Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 6054
TLS Online TPP Program

#Question id: 7254

Following statements regarding to the micromeres specification and regulatory input  in sea urchin embryo. Which of the following statement is correct?

#Unit 5. Developmental Biology
  1. OTX is a general transcription factor, and β-catenin from the maternal cytoplasm is concentrated at the vegetal pole of the egg. These transcriptional regulators are inherited by the macromeres and activate the Pmar1 gene.
  2. Pmar1 encodes a repressor of HesC, which in turn encodes activator of several genes involved in micromere specification.
  3. In the veg2 cells, Pmar1 is not activated and the HesC gene product shuts down the non-skeletogenic genes.
  4. As soon as the micromeres form, maternal β-catenin and Otx activate the Blimp1 gene, whose product activates the Wnt8 gene. Wnt8 protein is then received by the same micromeres that made it (i.e., autocrine regulation), activating the micromeres’ own genes for β-catenin.
More Questions
TLS Online TPP Program

#Question id: 1390

#Unit 4. Cell Communication and Cell Signaling

Which of the following statements describes the events of apoptosis?
TLS Online TPP Program

#Question id: 5633

#Unit 5. Developmental Biology

During slow block to polyspermy, the components of the cortical granules bind to the _______ to form a fertilization envelope.
TLS Online TPP Program

#Question id: 11406

#Unit 10. Ecological Principles

Which of the following is true for a critically endangered species?
TLS Online TPP Program

#Question id: 26955

#Unit 10. Ecological Principles

Calculate the maximum sustainable yield, if given intrinsic growth rate=0.5 while K=1000
TLS Online TPP Program

#Question id: 14845

#Unit 13. Methods in Biology

Four persons are chosen at random from a group containing 3 men, 2 women and 4 children. The chance that exactly 2 of them will be children is