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

Developmental Biology (ZOO501)

Multiple Choice Questions (MCQs)

Objective Questions

  1. A ________ is a cell derived from cleavage in an early embryo.

    1. Blastomere
    2. Ectoderm
    3. Endoderm
    4. Mesoderm
  2. The cells adjacent to the chordamesoderm, the paraxial ________ cells, are the presursors of the mesodermal somites.

    1. Ectoderm
    2. Mesoderm
    3. Endoderm
    4. Blastoderm
  3. The cytotrophoblast initially adheres to the ________ through a series of adhesion molecules.

    1. Endometrium
    2. Ectometrium
    3. Mesometrium
    4. Cytometrium
  4. 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
  5. In Nematode cleavage is ________.

    1. Bilateral
    2. Radial
    3. Spiral
    4. Rotational
  6. 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
  7. The lateral lips of the blastopore comprise those cells that will become ________.

    1. Parenchyme
    2. Mesenchyme
    3. Photosynthetic parenchyme
    4. Storage Parenchyme
  8. discoidal meroblastic cleavage occur in ________.

    1. amphibians
    2. birds and reptiles
    3. mammals
    4. None of the given
  9. 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
  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. 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
  12. Chorion is derived from ________ cells.

    1. hypoblast
    2. epiblast
    3. trophoblast
    4. All of the given
  13. 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
  14. The original type of trophoblast cells constitute a layer called the ________.

    1. Cytotrophoblast
    2. Ectotrophoblast
    3. Mesotrophoblast
    4. Endotrophoblast
  15. 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
  16. In Tunicate the second Cleavage ________.

    1. Meridional cleavage
    2. Bilateral cleavage
    3. Holoblastic cleavage
    4. Mesentoblastic cleavage
  17. 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
  18. 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
  19. 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
  20. 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
  21. 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