Embryogenesis -Neurolation

Question 1

It is the tudy of the prenatal development of an organism

Answer 1

Embryology

Question 2

the formation of the body structures and organs (organogenesis).

Answer 2

Embryogenesis

Question 3

an increase in the number of cells as a result of cell growth and cell division

Answer 3

Cell Proliferation

Question 4

result of cells expressing some genes and suppressing others within
a common genome.

Answer 4

Cell Differentiation

Question 5

branch of embryology that deals with the causes and results of abnormal
development or congenital malformation.

Answer 5

Teratology

Question 6

abnormality that arises during prenatal
development due to hereditary or environmental factors.

Answer 6

Congenital Malformation/Defect

Question 7

An embryo in the form of a compact ball of
blastomeres. Morula typically consists of 16 – 64 blastomeres , i.e. four to six cell divisions

Answer 7

Morula

Question 8

It develops during the 2nd week following the rupture of the zona pellucida. This consists
of a large number of blastomeres arranged to form a hollow, fluid-filled sphere/cylinder containing
an inner cell mass or embryonic disk localized inside one pole of the blastocyst

Answer 8

Blastocyst

Question 9

series of cell divisions that occurs in the zygote following fertilization.

Answer 9

Cleavage

Question 10

union of a haploid female gamete (oocyte) with a haploid male gamete
(spermatozoon) to form a diploid zygote.

Answer 10

Fertilization

Question 11

gonads in males are known as

Answer 11

Testis

Question 12

mature reproductive cells capable of fertilization

Answer 12

Gametes

Question 13

refers to the development and
maturation of female gamete (ovum)

Answer 13

Oogenesis

Question 14

refers to the maturation and
development of male gametes (spermatozoa)

Answer 14

Spermatogenesis

Question 15

transformation of spermatids to spermatozoa

Answer 15

Spermiogenesis

Question 16

Holoblastic cleavage / cleavage in mammals is a series of mitotic divisions by which a large zygote
is fractionated into numerous ”normal size” cells called

Answer 16

Blastomers

Question 17

defined as the state of embryonic development marked by rearrangement of
the cells. It is also considered a critical period of embryonic development because during this
period the potentials of a particular tissue to develop into organs begin to be restricted

Answer 17

Gastrulation

Question 18

the embryonic disk to form three (3) separate parallel tissues

Answer 18

Germ Layers

Question 19

developing organs become more sensitive to external agents that produce birth defects.

Answer 19

Teratogens

Question 20

occurs in the epiblast of the embryonic disk, a
relatively small area of the blastocyst when compared to the extraembryonic trophoblast.

Answer 20

Formation of the primitive streak

Question 21

On the epiblast surface, the primitive streak forms a differential cell growth that generates a
pair of ridges separated by a depression.

Answer 21

Formation of primitive groove and primitive folds or ridges, endoderm and Mesoderm

Question 22

closely adjacent to the overlying ectoderm of the
embryonic disk and the trophoblast.

Answer 22

Somatic Mesoderm

Question 23

closely related to the underlying
embryonic endoderm and hypoblast.

Answer 23

Splanchnic Mesoderm

Question 24

Epiblast cells in the cranial 1/3 of embryonic disc stop their mitotic activity and migrate away
as mesoderm.

Answer 24

Regression of primitive streak, formation of notochord and renaming of
surface epiblast as ectoderm.

Question 25

rod-shaped aggregate of epiblast cells located cranial to the primitive streak

Answer 25

Notochord

Question 26

epiblasts form a mass of cells

Answer 26

Paraxial Mesoderm.

Question 27

occupies the anterior border of future head.

Answer 27

Head Process

Question 28

early embryo is flat but the vertebrate body plan features a cylindrical theme.

Answer 28

Development of Cylindrical Body

Question 29

The cardiac tube originates from paired primordia in the mesoderm that eventually fuse in the middle as a result of cephalic and lateral folding of the embryo.

Answer 29

Initial Development of the Heart

Question 30

Mesoderm accumulates on each side of the notochord and is designated as paraxial mesoderm. Cells of the paraxial mesoderm become compact and arranged radially around a tiny central cavity called myocoele, which becomes enlarged later. When this occurs the paraxial mesoderm is then termed somite.

Answer 30

Sequence of Somite Development

Question 31

Somites are blocks of mesoderm derived from paraxial mesoderm located just lateral to the notochord

Answer 31

Formation of Somites

Question 32

the fifth and last stage of early embryonic development

Answer 32

Neurolation

Question 33

he epiblast cells on the surface of the embryonic disk

Answer 33

Ectoderm

Question 34

Migrates to form the skin dermis. Each dermatome forms a continuous area of skin innervated by one spinal nerve. Skin epidermis including hair follicle and glands is derived from surface ectoderm. Neural crest cells migrate into the epidermis and become melanocytes and tactile disc receptors.

Answer 34

Dermatome

Question 35

Forms most of the axial skeleton: vertebrae, ribs and bone of the skull.

Answer 35

Screlotome

Question 36

Forms skeletal musculature.

Answer 36

Myotome