THIS IS NOT THE EXAM REVIEW SHEET! HELLO EVERYONE!!! These are questions from old exams that are (mostly) relavent to Exam 2. I understand that there are many... however, these are a helpful resource. I highly recommend running through all of them (maybe try answering 25-50 per day?) These questions are directly copied and pasted from a folder on blackboard posted by your professors.

Multicellularity/specialization27. Which of the following is an example of extracellular matrix a. Collagen b. Fibronectin c. Chitin *d. All of the above e. None of the above 28. Which of the following is a function of the extracellular matrix (ECM)? a. Strengthening cell-cell and tissue-tissue contacts b. Providing support. Tissues such as bone are largely ECM. c. Mediating cell signaling *d. All of the above e. None of the above

29. Which of the following is true of the plant cell wall? a. It forms a barrier making plant cells resistant to osmotic lysis. b. A major component is cellulose. c. A major component is glucose. d. It is composed of a primary and a secondary cell wall, each with distinctive properties. *e. All of the above f. None of the above

30. Which of the following is true of the plant cell wall? a. It strengthens cell-cell and tissue-tissue contacts. b. A major component is cellulose. c. A major component is glucose. *d. All of the above e. None of the above

31. Which of the following is true about collagen? a. It is a triple helix made up of identical subunits. b. It is a triple helix made up of different types of subunits. c. There are at least 27 different collagen proteins in humans.

d. Differential gene expression helps regulate which collagens are expressed in specific tissues and locations in the body. *e. All of the above f. None of the above

32. Given the information in the table above, which of the following is a reasonable conclusion?a. All collagens have similar physical characteristics.b. Collagens only form long fibers.c. Collagens are not found throughout the body.*d. Collagens are found in the extracellular matrix of cells. 33. Given the information in the table above, which of the following is a reasonable conclusion?a. All collagens have similar physical characteristics.*b. Collagens form fibers that can be rigid, flexible, elastic, or form meshworks.c. Collagens are not found throughout the body.d. Collagen fibers are found within cells.

34. Why would it be important to have epithelial layers lining compartments such as the intestine? a. For cellular communication via gap junctions *b. To strictly control what substances cross the barrier c. To create a smooth surface d. To secrete ECM molecules onto the surface e. A  and C

35.Which of the following statements about the extracellular matrix is most correct? a. It is composed of living cells. b. It is a site of electron transport. c. It is composed of lipopolysaccharides. d. It is a static, rigid structure.

*e. Its components are produced and secreted by the cell.  36. Tight junctions - a. connect the cytoplasm of one cell to another. b. are composed of pectin. c. connect cells to the extracellular matrix. *d. form seals that prevent solutes from diffusing in between cells. e. pair chromosomes during meiosis.

37. All but which of the following are involved in physically holding cells together? a. Extracellular matrix b. anchoring junctions *c. paracrine ligands d. middle lamella e. cell adhesion molecules

38. Which of the following processes are important for normal development? a. cell division b. cell migration c. cell differentiation d. programmed cell death e. A,B,C *f. all of the above

39. The kidneys are able to regulate salt concentration in the blood because a. the endoplasmic reticulum performs dialysis b. osmosis concentrates salt in kidney cells *c. sodium transporters pump Na+ ions across the epithelium separating capillary blood from renal ducts d. electron transport produces a negative charge that attracts Na+ ions e. Na+ is selectively filtered through the extracellular matrix

40. Cellulose is *a. found in the plant extracellular matrix b. a component of the cytoskeleton c. associated with DNA to form chromosomes d. produced in chloroplasts e. a type of proteoglycan

41. The figure above from your textbook shows some of the features of collagen synthesis and assembly. Which of the following is a true statement?a. Collagen fibers consist of a bundle of collagen fibrils made up of a single collagen molecule.b. Collagen is initially synthesized as a procollagen that is then assembled into large multimeric macromolecules in the cell.*c. Procollagen assembles into collagen fibrils after removal of the extension sequences.d. Procollagen synthesis does not require a signal sequence.

42. The figure above from your textbook shows some of the features of collagen synthesis and assembly. Which of the following is a true statement?a. Collagen fibers consist of a bundle of collagen fibrils made up of a single collagen molecule.b. Collagen is initially synthesized as a procollagen. Procollagen is then assembled into large multimeric macromolecules in the cell.c. Procollagen spontaneously assembles into collagen fibrils.*d. Procollagen synthesis requires a signal sequence.

43. The figure above from your textbook shows some of the features of collagen synthesis and assembly. Which of the following is a true statement?a. Collagen fibers consist of a bundle of collagen fibrils made up of a single collagen molecule.*b. Collagen is initially synthesized as a procollagen that is then exported from the cell.

c. Procollagen spontaneously assembles into collagen fibrils.d. Procollagensynthesis does not require a signal sequence.

44. What is the purpose of cell-cell junctionsa. To keep the extracellular matrix from breaking*b. To link cells together in various waysc. To facilitate the movement of cellsd. To make sure that cells will obtain food 45. Which types of cell-cell junctions allow form a seal between intestinal epithelial cells?*a. Tight junctionsb. Anchoring junctionsc. Gap junctions

46. Which types of cell-cell junctions allow for the passing of small molecules between cells?a. Tight junctionsb. Anchoring junctions*c. Gap junctions

47. Which types of cell-cell junctions have close assocations with the cytoskeleton?a. Tight junctions*b. Anchoring junctionsc. Gap junctions

48. The figure above is from your textbook. It shows an electron micrograph of two intestinal epithelial cells from an experiment where lanthanum, an electron dense element, was injected into the bloodstream of a mouse. What outcome would you predict if the mouse was fed lanthanum rather than injected with it?a. The lanthanum would be observed on both sides of the tight junction.*b. The lanthanum would be observed on the apical side of the tight junction.c. The lanthanum would be observed on the basal side of the tight junction.d. The lanthanum would not be seen as it would be degraded in the digestive tract.

49. Which of the following statements about epithelial cells is true? a. Epithelia are only found on the outer surfaces of organisms. b. Epithelia are a single cell layer thick. *c. Epithelia are tightly adherent cells. d. All of the above e. None of the above

50. Most multicellular organisms have which of the following? a. An outer cell layer that separates the organism from the environment. b. Cell-cell communication c. A transport system that allows fluids to move within the organism. *d. All of the above e. None of the above

51. What is a function of the extracellular matrix? a. To support the organism b. To help arrange cells in space c. To help cells sense and respond to environmental changes *d. All of the above

e. None of the above 

52. Pattern formation involves which of the following? a. Axis information provided by the mother b. Cell-cell communication c. Gradients of morphogens d. The influence of gravity *e. All of the above f. None of the above

53. Pattern formation involves which of the following? a. The expression of homeotic genes b. Differential gene expression c. Communication of anterior-posterior and dorsal-ventral axis information d. The influence of gravity *e. All of the above f. None of the above

54. Which of the following statements is true? a. A finger muscle cell and a finger skin cell express similar pattern formation genes, but the muscle expresses mesoderm genes and the skin cell expresses endoderm genes. b. An arm neuron and a leg skin cell express different pattern formation genes, but both expressed common endoderm genes before diverging into neuronal and epidermal lineages. *c. Morphogens function in a concentration-dependent manner. d. Once cells occupy a specific region in the embryo, they differentiate only based on their history or lineage.

55. Which of the following statements illustrate the principle of differential gene regulation? a. Neurons have a different mRNA profile than muscle cells. b. Only a subset of cells will respond to the presence of a hormone. c. Many cells express the same set of actin proteins, but at different levels. *d. All of the above e. None of the above

56. In extracellular cellular matrix (ECM), Elastin protein: a. provides tensile strength *b. provides elasticity c. provides both strength and elasticity d. none of the above

57. In extracellular cellular matrix (ECM), collagen protein: *a. provides tensile strength b. provides elasticity c. provides both strength and elasticity d. none of the above

58. What is the major component in plant cell wall: a. Collagen b. Elastin *c. Cellulose d. Chlorophyll

59. In animal cells, the cell junctions can be: a. Anchoring junctions b. Tight junctions c. Gap junctions *d. All of the above

60. In anchoring junctions, there are two kinds of cell adhesion molecules (CAMs), cadherin and integrin. The function of integrin is: a. to create cell-to-cell junctions *b. to create connections between cells and ECM (extracellular matrix) c. to mediate both cell-to-cell and cell-to-ECM interactions d. None of the above

61. In anchoring junctions, there are two kinds of cell adhesion molecules, cadherin and integrin. The function of cadherin is: *a. to create cell-to-cell junctions b. to create connections between cells and ECM (extracellular matrix) c. to mediate both cell-to-cell and cell-to-ECM interactions d. None of the above

62. Gap junctions function to: a. Connect cells to the extracellular matrix *b. Permit the passage of molecules from the cytoplasm of one cell to another c. Form tight seals that prevent extracellular fluids from leaking between cells d. None of the above

63. Tight junctions function to: a. Connect cells to the extracellular matrix b. Permit the passage of molecules from the cytoplasm of one cell to another *c. Form tight seals that prevent extracellular fluids from leaking between cells

d. None of the above

Development64. During limb formation, which is NOT true: a. Cell division promotes the growth of the limb b. Cell migration causes cells to reach to their correct location c. Cell differentiation produces specialized cells d. Apoptosis eliminates cells in between the fingers *e. Cells undergo meiosis

65. Pattern formation during development can be determined/influenced by: a. Morphogens b. Cell contacts c. Cell signaling *d. All of the above

66. Which is not true about Bicoid: a. is a morphogen that regulates Drosophila embryo polarity b. the gene is transcribed in nurse cells and transported into anterior end of Oocyte c. is a transcription factor *d. Mutation of its genes leads to embryos with two heads

67. Drosophila embryos have 15 segments, the identity of which is determined by: a. Bicoid b. Gap genes c. Pair-rule genes d. Segment-identify genes *e. A transcriptional hierarchy of Bicoid/Gap genes/Pair-rule genes/Segment identity genes

68. The segment identity gene, Bithorax, determines that two wings form in the 2nd thoracic segment, in the bithorax mutant, there are: a. 2 wings at 2nd thoracic segment b. 2 wings at 3rd thoracic segment *c. 2 wings at 2nd thoracic segment and 2 wings at 3rd thoracic segment d. None of the above

69. If the homeotic gene Antennapedia is ectopically expressed in embryonic segment that gives rise to antenna, the fly will have: *a. legs form in the place for antenna b. legs everywhere c. legs in abdomen d. None of the above

70. Above is a model for flower patterning in Arabidopsis. If you mutate C function gene (AG), what the four wholes will be:a. Sepal-Petal-Stamen-Carpelb. Sepal-Sepal-Petal-Petalc. Sepal-Petal-Sepal-Petal*d. Sepal-Petal-Petal-Sepal

71. The figure shown above represents the chromosome locations and expression patterns of homeotic genes (Hox or Hom genes) in Drosophila and mice. Which of the following statements is consistent with the information shown?a. Mice have more Hox genes than Drosophila.b. The anterior to posterior expression patterns of Hox gene expression is conserved.c. The Abdominal B genes were likely duplicated multiple times over the course of evolution.*d. All of the abovee. None of the above

72. The figure shown above illustrates the expression domains of homeotic genes (Hox genes) in chickens and mice. Which of the following statements is consistent with the information shown?a. Chickens and mice express similar sets of Hox genes in the same anterior to posterior order.b. The different body morphologies between mice and chickens is due in part to changing the domains of the expression of Hox genes.c. The locations of forelimbs and hindlimbsis governed by conserved mechanisms in vertebrates.*d. All of the abovee. None of the above

73. The figure shown above illustrates the expression domains of homeotic genes in Arabidopsis. What would the pattern of structures be (Whorl 1 to Whorl 4) for a loss-of-function mutant in B?a. Sepals, Petals, Stamens, Carpelsb. Sepals, Sepals, Stamens, Stamens*c. Sepals, Sepals, Carpels, Carpelsd. Carpels, Stamens, Stamens, Carpels

74. The figure shown above illustrates the expression domains of homeotic genes in Arabidopsis. What would the pattern of structures be (Whorl 1 to Whorl 4) for a loss-of-function mutant in C? C limits the domain of expression of A.*a. Sepals, Petals, Petals, Sepalsb. Sepals, Sepals, Stamens, Stamensc. Sepals, Sepals, Carpels, Carpelsd. Carpels, Stamens, Stamens, Carpels

75. The figure shown above illustrates the expression domains of homeotic genes in Arabidopsis. What would the pattern of structures be (Whorl 1 to Whorl 4) for a loss-of-function mutant in A? A limits the domain of expression of C.a. Sepals, Petals, Stamens, Carpelsb. Sepals, Sepals, Stamens, Stamensc. Sepals, Sepals, Carpels, Carpels*d. Carpels, Stamens, Stamens, Carpels

76. A mouse lacking both copies of MyoD does not show a phenotype. It forms muscle. Based on this experiment, what could you conclude about the function of MyoD? a. MyoD is sufficient for muscle cell differentiation under these conditions. b. MyoD is NOT sufficient for muscle cell differentiation under these conditions. c. MyoD is necessary for muscle cell differentiation under these conditions. *d. MyoD is NOT necessary for muscle cell differentiation under these conditions.

77. What has happened in the mutant larva (b), a loss of function situation, to result in the phenotype shown?a. a DNA mutation caused bicoid to be over-expressed, causing both ends to become posterior*b. a DNA mutation caused bicoid to not be expressed, causing both ends to become posteriorc. the normal larva was transformed into one with two spiraclesd. All of the abovee. None of the above

78. Shoot lateral meristems are……(Finish the sentence) a. totipotent stem cells *b. pluripotent stem cells c. bipotent stem cells d. determined cells e. All of the above f. None of the above 79. Root meristems are……(Finish the sentence) a. totipotent stem cells *b. pluripotent stem cells c. bipotent stem cells d. determined cells e. All of the above f. None of the above

80. Shoot apical meristems are……(Finish the sentence) a. totipotent stem cells *b. pluripotent stem cells c. bipotent stem cells d. determined cells e. All of the above f. None of the above

81. A loss-of-function mutation in a Drosophila melanogaster gene called dorsal causes a pattern defect in the fly embryo. Mutant embryos are completely dorsalized; that is, dorsal structures form where there should be ventral structures. What does this tell us about the normal function of the dorsal+ gene? a. That it is required for producing dorsal structures. b. That it is not required for producing dorsal structures. *c. That it is required for making ventral structures. d. That it is not required for making ventral structures. e. None of the above.

82. A molecule that during development provides positional information via a concentration gradient is known as a a. transcription factor b. exon c. endocrine signal d. plastochron *e. morphogen

 83. Zebrafish is used as a model organism to study development because a. their embryos are almost identical to humans b. they live longer than other fish c. they have synchronous cell division cycles d. they reproduce apomictically

*e. they have rapid generation times 84. In plant development, the following is NOT true of shoot apical meristems *a. they only occur in embryos b. they involve pattern formation, morphogens, transcriptional hierarchies, progressive restriction of cell fate c. they occur at the tips of shoots and roots d. they are a self-renewing cell population (like animal stem cells) e. Continually produce organs, tissues, ect.  85. Which of the following is NOT true of homeotic genes that control the identity of flower organs? a. Mutants show changes in organ identity b. They encode transcription factors c. They function in a transcriptional hierarchy d. They function combinatorially *e. All these statements are true.

86. In plant development, what makes flower organs (petals, stamens, etc.) different from each other? a. Each inherits different genes *b. Each expresses different genes c. Each discards different genes d. Each gene codes different proteins in different organs e. Each organ inherits different morphogens.  87. Which of the following DOES NOT contribute to the differentiation of stem cell daughters? a. transcriptional hierarchy b. cell signaling c. progressive restriction of cell fate *d. altered genetic content e. altered gene expression

88. Loss-of-function mutations in a gene called Pax6 cause mammal or fish embryos to not form eyes. What is the normal function of the Pax6gene? *a. It is required for eye formation b. It blocks eye formation c. It is a morphogen d. It signals formation of an R8 cell. e. The function cannot be determined from the information given.

89. Expression of segment identity genes in Drosophila embryogenesis is determined by *a. A transcriptional hierarchy b. Stem cells c. The dorsal-ventral axis d. Mutants e. Ommatidial signaling

90. In bone marrow, there are hematopoetic stem cells (cells that generate blood) and other cells called stromal cells. Stromal cells express a protein called ”kit”. Injecting mice bone marrow with anti-kit antibodies causes inactivation of the kit protein and results in a dramatic decrease in the number of hematopoetic stem cells. The most likely function for the kit protein is a. a ribosome b. an ion channel c. a membrane receptor *d. a secreted signaling ligand e. a cell adhesion molecule

91. The Hox gene complex is a cluster of genes that a. Controls parasympathetic neural signaling b. Controls alternation of generations in plants c. Encode a signal transduction pathway that promotes oogenesis *d. Controls anterior-posterior body segment identities in vertebrates and insects e. Controls stem cell proliferation and differentiation