Formation of Germ Layers and Fertilization

<p>Two identical chromatids for each chromosome. (D)</p> Signup and view all the answers

<p>One chromosome from each pair moves to opposite ends of the spindle. (D)</p> Signup and view all the answers

<p>44 + X + X chromosomes. (A)</p> Signup and view all the answers

<p>One chromosome derives from the mother and the other from the father. (C)</p> Signup and view all the answers

<p>Cleavage. (A)</p> Signup and view all the answers

<p>Morula (B)</p> Signup and view all the answers

<p>Ectoderm and endoderm (A)</p> Signup and view all the answers

<p>Somatopleuric mesoderm and trophoblast (D)</p> Signup and view all the answers

<p>Fluid (A)</p> Signup and view all the answers

<p>Amniotic cavity (B)</p> Signup and view all the answers

<p>Prochordal plate (A)</p> Signup and view all the answers

<p>It takes the shape of a cyst. (A)</p> Signup and view all the answers

<p>Development of the mesoderm (D)</p> Signup and view all the answers

<p>8-cell stage (D)</p> Signup and view all the answers

<p>After cleavage (C)</p> Signup and view all the answers

<p>22 + X and 22 + Y (D)</p> Signup and view all the answers

<p>Embryonic pole (B)</p> Signup and view all the answers

<p>Blastocoele (C)</p> Signup and view all the answers

<p>Trophoblast (A)</p> Signup and view all the answers

<p>Zona pellucida (D)</p> Signup and view all the answers

<p>20% (A)</p> Signup and view all the answers

<p>Cleavage (D)</p> Signup and view all the answers

<p>4-cell stage (A)</p> Signup and view all the answers

<p>Mulberry (C)</p> Signup and view all the answers

<p>Trophoblast (B)</p> Signup and view all the answers

<p>Gonadotropins (A)</p> Signup and view all the answers

<p>Morula (D)</p> Signup and view all the answers

<p>Extraction of the ovum and fertilization outside the body (B)</p> Signup and view all the answers

<p>Embryo (B)</p> Signup and view all the answers

<p>They help maintain stem cells in an undifferentiated state. (A)</p> Signup and view all the answers

<p>Extra-embryonic mesoderm (D)</p> Signup and view all the answers

<p>Elimination of immune response against transplanted tissues. (B)</p> Signup and view all the answers

<p>Various types of adult cells, e.g., neurons and blood cells. (C)</p> Signup and view all the answers

<p>Adult tissues such as bone marrow and brain. (A)</p> Signup and view all the answers

<p>To produce genetically matched tissues for patients. (A)</p> Signup and view all the answers

<p>It allows the stem cell to produce tissues compatible with the patient. (C)</p> Signup and view all the answers

<p>Through exposure to specific growth factors. (C)</p> Signup and view all the answers

<p>They are difficult to culture in laboratories. (B)</p> Signup and view all the answers

<p>It is seen as a violation of natural laws. (D)</p> Signup and view all the answers

<p>Establishment of the primitive streak. (A)</p> Signup and view all the answers

<p>At day 4. (A)</p> Signup and view all the answers

<p>Environmental toxins. (A)</p> Signup and view all the answers

<p>2nd week. (C)</p> Signup and view all the answers

<p>Marks the onset of gastrulation. (C)</p> Signup and view all the answers

<p>Teratogens. (D)</p> Signup and view all the answers

Fertilization of an ovum occurs in the ampulla of the uterine tube.

The fertilized ovum undergoes cell divisions (cleavage), and when it has 16 cells, it's a morula.

A morula develops into a blastocyst, containing an inner cell mass and trophoblast.

An embryonic disc with ectoderm, endoderm, and mesoderm arises from the inner cell mass, forming the three germ layers.

A cavity develops on the ectodermal side of the embryonic disc, forming the amniotic cavity.

A cavity forms on the endodermal side of the disc, called the yolk sac.

The trophoblast and underlying mesoderm create the chorion membrane.

Cells from the primitive streak differentiate into mesoderm, the middle germ layer between the ectoderm and endoderm.

DNA replication creates a second chromatid, making each chromosome double-stranded, ready for division.

The full set of chromosomes, restored to 46 after fertilization of egg and sperm.

The sex of a child is decided at fertilization. X-bearing sperm leads to a girl; Y-bearing, to a boy.

Human cells have 23 pairs of chromosomes. One chromosome from each pair comes from each parent.

The process where each chromosome splits into two, each containing identical genetic material

The spindle is a structure that forms in the cell during division to help move chromosomes.

The fertilized egg dividing into multiple cells. This is a key step after fertilization.

Sperm containing an X chromosome resulting in female offspring.

Cells produced after a parent cell divides.

A protective layer surrounding the oocyte or the embryo in the early stages of development.

A solid ball of cells formed during early embryonic development, resembling a mulberry.

Fertilization of an egg outside the body.

The inner cell mass of the blastocyst, which will develop into the embryo.

The outer layer of cells in a blastocyst that will form the placenta and other extra-embryonic tissues.

A baby conceived using in vitro fertilization (IVF).

The environment where fertilization and early embryo development occur.

Embryo placed inside the uterus after reaching this eight-celled stage during development.

Only about 20% of embryo transfers result in successful implantation.

Each egg cell (ovum) contains 22 chromosomes plus an X chromosome.

Sperm cells are categorized into two types based on their chromosome content (22+X or 22+Y).

The blastocyst has an embryonic (animal) pole where the inner cell mass attaches, and an abembryonic pole.

The zona pellucida prevents the embryo from sticking to uterine tissues while it travels to the uterus.

A thickened band of cells that forms on the dorsal surface of the embryonic disc during gastrulation. It is crucial for establishing the body axis and initiating development of the mesoderm.

The middle germ layer that arises from the primitive streak during gastrulation. It will give rise to various tissues and organs in the developing embryo, including muscle, bone, and blood.

Mesoderm that arises outside the embryo, specifically from the connecting stalk. It contributes to the development of structures like the amnion and chorion, supporting the growing embryo.

A structure attaching the embryo to the placenta. It contains blood vessels and serves as a conduit for nutrient exchange and waste removal.

The cavity that forms within the extra-embryonic mesoderm, surrounding the amnion and yolk sac. It plays a role in separation and protection of these structures.

A technique where the nucleus of a patient's cell is introduced into an embryonic stem cell, creating cells genetically identical to the patient. These cells can then differentiate into various cell types for treating diseases.

The process where stem cells, with potential to become various cell types, develop into specific types of cells like neurons, muscle cells, or blood cells, depending on the environmental factors.

Stem cells found in some adult tissues like bone marrow, brain, and skeletal muscle, with limited potential to differentiate into different cell types, compared to embryonic stem cells.

The first two weeks of pregnancy where the embryo develops but no organs are formed.

The embryo starts as a flat, two-layered structure with an outer ectoderm layer and an inner endoderm layer.

The process where the bilaminar disc transforms into a three-layered structure called the trilaminar disc.

The three-layered embryo structure formed during gastrulation, consisting of ectoderm, mesoderm, and endoderm.

The outer layer of the trilaminar disc that forms the skin, hair, and nervous system.

The middle layer of the trilaminar disc that forms muscles, bones, and the circulatory system.

The inner layer of the trilaminar disc that forms the lining of the digestive tract and lungs.

Birth defects that occur during embryonic development, often due to teratogens.