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TLS Online TPP Program

#Question id: 14766

Which of the following statements does not belongs to the regulatory mechanism of the Arp2/3 complex by WASp and PI(4,5)P2?

#Unit 2. Cellular Organization
  1. The NPF WASp is inactive due to an intramolecular interaction that masks the WCA domain. 
  2. NPF WASp is activated by a coincidence detection mechanism, it must bind both the regulatory phospholipid PI(4,5)P2 though its basic domain (B) and the membrane-bound active small G protein Cdc42-GTP through its Rho-binding domain. 
  3. When activated by the Cdc42-GTP, the intramolecular interaction in WASp is relieved, allowing the W domain to bind actin and the acidic A domain to activate the Arp2/3 complex.
  4. The Arp2/3 branch makes a characteristic 70° angle between the old and new filaments.
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TLS Online TPP Program

#Question id: 16142

#Unit 4. Cell Communication and Cell Signaling

Stem cells are defined by two capacities:
(1) the ability to regenerate or “self-renew” and
(2) the ability to differentiate into all diverse cell types. Embryonic stem cells have the capacity to generate every specialized cell type in an organism, in other words,
TLS Online TPP Program

#Question id: 16143

#Unit 4. Cell Communication and Cell Signaling

undifferentiated hematopoietic stem cells would not express surface markers specific for mature cells from the multiple blood lineages (“Lin” markers). They used several approaches to eliminate cells in the bone marrow that did express these markers (Lin+ cells) and then examined the remaining (Lin+) population for its potential to continually give rise to all blood cells over the long term. Lin- cells were, indeed, enriched for this potential. what marker is   express If cells inter in lymphoid lineages?
TLS Online TPP Program

#Question id: 16144

#Unit 4. Cell Communication and Cell Signaling

  _______are motile phagocytic cells they play their most important role in the defense against multicellular parasitic organisms, including worms. They can be found clustering around invading worms, whose membranes are damaged by the activity of proteins released from its granules. it may also secrete cytokines that regulate B and T lymphocytes, thereby influencing the adaptive immune response.
TLS Online TPP Program

#Question id: 16145

#Unit 4. Cell Communication and Cell Signaling

 Which line is not true for follicular dendritic cells?
TLS Online TPP Program

#Question id: 16146

#Unit 4. Cell Communication and Cell Signaling

If a given lymphocyte divides to form two daughter cells, both daughters bear antigen receptors with antigen specificities identical to each other and to the parental cell from which they arose, and so will any descendants they produce. The resulting population of lymphocytes, all arising from the same founding lymphocyte, is a clone. Which interleukin is responsible for clone production?
TLS Online TPP Program

#Question id: 16147

#Unit 4. Cell Communication and Cell Signaling

 Which statement is not true for Natural killer (NK) cells?