Following statements are regarding to the CFTR.

A. cystic fibrosis transmembrane conductance regulator allows Cl− ions to flow out of the cell, following their concentration gradient.

B. ATP binding to CFTR’s two nucleotide-binding domains appears to close the Cl− channel, and the hydrolysis of one ATP opens it (the other ATP remains intact).

C. the CFTR channel can open only if its regulatory domain (which is unique among ABC transporters) has been phosphorylated, thus regulating the flow of ions across the membrane.

D. The maintenance of electrical neutrality requires that the Cl− ions transported by the CFTR be accompanied by positively charged ions, mainly Na+. The transported ions are osmotically accompanied by water, thus maintaining the proper level of fluidity in secretions of the airways, intestinal tract, and the ducts of the pancreas, testes, and sweat glands.

Which of the following combination is correct?

#Question id: 10208

#Unit 6. System Physiology – Plant

The large amounts of energy absorbed by the pigments if this energy cannot be stored by photochemistry, this is why a protection mechanism is needed Protection against photodamage is a multilevel process what role does the first line of defense play to suppress from damage?

#Question id: 10209

#Unit 6. System Physiology – Plant

Protection against photodamage is a multilevel process, excited state of chlorophyll is not rapidly quenched by photochemistry it can react with molecular oxygen to form toxic photoproducts such as as singlet oxygen (1 O2*) what can damage if this second line of defense also fails to eliminate the reactive photoproducts?

#Question id: 10210

#Unit 6. System Physiology – Plant

Some xanthophylls also participate in energy dissipation such as in light conversion of Violaxanthin to Zeaxanthin with antheraxanthin as the intermediate and vice-versa, which of the following statements is CORRECT?

a.) The conversion of Violaxanthin to Zeaxanthin a singlet oxygen is removed with the help of co-factor Ascorbate and violaxanthin de-epoxidase under high PPFD

b.) Zeaxanthin is oxidised into violaxanthin with the help of NADPH and oxygen under low PPFD

c.) Conversion of Violaxanthin to Zeaxanthin a singlet oxygen is removed with the help of NADPH and water under low PPFD

d.) Zeaxanthin is oxidised into violaxanthin in presence of enzyme known as violaxanthin de-epoxidase and co-factor Ascorbate under high PPFD

#Question id: 10211

#Unit 6. System Physiology – Plant

Which of the following mechanism is not involve in phtoprotection to plants?

#Question id: 10212

#Unit 6. System Physiology – Plant

Which of the following mechanism is not involve in phtoprotection to plants?

#Question id: 10213

#Unit 6. System Physiology – Plant

What is the reason behind that an organism cannot live or die in the presence of both light and molecular oxygen?