In the name of ALLAH, the most beneficient, the most merciful

Developmental Biology (ZOO501)

Multiple Choice Questions (MCQs)

Objective Questions

  1. In Tunicate cleavage during the next three divisions, differences in cell size and shape highlight the ________ of these embryos.

    1. Holoblastic
    2. Meridional
    3. Bilateral Symmetry
    4. Holos symmetry
  2. The cytotrophoblast initially adheres to the ________ through a series of adhesion molecules.

    1. Endometrium
    2. Ectometrium
    3. Mesometrium
    4. Cytometrium
  3. The first segregation in mammalian cells within the inner cell mass results in the formation of the ________.

    1. Primitive endoderm
    2. Primitive mesoderm
    3. Primitive ectoderm
    4. Primitive kit
  4. In mammalian cleavage at 64-cell stage, the inner cell mass and the ________ cells have become separate cell layers, neither contributing cells to the other group.

    1. Trophoblast
    2. Mesentoblast
    3. Cavitation
    4. Blastocyst
  5. The peripheral ring of blastodem cells that have not shed their deep cells constitutes the ________.

    1. Area pellucid
    2. Area opaca
    3. Marginal zone
    4. Marginal belt
  6. A ________ is a cell derived from cleavage in an early embryo.

    1. Blastomere
    2. Ectoderm
    3. Endoderm
    4. Mesoderm
  7. The original type of trophoblast cells constitute a layer called the ________.

    1. Cytotrophoblast
    2. Ectotrophoblast
    3. Mesotrophoblast
    4. Endotrophoblast
  8. In Tunicate the second Cleavage ________.

    1. Meridional cleavage
    2. Bilateral cleavage
    3. Holoblastic cleavage
    4. Mesentoblastic cleavage
  9. The cells adjacent to the chordamesoderm, the paraxial ________ cells, are the presursors of the mesodermal somites.

    1. Ectoderm
    2. Mesoderm
    3. Endoderm
    4. Blastoderm
  10. Tunicate gastrulation is characterized by the invagination of the endoderm, the involution of the mesoderm, and the epiboly of the ________.

    1. Endocrine
    2. Ectoderm
    3. Endoderm
    4. Mesoderm
  11. discoidal meroblastic cleavage occur in ________.

    1. amphibians
    2. birds and reptiles
    3. mammals
    4. None of the given
  12. Between the area pellucida and the area opaca is a thin layer of cells called the ________.

    1. Sub germinal cavity
    2. Egg white
    3. Albumin
    4. Marginal belt
  13. In Nematode cleavage is ________.

    1. Bilateral
    2. Radial
    3. Spiral
    4. Rotational
  14. The lateral lips of the blastopore comprise those cells that will become ________.

    1. Parenchyme
    2. Mesenchyme
    3. Photosynthetic parenchyme
    4. Storage Parenchyme
  15. Fishes, ________, and birds undergo discoidal meroblastic cleavage, wherein the early cell division do not cut through the yolk of the egg.

    1. Fishes
    2. Mammales
    3. Amphibia
    4. Reptiles
  16. The cells adjacent to the chorda-mesoderm, the paraxial mesoderm cells, are the presursors of the in ________ fish.

    1. Endodermal somites
    2. Mesodermal somites
    3. Exodermal somites
    4. Somites
  17. During mammalian cleavage the trophoblast cells secrete fluid into the morula to create a blastocoels this process called as ________.

    1. Blastocyst
    2. Cavitation
    3. Primitive kit
    4. Primitive groove
  18. The narrow connecting stalk of extra-embryonic ________ that links the embryo to the trophoblast eventually forms the vessels of the umbilical cord.

    1. Endoderm
    2. Mesoderm
    3. Ectoderm
    4. Mesentroderm
  19. The ________ that are the precursors of the neutral tube invaginate into the embryo and are enclosed by neural folds.

    1. Dorsal Endodermal Cells
    2. Dorsal Mesodermal Cells
    3. Dorsal Ectodermal Cells
    4. Dorsal Endocrine Glands
  20. Chorion is derived from ________ cells.

    1. hypoblast
    2. epiblast
    3. trophoblast
    4. All of the given
  21. Mother provides the fetus with nutrients and oxygen, and the fetus sends its waste products ________ into the maternal circulation.

    1. Carbon dioxide and urea
    2. Carbon monoxide and urea
    3. oxygen and urea
    4. Urea and oxygen