Following statements are regarding to the the floral quartet model and the underlying ABCDE model of organ identity determination in Arabidopsis thaliana.

A. Five floral organ identities (sepals, petals, stamens, carpels, and ovules) are specified by the formation of floral organ-specific tetrameric complexes of MADS-domain transcription factors that bind to two nearby enhancer elements, forming a DNA loop in between.

B. A complex of two class A proteins (APETALA 1) and two class E proteins  (SEPALLATA) determines petal identity.

C. A complex of one class A protein, one class E protein, and one of each of the class B proteins (APETALA 3 and PISTILLATA) determines sepal identity.

D. A complex of one class E protein, two class B proteins, and one class C protein (AGAMOUS) determines stamen identity, while a complex of two class E proteins and two class C proteins determines carpel identity.D. A complex of one class E protein, two class B proteins, and one class C protein (AGAMOUS) determines stamen identity, while a complex of two class E proteins and two class C proteins determines carpel identity.

E. A complex of one class E protein, one class C protein, and one of each of the class D proteins (SHATTERPROOF and SEEDSTICK) controls ovule identity.

Which of the following combination are correct?

#Question id: 10345

#Unit 6. System Physiology – Plant

In Leaf Chloroplasts and root plastids contain different forms of the enzyme, nitrite reductase such as

a) Roots contain fd-dependent nitrite reductase

b) Shoots contain NADPH dependent nitrite reductase

c) Shoots contain fd-dependent nitrite reductase

d) Roots contain NADPH dependent nitrite reductase

Which one of the following is correct combination?

#Question id: 10344

#Unit 6. System Physiology – Plant

Some of the following caracteristics of Nitrite reductase, which one of the is incorrect?

#Question id: 10342

#Unit 6. System Physiology – Plant

Nitrate reductase is an important enzyme for nitrate assimilation. Given below some regulation of nitrate reductase activity through phosphorylation and dephosphorylation.

a) Light, and other environmental factors stimulate a protein phosphatase that dephosphorylates a key serine residue in the hinge 1 region of nitrate reductase and thereby activates the enzyme

b) In Dark, and Mg2+ stimulate a protein kinase that phosphorylates the same serine residues, which then interact with a 14-3-3 inhibitor protein, and thereby inactivate nitrate reductase

c) In Light, and Mg2+ stimulate a protein kinase that phosphorylates the serine residues, and thereby activate nitrate reductase

d) In Dark, and other environmental factors stimulate a protein phosphatase that dephosphorylates a key serine residue in the hinge 1 region of nitrate reductase and thereby inactivates the enzyme

Which of the following statements about regulation of nitrate reductase is correct?

#Question id: 10339

#Unit 6. System Physiology – Plant

Nitrate assimilates into the root where the conversion of nitrate to nitrite in the cytosol, a reduction reaction that involves the transfer of two electrons catalyzes by an enzyme that is NAD(P)H dependent is known as

#Question id: 10250

#Unit 6. System Physiology – Plant

Glycolysis involves a series of reactions catalyzed by enzymes located in,

#Question id: 10251

#Unit 6. System Physiology – Plant

Initial phase of glycolysis, substrates from different sources are channeled into triose phosphate. For each molecule of sucrose that is metabolized, four molecules of triose phosphate are formed. This process how much requires ATP input?