The primitive streak is derived from epiblast cells and the central cells of Koller’s sickle. As the primitive streak extends rostrally, Henson’s node is formed. Following are few statements regarding this:

A. As endodermal ingression continues, the primitive streak starts to regress, moving Henson’s node from near the center of the area pellucida to a more posterior position.

B. As endodermal ingression continues, the primitive streak starts to regress, moving Henson’s node from near the periphery of the area pellucida to a more posterior position.

C. As mesodermal ingression continues, the primitive streak starts to regress, moving Henson’s node from near the center of the area pellucida to a more posterior position.

D. As mesodermal ingression continues, the primitive streak starts to regress, moving Henson’s node from near the periphery of the area pellucida to a more anterior position.

Which of the following statements are correct?

#Question id: 9593

#Unit 6. System Physiology – Plant

The lower-energy orbital of the positively charged oxidized reaction centre chlorophyll has a vacancy and can accept an electron If the acceptor molecule donates its electron back to the reaction centre chlorophyll, What will happened?

#Question id: 9594

#Unit 6. System Physiology – Plant

The first reaction that converts electron energy into chemical energy—What will happened in  the primary photochemical event—

#Question id: 9595

#Unit 6. System Physiology – Plant

The process is that the absorbed photon causes an electron rearrangement in the reaction centre chlorophyll, followed by an electron transfer process in which part of the energy in the photon is captured in the form of

#Question id: 9596

#Unit 6. System Physiology – Plant

The reaction centre chlorophyll is transiently in an oxidized state after losing an electron and before being re-reduced by its electron donor, what characteristics has been shown by chlorophylls in an oxidized state?

#Question id: 9597

#Unit 6. System Physiology – Plant

The reaction centre bacteriochlorophyll from purple photosynthetic bacteria was similarly identified as-

#Question id: 9598

#Unit 6. System Physiology – Plant

In the oxidized state, reaction centre chlorophylls contain an unpaired electron, Molecules with unpaired electrons can often be detected by a magnetic-resonance technique known as