Question

In: Biology

which are the experiments that prove the thymus comes from only one germ layer and is...

which are the experiments that prove the thymus comes from only one germ layer and is not derived from ectoderm and endoderm?

Solutions

Expert Solution

Thymus is a bilobed primary organ essential for the generation of functional T cells and is located on the top of the heart in the central compartment of the thoracic cavity. The development of thymus is associated with small endocrine glands in the neck known as parathyroid glands that are responsible for maintaining calcium homeostasis. The embryonic development of lymphocytic components of the thymus and parathyroid glands occur from single primordia. The epithelial cells instruct the mesenchyme to participate in the thymus development. This can be understood by an experiment in which mice embryonic thymus lobes were dissociated into the epithelial primordium and capsule of mesenchymal. These two were then cultured alone or combined with mesenchyme capsule. It was observed that epithelial primordium fails to develop in the absence of mesenchymal cells. So this experiment clearly reveals the significance of epithelial-mesenchymal interactions in the morphogenesis and growth of thymus. Histological and histochemical experiments are done for understanding how the epithelial portion of the thymus derived entirely from pharyngeal pouch endoderm. Further two chick quail chimera studies have shown that mesenchymal capsules and the pericytes in the thymus are derived from neural crest cells. Experiments done on medulla consisting of clonal clusters of cells have shown that progenitor cell mechanisms are essential for thymic epithelial cells (TECs) differentiation. Labeling of the surface ectoderm coupled with whole embryo culture have shown to demonstrate that ectodermal cells do not contribute physically to the development thymus. Gene expression and genetic studies in mice have shown the involvement of many transcription factors and signaling pathways that play essential roles in thymus organogenesis.


Related Solutions

Response 1: Explain the 3 germ layers and tell one part/organ that arises from each layer...
Response 1: Explain the 3 germ layers and tell one part/organ that arises from each layer Response 2: Include 2 developmental changes associated with aging.
A Flash Translation Layer Select one: a. tracks which physical block contains only invalid pages. b....
A Flash Translation Layer Select one: a. tracks which physical block contains only invalid pages. b. translates user data to a format that can be written on the NVM. c. tracks which physical block contains only valid pages. d. tracks which physical block contains the most number of consecutive invalid pages. Which of the following is FALSE about swap space use? Select one: a. Swap space may be used to store only pages that have been pushed out of main...
Some capital equipment such as a moving assembly line only comes in one size. This usually...
Some capital equipment such as a moving assembly line only comes in one size. This usually tends to create a. a significant diseconomy of scale at the plant level b. a significant diseconomy of scale at the firm level c. a smaller MOS d. an economy of scale e. an antitrust case 6. What happens to the firm’s long run average cost (LAC) as it produces more and there is are economies of scale? a. LAC changes, but we cannot...
Prove that there is only one possible multiplication table for G if G has exactly 1,...
Prove that there is only one possible multiplication table for G if G has exactly 1, 2, or 3 elements. Analyze the possible multiplication tables for groups with exactly 4 elements, and show that there are two distinct tables, up to reordering the elements of G. Use these tables to prove that all groups with < 4 elements are commutative. (You are welcome to analyze groups with 5 elements using the same technique, but you will soon know enough about...
For each of the following experiments, cite at least one example from each of the four...
For each of the following experiments, cite at least one example from each of the four kinds of systematic errors that could affect the experiment: to. A sphere that rolls on an inclined plane, and for which the distance and time spent traveling it are measured. yes. A simple pendulum used to measure the acceleration of gravity.
Let f be a one-to-one function from A into b with B countable. Prove that A...
Let f be a one-to-one function from A into b with B countable. Prove that A is countable. Section on Cardinality
One person comes from a culture that believes “We’re all human, aren’t we?” Another person comes...
One person comes from a culture that believes “We’re all human, aren’t we?” Another person comes from a culture that says “Status is everything.” What problems might occur as these two individuals try to communicate with each other?
1. Which ONE of the following defendants is the only one in which a state court...
1. Which ONE of the following defendants is the only one in which a state court would absolutely be able to exercise in personam jurisdiction (without having to have additional information to make a determination)? a. An individual who is traveling through a state and allegedly causes damage while there. b.A business that is incorporated in somewhere in the United States. c. A business with manufacturing and distribution facilities located in multiple states throughout the country. d. An individual who...
prove that f(x)=x^2019 +x-1 has only one real root
prove that f(x)=x^2019 +x-1 has only one real root
Prove that: a) |sinx|<= |x| b) x = sin x has only one solution in real...
Prove that: a) |sinx|<= |x| b) x = sin x has only one solution in real number using mean value theorem
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT