ZOO501 Final Term Past Papers by Dining Discussion

OBJECTIVES

1. Archenteron is used for ___________Primitive Gut
2. Spiral cleavage found in ____ Snails
3. ----------is characteristic of several animals’ groups, including annelid worms, some flatworms, and most mollusks (snails)____________ Spiral Holoblastic Cleavage
4. Cell fates are determined by signaling. The micromeres constitute a major signaling center. β- catenin is important for the inducing capacity of the ___________Micromeres.
5. Blastulae produced by radial cleavage have no blastocoel and are called______ Stereoblastulae.
6. The resulting larvae of snail is called ------ which resemble tiny bear traps_____ Glochidia
7. --------constitute a major signaling center__________ Micromeres
8. Inner surface cells thin 30x5um process ________________Filopodia.
9. The first------- divisions occur synchronously, forming a mound of cells that sits at the animal pole of a large yolk cell________12
10. Gastrulation in Snails is accomplished primarily by__________ Epiboly
11. _____is characteristic of several animals’ groups, including annelid worms, some flatworms, and most mollusks (snails). Spiral Holoblastic Cleavage
12. Cells, derived from the micromeres, are called the__________ Primary Mesenchyme.
13. Mollusca follow which types of cleavage____________ Spiral Holoblastic Cleavage
14. A mammalian blastula is called a_____________ Blastocyst.
15. The blastomere cell cycle is governed by the synthesis and degradation of _____Cyclin.
16. The second step of gastrulation involves the______ Involution of The Mesoderm.
17. Multinucleated type of cell form-_____________ Cyncytiotrophoblast
18. The first cell movement of fish gastrulation is the --------of the blastoderm cells over the yolk________ Epiboly
19. Mother provides fetus with ______________Nutrients and Oxygen
20. The most crucial, difference between mammalian cleavage and all other types involves the phenomenon of___________ Compaction
21. The neural form ____________Keel Fish
22. They have a notochord as larvae but they lack ___________Vertebrae
23. The mammalian oocyte is released from the ovary and swept by the fimbriae into ______The Oviduct.
24. Which has two parts in cell cycle options _________Blastomere
25. Fertilization of the chick egg occurs in the ____________Oviduct,
26. After the blastoderm cells have covered about half the zebra fish yolk cell, a thickening occurs throughout the margin of the epilogizing blastoderm. This thickening is called the______

Germ Ring

27. This streak is first visible in birds as a thickening of the-------- at the posterior region of the embryo, just anterior to koller sickle__________ Epiblast
28. It secretes a ----- tunic (which gave the name "tunicates" to these creatures) ____ Cellulose
29. | will induce the uterine cells of the mammals to from the maternal portion of the placenta, the_________ Decidua.
30. Between the area pellucida and the area opaca is a thin layer of cells called the ________Marginal Zone (Or Marginal Belt).
31. The cells adjacent to the chordamesoderm, the ------- are the precursors of the mesodermal somites in the fish. ______ Paraxial Mesoderm Cells
32. The first segregation of cells within the inner cell mass results in the formation of the _____

Hypoblast (Sometimes Called the Primitive Endoderm)

33. Fertilization occurs in the -------- of the oviduct, a region close to the ovary___ Ampulla
34. This fetal organ the ---- is derived primarily from embryonic trophoblast cells. ___ Chorine
35. The fetal portion of placenta formed by ______ Chorion
36. The major structural characteristic of avian, reptilian, and mammalian gastrulation is the_________ Primitive Streak.
37. Between the blastoderm and the yolk is a space called the_____ Sub-Germinal Cavity
38. The first cleavage furrow appears centrally in the________ Blastodisc,
39. The peripheral ring of blastoderm cells that have not shed their deep cells constitutes the area _______Opaca.
40. The depression is called the __________Primitive Groove
41. cytoplasm of the blastodisc becomes the embryo, this type of meroblastic cleavage is called_______ Discoidal.
42. The mammalian oocyte is released from the ovary and swept by the fimbriae into the_____ Oviduct.
43. Identical twins share a common ______________Chorion
44. Sonic hedgehog is a type of__________ Protein
45. In birds -------differences appear crucial for distinguishing dorsal from ventral. ______ pH
46. Hox genes pattern the anterior-posterior axis and help to specify positions along that___ Axis.
47. The original type of ----- cells constitute a layer called the cytotrophoblast__ Trophoblast
48. Which type of neurulation in fish __________ Secondary
49. Hindbrain______________ Rhombencephalon
50. The telencephalon will eventually form the cerebral hemispheres, and the diencephalon will form the thalamic and -------brain regions______________ Hypothalamic
51. Which forms spinal cord, hind brain and mid brain ___________Chordamesoderm.
52. Fishes, ------, and birds undergo discoidal meroblastic cleavage, wherein the early cell divisions do not cut through the yolk of the egg. 63. The fast block, initiated by sodium influx into the cell in sea urchin_________ Reptiles
53. he rudiment of the central nervous system, is called________ Neurulation.
54. Fraternal twins are the result of ------separate fertilization events_________ Two
55. The prechordal ------induces the formation of the forebrain; the chordamesoderm induces the formation of the midbrain, hindbrain, and spinal cord__________ Plate
56. About ------- of identical twins have two complete and separate chorions_______33%
57. Identical twins occur in roughly -------- of human births. _________ 0.25%
58. Mammals undergo holoblastic ---------cleavage, _____________ Rotational
59. In birds, ----------- is critical in determining the anterior-posterior axis _________ Gravity
60. The decidua becomes rich in the blood vessels that will provide --------and nutrients to the embryo. ______ Oxygen
61. In amphibians most of the xenopus most of tadpole is formed by ---------and tail of neural tube formed by 2ndry neurulation. _________ Primary Neurulation
62. Neural fold migrates to midline of embryo and fusing to form -------- beneath the overlying ectoderm. _________ Neural Tube
63. In frogs and chicks, ---------- is usually seen in the neural tube of the lumbar (abdominal) and tail 48. vertebrae. ____________ Secondary Neurulation
64. Which type of neurulation in fish____________ Exclusively Secondary.
65. Secondary neurulation involves the making of a -------- and its subsequent hollowing into a neural tube. _________ Medullary Cord
66. In primary neurulation, the original ectoderm is divided into ----- sets of cells___ Three