GRE Subject Test: Biochemistry, Cell, and Molecular Biology › Differentiation
Which of the following growth factors is primarily produced by the kidney and is essential for the production of red blood cells?
Erythropoietin
Insulin-like growth factor
Angiopoietin
Myostatin
Fibroblast growth factor
Erythropoietin is a glycoprotein that is crucial for the production of red blood cells, a process also called "erythropoiesis." Each of the other answers contains a growth factor, but none of these have a primary function in red blood cell production.
Which of the following growth factors is primarily produced by the kidney and is essential for the production of red blood cells?
Erythropoietin
Insulin-like growth factor
Angiopoietin
Myostatin
Fibroblast growth factor
Erythropoietin is a glycoprotein that is crucial for the production of red blood cells, a process also called "erythropoiesis." Each of the other answers contains a growth factor, but none of these have a primary function in red blood cell production.
Which of the following terms describes when the single germ layered blastula reorganizes into a structure with mesoderm, endoderm, and ectoderm germ layers?
Gastrulation
Blastulation
Somiteogenesis
Myogenesis
Morphogenesis
The correct answer is gastrulation. Gastrulation occurs through five stages (1. invagination 2. involution 3. ingression 4. delamination 5. epiboly) and results in the formation of a gastrula with the mesoderm, endoderm, and ectoderm germ layers. Blastulation is the formation of the single germ layered blastula, which is a process that precedes gastrulation. Somiteogenesis forms somites in developing embryos to give rise to the future spine. Myogenesis is the formation of muscle tissue. Morphogenesis is the process of an organism forming its shape, driven by cell cycle progression, differentiation, and subsequent development of organs and appendages.
Which of the following terms describes when the single germ layered blastula reorganizes into a structure with mesoderm, endoderm, and ectoderm germ layers?
Gastrulation
Blastulation
Somiteogenesis
Myogenesis
Morphogenesis
The correct answer is gastrulation. Gastrulation occurs through five stages (1. invagination 2. involution 3. ingression 4. delamination 5. epiboly) and results in the formation of a gastrula with the mesoderm, endoderm, and ectoderm germ layers. Blastulation is the formation of the single germ layered blastula, which is a process that precedes gastrulation. Somiteogenesis forms somites in developing embryos to give rise to the future spine. Myogenesis is the formation of muscle tissue. Morphogenesis is the process of an organism forming its shape, driven by cell cycle progression, differentiation, and subsequent development of organs and appendages.
During asymmetric cell division, cells divide such that the mitotic spindles are oriented perpendicular to the plane on which the cells reside. What types of cells are the original parent cells and how does this affect cell lineage?
Asymmetric cell division begins the differentiation process from "parent" stem cells
Asymmetric cell division begins the differentiation process from "parent" immune cells
Asymmetric cell division is proliferation from "parent" differentiated cells
Asymmetric cell division begins the de-differentiation process from "parent" differentiated cells
Asymmetric cell division is proliferation process "parent" stem cells
The correct answer is that asymmetric cell division begins the differentiation process from "parent" stem cells. Symmetric cell division generates two identical daughter cells that have mitotic spindles oriented parallel to the plane on which the cells reside. However, cells that begin a differentiation lineage undergo asymmetric cell division. The perpendicularity of the mitotic spindle in cells that eventually differentiate contributes to this process.
During asymmetric cell division, cells divide such that the mitotic spindles are oriented perpendicular to the plane on which the cells reside. What types of cells are the original parent cells and how does this affect cell lineage?
Asymmetric cell division begins the differentiation process from "parent" stem cells
Asymmetric cell division begins the differentiation process from "parent" immune cells
Asymmetric cell division is proliferation from "parent" differentiated cells
Asymmetric cell division begins the de-differentiation process from "parent" differentiated cells
Asymmetric cell division is proliferation process "parent" stem cells
The correct answer is that asymmetric cell division begins the differentiation process from "parent" stem cells. Symmetric cell division generates two identical daughter cells that have mitotic spindles oriented parallel to the plane on which the cells reside. However, cells that begin a differentiation lineage undergo asymmetric cell division. The perpendicularity of the mitotic spindle in cells that eventually differentiate contributes to this process.
Homeobox (Hox) genes are essential regulators of development of an organism, as they define region specific development of an embryo along its anterior-posterioir axis. A mutation in the gene Antennapedia, for example, causes Drosophila melanogaster to grow legs from its head instead of antennae.
Given that hox genes regulate segmental identity of an organism, which of the following phenotypes would possibly be present in a fruit fly with a mutation in a Hox gene required for formation of very anterior structures?
Head missing or malformed
Extra wing appendages
Missing wing appendages
Genital structures missing
Extra legs extending from thorax
The only 'very anterior' structure listed among the answers is the head. If this particular hox gene is required to create the proper anterior appendage, we can predict that of the structures listed the head is most likely to be affected.
Homeobox (Hox) genes are essential regulators of development of an organism, as they define region specific development of an embryo along its anterior-posterioir axis. A mutation in the gene Antennapedia, for example, causes Drosophila melanogaster to grow legs from its head instead of antennae.
Given that hox genes regulate segmental identity of an organism, which of the following phenotypes would possibly be present in a fruit fly with a mutation in a Hox gene required for formation of very anterior structures?
Head missing or malformed
Extra wing appendages
Missing wing appendages
Genital structures missing
Extra legs extending from thorax
The only 'very anterior' structure listed among the answers is the head. If this particular hox gene is required to create the proper anterior appendage, we can predict that of the structures listed the head is most likely to be affected.
Which of the listed processes are part of gastrulation?
The formation of the primitive streak that undergoes epithelial to mesenchymal transition
The invagination of the notochord to induce the formation of the neural plate
The formation of ectoderm and endoderm germ layers in radially symmetric organisms
The ingression of cells from the epiblast to form a circular blastocyst
Gastrulation is the process of cells from the epiblast ingressing into the embryo to form the three germ layers of bilaterally symetrical animals. When gastrulation is complete, the embryo is referred to as a gastrula. The group of cells that lead the migration of cells into the embryo are called the primitive streak, and they undergo epithelial to mesenchymal transition to be able to migrate. You can image the epithelium as many tightly packed squares. Becomimg mesenchymal turns these cells into more malleable stage, like a soft cushion. They can then "drop" into the inner layer of the blastocyst and lead the process of gastrulation.
Which of the listed processes are part of gastrulation?
The formation of the primitive streak that undergoes epithelial to mesenchymal transition
The invagination of the notochord to induce the formation of the neural plate
The formation of ectoderm and endoderm germ layers in radially symmetric organisms
The ingression of cells from the epiblast to form a circular blastocyst
Gastrulation is the process of cells from the epiblast ingressing into the embryo to form the three germ layers of bilaterally symetrical animals. When gastrulation is complete, the embryo is referred to as a gastrula. The group of cells that lead the migration of cells into the embryo are called the primitive streak, and they undergo epithelial to mesenchymal transition to be able to migrate. You can image the epithelium as many tightly packed squares. Becomimg mesenchymal turns these cells into more malleable stage, like a soft cushion. They can then "drop" into the inner layer of the blastocyst and lead the process of gastrulation.