The hypostome acted as an “organizer” of the hydra. This notion has been confirmed by:

A. when transplanted, the hypostome can induce host tissue to form a second body axis.

B. the hypostome do not produces the head inhibition signal.

C. the hypostome is the only “self-differentiating” region of the hydra.

D. the hypostome produces a “head activation signal” that suppresses the formation of new organizing centers.

Which one of the following combinations are incorrect?

#Question id: 7290

#Unit 5. Developmental Biology

Following figure regarding to regulatory network in the Arabidopsis shoot meristem stem-cell niche.

A. The transcription factor WUS is synthesized in the cell A and moves via plasmodesmata into cell B, where one of its functions is to induce expression of the CLV3.

B. The transcription factor CLV3 is synthesized in the cell A and moves via plasmodesmata into cell B, where one of its functions is to induce expression of the WUS.

C. Secreted CLV3 protein from cell B binds to the receptor protein kinase on the surface of cell A; there, it activates a signal that represses WUS transcription.

D. Secreted WUS protein from cell B binds to the receptor protein kinase on the surface of cell A; there, it activates a signal that represses CLV3 transcription.

Which of the following combination is correct?

#Question id: 7291

#Unit 5. Developmental Biology

Five different genes are known to specify floral organ identity in Arabidopsis: APETALA1 (AP1), APETALA2 (AP2), APETALA3 (AP3), PISTILLATA (PI), and AGAMOUS (AG).

Which one of the following statement is incorrect?

#Question id: 7292

#Unit 5. Developmental Biology

How is plant cell cytokinesis different from animal cell cytokinesis?

#Question id: 7293

#Unit 5. Developmental Biology

In agamous mutant (flower within flower phenotype) which of the following statements is valid?

#Question id: 7294

#Unit 5. Developmental Biology

Multiple factors regulate flowering in Arabidopsis. FT mRNA is expressed in companion cells of the leaf vein in response to multiple signals, including day length, light quality, and temperature. FT moves in the phloem from leaves to the apical meristem. FT is unloaded from the phloem in the meristem and interacts with FD.

FT-FD complex activates multiple genes. Which of the following combination is correct?(SS)

#Question id: 7295

#Unit 5. Developmental Biology

If a long-day plant has a critical night length of 9 hours, which 24-hour cycle would prevent flowering? (SS)