Refer to the following experiment, which is designed to test the co evolutionary relationships among an unpalatable butterfly (the  monarch),  a  palatable  butterfly  (the  viceroy),  and  a  butterfly  predator  (the  jay).  Monarch butterflies are reared on three diets: milkweed (their natural food), cabbage, and cabbage treated with an extract from milkweed leaves. Viceroy butterflies, mimics of monarchs, also are reared on three diets: willows (their natural food), cabbage, and cabbage treated with an extract from milkweed leaves. In trial 1 of the first experiment, adult butterflies reared on a particular diet are presented one at a  time  at  1-hour  intervals  to  jays  and  the  jays  are  allowed  to  feed.  Each jay is  fed  until  it refuses to eat the butterfly presented, but no more than 12 butterflies are presented to a jay during a particular test. Five birds are used for each test; therefore, up to 60 butterflies can be consumed for each diet test. The observer records the actual number of butterflies  eaten. In trial 2, the experiment is repeated 2 weeks later. In the second experiment, the butterflies are reared on the same diets as in experiment 1. However, when they are offered to jays, some jays receive a monarch  reared  on  milkweed  before  being  offered  the  butterflies  reared  on  the  experimental  diets;  the  other  group  of jays is  first given a viceroy reared on willow before being  offered the butterflies reared on the experimental diets. The initial butterfly offered is included in the total number eaten, but no more than 12 butterflies are presented to each jay.

The experimental design and the data indicate which of the following about the jays? 

#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: 9591

#Unit 6. System Physiology – Plant

In light reaction, the funneling of excitation from the antenna system toward the reaction centre has been shown,

a.) The excited-state energy of pigments increases with distance from the reaction centre; that is, pigments closer to the reaction centre are lower in energy than those farther from the reaction centre

b.) The energy gradient ensures that excitation transfer toward the reaction centre is energetically favorable and that excitation transfer back out to the peripheral portions of the antenna is energetically unfavourable

c.) Some energy is lost as heat to the environment by this process, but under optimal conditions almost all the excitation energy absorbed in the antenna complexes can be delivered to the reaction centre

d.) The excited-state energy of  pigments decreases with distance from the reaction centre

Which of the following above combination is true?

#Question id: 9587

#Unit 6. System Physiology – Plant

The structure of the four major protein complexes in the thylakoid membrane are organised form such as ;

a.) PSII is located predominantly in the stacked regions of the thylakoid membrane and Cytochrome b6f complexes are evenly distributed

b.) PSI and ATP synthase are found in the unstacked regions protruding into the stroma

c.) Lateral separation of the two photosystems requires that electrons and protons produced by PSII be transported directly to PSI and the ATP coupling enzyme

d.) Four main protein complexes of the thylakoid membrane, shown also are the two diffusible electron carriers—plastocyanin, which is located in the thylakoid lumen, and plastohydroquinone (PQH2) in the membrane, The lumen has a positive electrical charge with respect to the stroma

Which of the following statements correct?

#Question id: 9582

#Unit 6. System Physiology – Plant

Electrons ejected from chlorophyll travel through a series of electron carriers organized in the “Z Scheme” shows a current version of the Z scheme, in which all the electron carriers known to function in electron flow from H2O to NADP Presented in the following sequence;

a.) P680 reduce by Yz has received electrons from oxidation of water P680→P680*→pheophytin→ plastoquinones→ cytochrome b6 f complex→ plastocyanin→ in turn reduces (PSI) P700+

b.) P700+→ P700*→ membrane-bound iron–sulfur proteins → A0→ A1 → flavoprotein ferredoxin–NADP reductase (FNR) soluble → ferredoxin(Fd) → NADP+ to NADPH

c.) P700+→ P700*→ A0→ A1→ membrane-bound iron–sulfur proteins→ ferredoxin(Fd)→ soluble flavoprotein ferredoxin–NADP reductase (FNR)→ NADP+ to NADPH

d.) P680 reduce by Yz has received electrons from oxidation of water P680→P680*→ plastoquinones → pheophytin → cytochrome b6 f complex→ plastocyanin→ in turn reduces (PSI) P700+

Which one of the following combinations is correct?

#Question id: 9581

#Unit 6. System Physiology – Plant

These four Photosystem II, Cytochrome b6 f, Photosystem I and ATP synthase integral membrane complexes are vectorially oriented in the thylakoid membrane to function as follows, find out the incorrect statements;

#Question id: 9284

#Unit 6. System Physiology – Plant

Following are some facts regarding spatial separation of PSI and PSII. Which one would be INCORRECT?