing embryo are subject to a number of regulatory pressures.Which of the following is NOT a source of regulatory signals in animal development?

Accepted Answer

A) oocyte cytoplasm 
B) sperm nucleus 
C) nearby cells 
D) extracellular matrix 
A) oocyte cytoplasm 
B) sperm nucleus 
C) nearby cells 
D) extracellular matrix

Question 16

What types of changes in the regulation of development can lead to evolutionarily significant morphological changes?

Accepted Answer

A) Changes in when developmental genes are expressed. 
B) Changes in where developmental genes are expressed. 
C) Changes in development are not evolutionarily significant. 
D) Both A and B are evolutionarily significant. 
A) Changes in when developmental genes are expressed. 
B) Changes in where developmental genes are expressed. 
C) Changes in development are not evolutionarily significant. 
D) Both A and B are evolutionarily significant.

Question 17

Cellular differentiation is usually produced by

Accepted Answer

A) differences in gene expression. 
B) differences in DNA sequences. 
C) differences in gene copy numbers. 
D) morphogenesis. 
A) differences in gene expression. 
B) differences in DNA sequences. 
C) differences in gene copy numbers. 
D) morphogenesis.

Question 18

In snake populations,rare individuals are found that have well-developed hind limbs.They are normal in all other respects.This finding shows that

Accepted Answer

A) some snakes have mutations in Hox genes that permit development of limbs. 
B) snakes retain the genes for hindlimb pattern formation,even though the genes are usually not activated during development. 
C) some snakes may lack the regulatory inhibitors necessary for normal limbless development. 
D) all of the above might explain this rare condition. 
A) some snakes have mutations in Hox genes that permit development of limbs. 
B) snakes retain the genes for hindlimb pattern formation,even though the genes are usually not activated during development. 
C) some snakes may lack the regulatory inhibitors necessary for normal limbless development. 
D) all of the above might explain this rare condition.

Question 19

What is common to gap genes,segment-polarity genes,and homeotic genes?

Accepted Answer

A) They act independently of one another. 
B) They code for transcription regulatory factors. 
C) They can be activated at any time during development. 
D) They are unique to Drosophila embryos. 
A) They act independently of one another. 
B) They code for transcription regulatory factors. 
C) They can be activated at any time during development. 
D) They are unique to Drosophila embryos.

Question 20

During development,what a cell differentiates into depends in part on its location along three body axes.Which axis runs towards the organism's head?

Accepted Answer

A) dorsal 
B) anterior 
C) posterior 
D) ventral 
A) dorsal 
B) anterior 
C) posterior 
D) ventral

Exam 21: Principles of Development

Undifferentiated cells that continue to proliferate throughout an individual's life are referred to by what terms in plants and animals respectively?

Cellular differentiation results from

Gene expression in developing organisms is regulated on several different levels.In many developing animals,regulation of gene expression is influenced by the action of Hox genes.Which of the following regulatory elements are produced by many Hox genes?

Modern cloning techniques have demonstrated that the vast majority of differentiated cells are genetically equivalent to developing cells in the embryo.What is an exception to this finding?

One form of programmed cell death is apoptosis.In which developmental situation would you predict apoptosis would NOT play a major role?

Suppose the protein specified by bicoid were injected into Drosophila embryos,so that a high concentration was present everywhere in the embryo.What might be the result of such an experiment?

Suppose there was a mutation in the segment-polarity genes of Drosophila.What do you suppose might be the outcome?

Cloning of plants from cuttings demonstrates that

In combination,what do the products of gap genes,pair-rule genes,and segmentation polarity genes of fruit flies do?

Which of the following would constitute evidence that differentiated cells retain all the genes of developing cells?

Which of the following terms refers to a cell that is capable of dividing and developing into a limited number of cell types in a multicellular organism?

What does the term "genetic equivalence" refer to?

The protein of the bicoid gene in Drosophila determines

Cells in a developing embryo are subject to a number of regulatory pressures.Which of the following is NOT a source of regulatory signals in animal development?

What types of changes in the regulation of development can lead to evolutionarily significant morphological changes?

Cellular differentiation is usually produced by

In snake populations,rare individuals are found that have well-developed hind limbs.They are normal in all other respects.This finding shows that

What is common to gap genes,segment-polarity genes,and homeotic genes?

During development,what a cell differentiates into depends in part on its location along three body axes.Which axis runs towards the organism's head?

Biology and the Tree of Life

Water and Carbon: the Chemical Basis of Life

Protein Structure and Function

Nucleic Acids and the Rna World

An Introduction to Carbohydrates

Lipids, membranes, and the First Cells

Inside the Cell

Cell-Cell Interactions

Cellular Respiration and Fermentation

Photosynthesis

The Cell Cycle

Meiosis

Mendel and the Gene

Dna and the Gene: Synthesis and Repair

How Genes Work

Transcription, RNA Processing, and Translation

Control of Gene Expression in Bacteria

Control of Gene Expression in Eukaryotes

Analyzing and Engineering Genes

Genomics

An Introduction to Animal Development

An Introduction to Plant Development

Evolution by Natural Selection

Evolutionary Processes

Speciation

Phylogenies and the History of Life

Bacteria and Archaea

Protists

Green Algae and Land Plants

Fungi

An Introduction to Animals

Protostome Animals

Deuterostome Animals

Viruses

Plant Form and Function

Water and Sugar Transport in Plants

Plant Nutrition

Plant Sensory Systems, signals, and Responses

Plant Reproduction

Animal Form and Function

Water and Electrolyte Balance in Animals

Animal Nutrition

Gas Exchange and Circulation

Electrical Signals in Animals

Animal Sensory Systems and Movement

Chemical Signals in Animals

Animal Reproduction

The Immune System in Animals

An Introduction to Ecology

Behavioural Ecology

Population Ecology

Community Ecology

Ecosystems

Biodiversity and Conservation Biology

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