Following statements regarding to the Ectodermal competence and the ability to respond to the optic vesicle inducer in Xenopus.

A. The optic vesicle is able to induce lens formation in the posterior portion of the ectoderm but not in the anterior portion.

B. If the optic vesicle is removed, the surface ectoderm forms either an abnormal lens or no lens at all.

C. Only head ectoderm is competent to respond to the signals from the optic vesicle by producing a lens.

D. The head ectoderm appears to secrete two paracrine factors BMP 4 and FGF8, which involves in the activation of lens-specific genes such as crystallin.

Which of the following combination is incorrect?

#Question id: 9618

#Unit 9. Diversity of Life Forms

Generally, within a lineage, the largest number of shared derived characters should be found among two organisms that are members of the same

#Question id: 9619

#Unit 9. Diversity of Life Forms

A common ancestor for both species C and E could be at position number 

#Question id: 9620

#Unit 9. Diversity of Life Forms

The two extant species that are most closely related to each other are

#Question id: 9621

#Unit 9. Diversity of Life Forms

If this evolutionary tree is an accurate depiction of relatedness, then which of the following should be correct?

1. The entire tree is based on maximum parsimony.

2. If all species depicted here make up a taxon, this taxon is monophyletic.

3. The last common ancestor of species B and C occurred more recently than the last common ancestor of species D and E.

4. Species A is the direct ancestor of both species B and species C.

5. The species present at position 3 is ancestral to C, D, and E

#Question id: 9622

#Unit 9. Diversity of Life Forms

Which of the following numbers represents a polyphyletic taxon? 

#Question id: 10127

#Unit 6. System Physiology – Plant

In higher plants, the multi-subunit protein supercomplex has two complete reaction centers and some antenna complexes. The core of the reaction center consists of two membrane proteins known as D1 and D2, Which contained a multi-subunit protein supercomplexes;