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

Developmental Biology (ZOO501)

Multiple Choice Questions (MCQs)

Objective Questions

  1. The cells adjacent to the chordamesoderm, the paraxial ________ cells, are the presursors of the mesodermal somites.

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

    1. amphibians
    2. birds and reptiles
    3. mammals
    4. None of the given
  3. 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
  4. The lateral lips of the blastopore comprise those cells that will become ________.

    1. Parenchyme
    2. Mesenchyme
    3. Photosynthetic parenchyme
    4. Storage Parenchyme
  5. 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
  6. 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
  7. In Nematode cleavage is ________.

    1. Bilateral
    2. Radial
    3. Spiral
    4. Rotational
  8. 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
  9. The original type of trophoblast cells constitute a layer called the ________.

    1. Cytotrophoblast
    2. Ectotrophoblast
    3. Mesotrophoblast
    4. Endotrophoblast
  10. 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
  11. A ________ is a cell derived from cleavage in an early embryo.

    1. Blastomere
    2. Ectoderm
    3. Endoderm
    4. Mesoderm
  12. Chorion is derived from ________ cells.

    1. hypoblast
    2. epiblast
    3. trophoblast
    4. All of the given
  13. 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
  14. 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
  15. 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
  16. 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
  17. The cytotrophoblast initially adheres to the ________ through a series of adhesion molecules.

    1. Endometrium
    2. Ectometrium
    3. Mesometrium
    4. Cytometrium
  18. In Tunicate the second Cleavage ________.

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