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Wolpert et al, Principles of Development 6e Test bank Type: multiple choice question Title: Chapter 01 - Question 01 01) Which of these terms refers to the “generation of form?” a. Developmental biology Feedback: No, developmental biology is the field of biology focused on understanding how animals and plants develop. Page reference: 2 b. Embryogenesis Feedback: No, embryogenesis is the development of an embryo from a fertilized egg. Page reference: 2 *c. Morphogenesis Feedback: Yes, morphogenesis is the development of form. The meaning comes from the words “morph” (form) and “genesis” (generation of). Page reference: 2 d. Embryology Feedback: No, embryology is an outdated term to describe the study of developmental biology. Modern developmental biologists appreciate that development of an organism continues after embryogenesis. Page reference: 3 Type: multiple choice question Title: Chapter 01 - Question 02 02) Which of these is true of meiosis? *a. Germ cells are formed through this process. Feedback: Yes, this is true. Germ cells, sperm and egg, are formed when a diploid cell undergoes meiosis to give rise to four cells containing half the number of chromosomes (haploid). Page reference: 6 b. A zygote is formed through this process. Feedback: No, this is not true. A zygote is formed when fusion of a haploid egg nucleus with a haploid sperm nucleus takes place. Page reference: 5 c. This process is carried out during cleavage stage. Feedback: No, this is not true. Cleavage stage is when a single-celled zygote undergoes rapid mitotic cell divisions. Page reference: 14 d. Daughter somatic cells are formed containing the same number of chromosomes as the parental cell. Feedback: No, this is not true. Mitosis is the type of cell division somatic cells use to keep the number of chromosomes constant from parental cell to daughter cells. Page reference: 5 Type: multiple choice question Title: Chapter 01 - Question 03 03) What is the key hypothesis of a mosaic model for developmental fate regulation? a. Normal development occurs even if cells are removed. Feedback: No, if normal development proceeds even after cell removal this highlights an embryo’s ability to regulate for this cell loss. This is the opposite of mosaic development where cytoplasmic determinants are specific to a subset of embryonic cells. Page reference: 24 b. Zygotic proteins and RNAs are equally distributed to daughter cells Feedback: No, zygotic cytoplasmic determinants are expected to be unequally distributed among daughter cells during cleavage events. This is how subpopulations of embryonic cells would establish different characteristics within the context of a mosaic model. Page reference: 24

Wolpert et al, Principles of Development 6e Test bank *c. Patterns of cell division control embryonic cell fate. Feedback: Yes, cytoplasmic determinants within the zygote are distributed unequally within daughter cells during cleavage stage. Each cell’s determinants control the future fate of that cell. Page reference: 24 d. Cells within an early embryo communicate with each other. Feedback: No, cell-cell communication is a key expectation of cells within an embryo capable of regulating for cell loss. It is understood that communication is necessary for sensing cell loss. Page reference: 24 Type: multiple choice question Title: Chapter 01 - Question 04 04) The influence of one cell over another neighbouring cell’s development is called. a. Interaction Feedback: No, induction is where one cell, or tissue, directs the development of another neighbouring cell or tissue through cell-cell signalling. Page reference: 8 b. Communication Feedback: No, induction is where one cell, or tissue, directs the development of another neighbouring cell or tissue through cell-cell signalling. Page reference: 8 c. Organization Feedback: No, induction is where one cell, or tissue, directs the development of another neighbouring cell or tissue through cell-cell signalling. Page reference: 8 *d. Induction Feedback: Yes, induction is where one cell, or tissue, directs the development of another neighbouring cell or tissue through cell-cell signalling. Page reference: 8 Type: multiple choice question Title: Chapter 01 - Question 05 05) Which of the options given is not true of the Spemann-Mangold organizer experiment? a. The transplanted tissue is the dorsal lip of the blastopore. Feedback: No, this is true. The transplanted tissue is the dorsal lip of the blastopore from an unpigmented embryo. Page reference: 8 b. A secondary body axis developed, containing neural tube and somites. Feedback: No, this is true. The dorsal blastopore lip transplantation into the ventral surface of another embryo induced a secondary axis. Page reference: 8 c. The transplanted tissue resides near the region where gastrulation begins. Feedback: No, this is true. The blastopore is the site where gastrulation begins in the newt. The dorsal lip of the slit-like invagination is the organizer tissue. Page reference: 8 *d. Every induced tissue was pigmented. Feedback: No, this is not true. Tissues within the induced secondary axis contained cells of graft (unpigmented) and host (pigmented) origin. This suggests that cells within the graft tissue send inductive signals to the host tissue. Page reference: 8 Type: multiple choice question Title: Chapter 01 - Question 06 06) Which developmental process establishes a coordinate system whereby cells “know” their location within an embryo?

Wolpert et al, Principles of Development 6e Test bank a. Morphogenesis Feedback: No, morphogenesis is the generation of form through cell shape change and movements. Page reference: 16 b. Cell differentiation Feedback: No, differentiation is the process of cells becoming structurally and functionally different from each other, ending up as distinct specialized cell types. Page reference: 16 *c. Pattern formation Feedback: Yes, pattern formation involves the establishment of a body plan with defined main body axes. Cells with knowledge of their spatial position along the anterio-posterior, dorsoventral, and right-left axes can develop accordingly. Page reference: 14 d. Growth Feedback: No, growth is the increase in size. Growth can occur through increases in cell number or size. Page reference: 16 Type: multiple choice question Title: Chapter 01 - Question 07 07) Pancreatic and muscle cells are specialized to perform distinct functions but contain the exact same set of genetic instructions. Which of the options given does not represent a mechanism to accomplish this? *a. Differentiated cells lose genes that are unrelated to their function. Feedback: Yes, this is not a proper mechanism. Animal cloning experiments, such as the one performed by John Gurdon, suggest that adult differentiated cells contain the same set of genetic instructions as cells within the early embryo. Page reference: 19 b. Differentiated cells contain distinct gene-regulatory proteins Feedback: No, this is a proper mechanism. Gene regulatory proteins, in different combinations, determine the list of genes that are expressed in specific cell types within the organism. Page reference: 19 c. Differentiated cells use distinct gene control regions. Feedback: No, this is a proper mechanism. Gene regulatory proteins, in different combinations, bind to and activate or repress specific DNA control regions. This creates a bank of expressed cell-specific genes that dictates a cell’s function. Page reference: 20 d. Differentiated cells undergo specific types of post-translational protein modification. Feedback: No, this is a proper mechanism. Even if a gene is expressed and the protein produced, cells can modify the same protein differently between cell types. This can lead to differences in cellular behaviour. Page reference: 18 Type: multiple choice question Title: Chapter 01 - Question 08 08) What do we call a group of cells that differentiates according to its normal fate after it has been isolated from the embryo and cultured in a neutral environment? a. Determined Feedback: No, determination is assessed by transplanting cells from their normal embryonic region to an ectopic embryonic region and observing their fate. Page reference: 22 b. Chimeric Feedback: No, a chimera is a mosaic of cells with different genetic make-up. Page reference: 24

Wolpert et al, Principles of Development 6e Test bank *c. Specified Feedback: Yes, an isolated cell is said to be specified if its final differentiated state in isolation mimics its expected embryonic fate. Page reference: 22 d. Competent Feedback: No, competence is a term used to describe a cell’s ability to receive and respond to an inductive signal. Page reference: 25 Type: multiple choice question Title: Chapter 01 - Question 09 09) Which of the options given is not true of the French flag mechanism of pattern formation? *a. Differing concentrations of a teratogen provide positional values. Feedback: Yes, this is not true. Differing concentrations of morphogens provide positional values by diffusing away from a source. Teratogens are chemicals that cause abnormal development. Page reference: 29 b. Cells develop according to threshold concentrations of a molecule. Feedback: No, this is true. Cells that receive a morphogen above a particular concentration develop differently than nearby cells that receive a morphogen below that concentration threshold. Page reference: 29 c. Experiments using amphibian and insect limbs were among the first to lend support to this model. Feedback: No, this is true. Regenerating amphibian and insect limbs, in which they regenerated missing tissues, played a key part in the establishment of this model. It is understood that regenerating tissues must acknowledge their position in order to know what is missing and to replace it in the correct spatial position. Page reference: 29 d. The model gets its name from the three colors of the French flag (blue, white, red). Feedback: No, this is true. The three domains of color within the flag represent three regions of cells receiving differing concentration thresholds of a morphogen along a line. Cells within each domain establish distinct genetic programs that define their fate. Page reference: 27 Type: multiple choice question Title: Chapter 01 - Question 10 10) A human zygote, which has the potential to give rise to a complete new human, is often described as what type of cell? a. Unipotent Feedback: No, a unipotent cell can only give rise to one type of cell. Page reference: 31 b. Multipotent Feedback: No, a multipotent cell has the potential of differentiating into many, but not all cell types. Its fate is far more restricted than a pluripotent cell. Page reference: 31 *c. Totipotent Feedback: Yes, a human zygote is the only cell known to have the potential of giving rise to a complete new human. We refer to the zygote as totipotent. Page reference: 32 d. Pluripotent Feedback: No, pluripotent cells have the potential to give rise to all the cells in the body but haven’t been shown to be able to give rise to a complete new human on their own. Page reference: 31

Wolpert et al, Principles of Development 6e Test bank

Wolpert et al, Principles of Development 6e Test bank Type: MC question Title: Chapter 02 - Question 01 01) What is the result of the first 12 nuclear divisions of a Drosophila embryo where roughly 6,000 nuclei share a single cytoplasm? a. Micropyle @ No, a micropyle is the structure through which sperm enters the anterior end of the egg. Page reference: 38 b. Cellular blastoderm @ No, the cellular blastoderm occurs only after membranes form around peripheral nuclei. A single cytoplasm is no longer shared at this point as cellularization has taken place. Page reference: 39 *c. Syncytium @ Yes, the first twelve nuclear divisions occur without cytokinesis to give rise to a single cytoplasm containing roughly 6,000 nuclei. This single cell is referred to as a syncytium. Page reference: 38 d. Pole cell @ No, pole cells are a small population of individual cells that will become germ cells from which the gametes will be derived. Page reference: 40 Type: MC question Title: Chapter 02 - Question 02 02) Which of the options given is not true of the Drosophila mesoderm? a. It gives rise to muscle and connective tissue. @ No, this is true. Muscle and connective tissue are important mesoderm-derived tissues in vertebrate and invertebrate embryos. Page reference: 40 b. Gastrulation internalizes the mesoderm. @ No, this is true. Cellular rearrangements during gastrulation forces blastoderm cells to the interior of the embryo. Page reference: 40 c. The mesoderm is a primary germ layer. @ No, this is true. The mesoderm is a primary germ layer, along with endoderm and ectoderm. Page reference: 40 *d. The dorsal surface of the blastoderm gives rise to mesoderm. @ Yes, this is not true. Gastrulation forces ventral blastoderm cells into the interior of the embryo, thus forming the mesoderm. Page reference: 40 Type: MC question Title: Chapter 02 - Question 03 03) Which term is not associated with a Drosophila larva? a. Instar @ No, an instar is a larval stage with successive periods of growth, molting, and shedding. Page reference: 41 *b. Metamorphosis @ Yes, metamorphosis is a process within a pupa where a major transformation of the adult form takes place. The pupal stage occurs after the larval stage. Page reference: 41 c. Denticles @ No, denticles are belts of small tooth-like outgrowths from the epidermal cuticle. Page reference: 41 d. Imaginal discs

Wolpert et al, Principles of Development 6e Test bank @ No, imaginal discs are small sheets of epidermal cells from which adult tissues, like legs and wings, are derived. Imaginal discs undergo cell proliferation during larval stages. Page reference: 41 Type: MC question Title: Chapter 02 - Question 04 04) What is the maternal anterior morphogen that controls head and thorax development? *a. Bicoid @ Yes, bicoid mRNA translation at fertilization gives rise to an anterior to posterior gradient that is required for development of anterior structures. Page reference: 47 b. Nanos @ No, nanos mRNA translation at fertilization gives rise to a posterior to anterior gradient that is required for development of posterior structures. Page reference: 47 c. Caudal @ No, caudal mRNA translation at fertilization gives rise to a posterior to anterior gradient that is required for development of posterior structures. Page reference: 50 d. Torso @ No, Torso is required for development of the extreme ends (acron and telson) of the embryo. Page reference: 51 Type: MC question Title: Chapter 02 - Question 05 05) Which of the options given is not true of the Drosophila Dorsal protein? a. Control regions of target genes differ in their affinity for the Dorsal protein. @ No, this is true. Dorsal protein can bind with different affinity to control regions of its target genes. This characteristic adds to the complexity of target gene expression across the dorsoventral axis of the Drosophila embryo. Page reference: 62 b. The dorsal region of the Drosophila embryo expresses genes that are repressed by the Dorsal protein. @ No, this is true. Dorsal protein can act as repressor and activator of gene expression. Because Dorsal protein is high in the ventral region, repressed genes show expression within dorsal cells of the Drosophila embryo. Page reference: 62 c. The gradient of Dorsal protein divides the Drosophila embryo up into at least four well-defined domains. @ No, this is true. A French flag model can be invoked to describe the patterning of the dorsoventral axis within the Drosophila embryo. Page reference: 62 *d. Dorsal protein levels are higher within the dorsal region of the Drosophila embryo. @ Yes, this is not true. Dorsal protein levels are higher within the ventral region of the Drosophila embryo. Page reference: 62 Type: MC question Title: Chapter 02 - Question 06 06) What class of patterning genes are expressed within seven transverse stripes in the Drosophila embryo? *a. Pair-rule genes @ Yes, pair-rule genes are expressed in seven transverse stripes within alternating parasegments.

Wolpert et al, Principles of Development 6e Test bank Page reference: 72 b. Segmentation genes @ No, segmentation genes are expressed in 14 transverse stripes. Page reference: 76 c. Gap genes @ No, gap genes are expressed in broad regions. Page reference: 66 d. Hox genes @ No, Hox genes are expressed in broad regions along the anterio-posterior axis. Page reference: 84 Type: MC question Title: Chapter 02 - Question 07 07) What class of patterning genes encodes members of intercellular signaling pathways? a. Pair-rule genes @ No, pair-rule genes encode transcription factors that function within a syncytium prior to cellularization. Page reference: 72 *b. Segmentation genes @ Yes, segmentation genes function after the blastoderm becomes cellularized. Therefore, signaling proteins and their receptors are necessary to define parasegment boundaries. Page reference: 78 c. Gap genes @ No, gap genes encode transcription factors that function within a syncytium prior to cellularization. Page reference: 66 d. Hox genes @ No, all Hox genes encode transcription factors that define the identity of embryonic segments. Page reference: 85 Type: MC question Title: Chapter 02 - Question 08 08) Which of these segmentation genes is a transcription factor that defines parasegment boundaries? a. Frizzled @ No, Frizzled is the receptor for the Wingless signaling protein. Page reference: 78 b. Hedgehog @ No, Hedgehog is an intercellular signaling protein. Page reference: 78 c. Patched @ No, Patched is the receptor for the Hedgehog signaling protein. Page reference: 78 *d. Engrailed @ Yes, Engrailed is a transcription factor that limits the pattern of Hedgehog and Wingless signaling pathways to define parasegment boundaries. Page reference: 78 Type: MC question Title: Chapter 02 - Question 09 09) What is the term that describes the relation between the order of the Hox genes along the chromosome and the order of their expression along the antero-posterior axis? a. Homeosis @ No, homeosis is the transformation of a whole segment into another related one.