Definitions
Axis Formation and Patterns of Gastrulation
Patterns of Cleavage
From Fertilization to Cleavage
Cytoskeletal Mechanism of Mitosis
100
A series of mitotic divisions whereby the enormous volume of egg cytoplasm is divided into numerous small, nucleated cells
What is cleavage
100
This is the axis depicted in the picture from head to tail (2)
Anterior-posterior
100
This is the type of cleavage pictured (6)
What is radial cleavage
100
In what periods of the cell cycle does growth occur?
What is G1 and G2
100
This is the term for the division of the cell.
What is cytokinesis
200
What are the 3 major axes that are determined during cleavage and gastrulation in the embryo
Anterior-posterior (head-tail), dorsal-ventral (back-belly), left-right
200
This is the axis depicted in the picture from back to belly (3)
Dorsal-ventral
200
These are the three germ layers in order, from outermost to innermost
What is ectoderm, mesoderm, endoderm
200
The activation of this factor is key in the transition from fertilization to cleavage.
What is mitosis-promoting factor (MPF)
200
This is the term for the mitotic division of the cell’s nucleus.
What is karyokinesis
300
Cells are called this during cleavage stages
What is a blastomere
300
This picture represents the infolding of a region of cells. (3)
What is invagination
300
These are the names of the poles that are “yolk rich” and have a low yolk concentration.
What is the vegetal pole and the animal pole respectively
300
These two are responsible for controlling the INITIAL rate of cell division and the placement of the blastomeres in most species (except mammals).
What are proteins and mRNAs
300
If the contractile ring is disrupted during cleavage, this occurs.
What is cytokinesis stops
400
This is the stage in which cells are given new positions and new neighbors, and the multilayered body plan of an organism is established.
What is gastrulation
400
This picture shows the inturning of the expanding outer layer so that it spreads over the internal surface of the remaining external cells. (4)
What is involution
400
This is the term for the type of cleavage in which the cleavage furrow extends through the entire egg. Examples of animals that undergo it are sea urchins, snails, and mammals.
What is holoblastic cleavage
400
This is the larger of the two subunits for MPF and displays the cyclical behavior that is important to regulating mitosis. It is often encoded by mRNAs stored in the cytoplasm of the oocyte. If its translation is inhibited, the cell will not enter into mitosis.
What is cyclin B
400
This is the protein that makes up the microtubules of the mitotic spindle, the mechanical agent that carries out karyokinesis. This is the same protein that makes up the flagellum of sperm.
What is tubulin
500
This is the term for eggs that have sparse, equally distributed yolks.
What is isolecithal
500
This is the migration of individual cells from the surface layer into the interior of the embryo. The cells become mesenchymal and migrate independently. Also, this is the splitting of one cellular sheet into several parallel sheets. The result is a formation of a new sheet of cells. (5)
What is ingression and delamination, respectively.
500
This is the term for the type of cleavage in only a portion of the cytoplasm is cleaved because a large amount of the cell volume is made up of yolk. Examples of animals that undergo it are insects, fish, reptiles, and birds.
What is meroblastic cleavage
500
This is the smaller of the two subunits of MPF and is regulated by the larger subunit. It activates mitosis by phosphorylating target proteins, brings about the condensation of chromatin, nuclear envelope depolymerization, and organization of the mitotic spindle.
What is cyclin-dependent kinase
500
This is the mechanical agent of cytokinesis. It creates a cleavage furrow that is responsible for exerting the force that splits the zygote into two genetically equivalent blastomeres. What is it made out of?
What is a contractile ring and microfilaments made of actin
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