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Which of the following characteristics of vaccines are required in order for them to be effective in immunization? (Select all that apply.)


A) They must contain the entire pathogen.
B) They must present antigenic surfaces recognized by immunoglobulin molecules.
C) They must stimulate lymphocyte activity.
D) They must stimulate the production of large quantities of plasma cells.
E) They must stimulate the production of memory cells.

F) A) and E)
G) All of the above

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What is apoptosis?


A) autophagy
B) a process that generates the anterior-posterior axis
C) antibody production
D) genetic maternal effect
E) programmed cell death

F) A) and C)
G) A) and B)

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What is apoptosis? Describe the important roles that apoptosis plays during development of an organism. Provide specific evidence that apoptosis is important to normal development.

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Apoptosis is a process of programmed cel...

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Which of the following statements about homeotic genes is INCORRECT?


A) Homeotic genes were first identified in invertebrates, but their homologs were found in almost all organisms.
B) All homeotic genes contain consensus sequences that result in a specific DNA-binding motif.
C) In vertebrates, homeotic genes are organized into two distinct clusters.
D) All homeotic genes encode transcription factors that direct further gene expression.
E) Homeotic genes exhibit a relationship between their order on the chromosome and the timing of their expression.

F) A) and D)
G) B) and C)

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The following diagram describes the genetic regulation of flower development in angiosperms. In each box, write the class of gene, and below write the flower structures determined by those gene(s). The following diagram describes the genetic regulation of flower development in angiosperms. In each box, write the class of gene, and below write the flower structures determined by those gene(s).

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Use the following to answer questions The diagram below illustrates the normal expression of three different groups of genes (A, B, and C) within four different whorls of a developing flower. Normally, whorl 1 produces sepals, whorl 2 produces petals, whorl 3 produces stamens, and whorl 4 produces carpels. Furthermore, expression of class A genes inhibits class C genes, and expression of class C inhibits class A. Use the following to answer questions  The diagram below illustrates the normal expression of three different groups of genes (A, B, and C)  within four different whorls of a developing flower. Normally, whorl 1 produces sepals, whorl 2 produces petals, whorl 3 produces stamens, and whorl 4 produces carpels. Furthermore, expression of class A genes inhibits class C genes, and expression of class C inhibits class A.   -What kind of mutation would produce sepals in all four whorls? A)  defective in A B)  defective in B C)  defective in C D)  defective in A and B E)  defective in B and C -What kind of mutation would produce sepals in all four whorls?


A) defective in A
B) defective in B
C) defective in C
D) defective in A and B
E) defective in B and C

F) A) and B)
G) A) and C)

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The Bicoid protein in fruit flies specifies anterior development. In the absence of Bicoid protein in an egg, the embryo will develop two tails. The bcd- mutation is recessive and exhibits a maternal effect. Which of the following CORRECTLY describes the embryos produced from a cross between a bcd+/ bcd- male and a bcd-/bcd- female?


A) All embryos will be normal.
B) All embryos will have two tails.
C) Three-fourths of the embryos will have two tails.
D) One-half of the embryos will have two tails.
E) One-fourth of the embryos will have two tails.

F) A) and E)
G) A) and C)

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The primary function of differentiated B lymphocytes within the vertebrate immune system is to produce:


A) cytotoxic chemicals.
B) hormones.
C) antibodies.
D) ROS.
E) complements.

F) All of the above
G) A) and B)

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During development, cells can respond to the presence of hormones and other signals with changes in gene expression that can bring about cell differentiation. In most cases, the differentiated state needs to be maintained through subsequent cell divisions and long after the inducing signal has disappeared. Describe a mechanism that can maintain the differentiated state after the inducing signal has disappeared.

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One mechanism that can maintain the diff...

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What have the cloning experiments in plants and animals confirmed with regard to developmental processes?

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Cloning experiments in plants and animal...

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Which specific group of genes specifies the identities of individual body segments?


A) segmentation genes
B) gap genes
C) homeotic genes
D) pair-rule genes
E) segment-polarity genes

F) All of the above
G) B) and E)

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C

Which of the following statements about Hox genes is INCORRECT?


A) All Hox genes found in organisms other than Drosophila have a conserved pattern of identical clustered arrangements.
B) When a vertebrate Hox gene is moved to a new location within the Hox gene complex, the timing of its expression is altered.
C) The Hox genes encode transcription factors that help to determine the identity of the body region.
D) They are usually organized as clusters and the order on the chromosome is important for their expression pattern.
E) The recent studies suggest the role of miRNA in controlling the expression of some Hox genes.

F) B) and C)
G) C) and E)

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A

Distinguish between the genetic mechanisms used to generate antibody diversity within a person's immune system and those used to generate MHC antigen diversity between different individuals.

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The genetic mechanisms used to generate ...

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Use the following to answer questions In the nematode worm C. elegans loss-of-function ced-3 mutations lead to more cells than normal due to a defect in apoptosis. Loss-of-function mutations in ced-9 cause embryonic lethality due to ectopic cell deaths. The phenotype of ced-9; ced-3 double mutants is the same as ced-3 single mutants; that is, there are more cells than normal due to a defect in apoptosis. Genes ced-3 and ced-9 are known to act in the same genetic pathway. -Which of the following pathways is consistent with the genetic data?


A) ced-3 \rightarrow ced-9
B) ced-9 \rightarrow ced -3
C) ced-3 Use the following to answer questions  In the nematode worm C. elegans loss-of-function ced-3 mutations lead to more cells than normal due to a defect in apoptosis. Loss-of-function mutations in ced-9 cause embryonic lethality due to ectopic cell deaths. The phenotype of ced-9; ced-3 double mutants is the same as ced-3 single mutants; that is, there are more cells than normal due to a defect in apoptosis. Genes ced-3 and ced-9 are known to act in the same genetic pathway. -Which of the following pathways is consistent with the genetic data? A)  ced-3  \rightarrow   ced-9 B)  ced-9  \rightarrow    ced -3 C)  ced-3  ced-9 D)  ced-9  ced-3 ced-9
D) ced-9 Use the following to answer questions  In the nematode worm C. elegans loss-of-function ced-3 mutations lead to more cells than normal due to a defect in apoptosis. Loss-of-function mutations in ced-9 cause embryonic lethality due to ectopic cell deaths. The phenotype of ced-9; ced-3 double mutants is the same as ced-3 single mutants; that is, there are more cells than normal due to a defect in apoptosis. Genes ced-3 and ced-9 are known to act in the same genetic pathway. -Which of the following pathways is consistent with the genetic data? A)  ced-3  \rightarrow   ced-9 B)  ced-9  \rightarrow    ced -3 C)  ced-3  ced-9 D)  ced-9  ced-3 ced-3

E) C) and D)
F) None of the above

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Use the following to answer questions The diagram below illustrates the normal expression of three different groups of genes (A, B, and C) within four different whorls of a developing flower. Normally, whorl 1 produces sepals, whorl 2 produces petals, whorl 3 produces stamens, and whorl 4 produces carpels. Furthermore, expression of class A genes inhibits class C genes, and expression of class C inhibits class A. Use the following to answer questions  The diagram below illustrates the normal expression of three different groups of genes (A, B, and C)  within four different whorls of a developing flower. Normally, whorl 1 produces sepals, whorl 2 produces petals, whorl 3 produces stamens, and whorl 4 produces carpels. Furthermore, expression of class A genes inhibits class C genes, and expression of class C inhibits class A.   -What kind of mutation would produce carpels in whorls 1 and 4 and stamens in whorls 2 and 3? A)  defective in A B)  defective in B C)  defective in C D)  defective in A and B E)  defective in B and C -What kind of mutation would produce carpels in whorls 1 and 4 and stamens in whorls 2 and 3?


A) defective in A
B) defective in B
C) defective in C
D) defective in A and B
E) defective in B and C

F) B) and C)
G) A) and E)

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How do lymphocytes violate the general principle that all cells in an organism contain the same set of genetic information?

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Lymphocytes, which are a type of white b...

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The proteins Dorsal and Bicoid both act as morphogens in Drosophila embryogenesis. However, the establishment of the concentration gradients of each protein differs. Which of the following statements CORRECTLY describes this difference?


A) The dorsal gene is transcribed maternally while the bicoid gene is transcribed in the developing embryo.
B) The dorsal gene is transcribed in the developing embryo whereas the bicoid gene is transcribed maternally.
C) The concentration gradient of Dorsal is established through asymmetric subcellular localization whereas the concentration gradient of Bicoid is established through selective degradation.
D) The concentration gradient of Dorsal is established through asymmetric subcellular localization whereas the concentration gradient of Bicoid is established through asymmetric localization of the bicoid mRNA and thus protein.
E) The concentration gradient of Dorsal is established through differential rates of translation whereas as the concentration gradient of Bicoid is established through a transport system.

F) All of the above
G) B) and D)

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D

(a) In what sense does each person's immune system become adapted to that person's environment and to the set of antigens to which that person is exposed? (b) Explain in terms of the clonal selection theory how a person's immune system responds to and comes to be "adapted" to the person's environment and personal exposure to antigens.

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(a) Each person's immune system becomes ...

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Xenotransplantation involves transplanting tissues or organs from one species to another. Some medical researchers are exploring the possibility of transplanting pig organs into humans to address the worldwide human organ donor shortage. What strategies might help with the success of such transplantations? (Select all that apply.)


A) Create transgenic pigs that lack a sugar molecule that humans do not have for use as organ donors.
B) Inject human organ transplant recipients with a sugar molecule from pigs that they do not have prior to transplantation.
C) Treat pigs with immunosuppressive drugs prior to harvesting their organs for donation.
D) Treat human organ transplant recipients with immunosuppressive drugs following xenotransplantation.
E) Administer pig bone marrow to the human organ transplant recipient prior to transplantation.

F) All of the above
G) A) and E)

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Use the following to answer questions In the late 1940s Edward Lewis discovered mutations in the Antennapedia gene that lead to legs developing on the head of a fly instead of antenna. These mutations are dominant and lead to ectopic expression of the Antennapedia gene. -Based on these data, how would you expect the gene to be expressed in the mutant? (Select all that apply.)


A) in every segment
B) in a more anterior segment
C) in a more posterior segment
D) earlier
E) later

F) A) and C)
G) A) and B)

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