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

Which of the following supports the hypothesis that viceroys receive protection from predation because they resemble monarchs?

#Question id: 10205

#Unit 6. System Physiology – Plant

The xanthophyll cycle, which comprises the three carotenoids violaxanthin, antheraxanthin, and zeaxanthin, establishes an ability to dissipate excess light energy in the leaf, Under high light the conversion of the carotenoids such as

#Question id: 10206

#Unit 6. System Physiology – Plant

The excess energy is absorbed by three carotenoids molecules such as violaxanthin, antheraxanthin, and zeaxanthin, which of the following statements correct about these molecules?

#Question id: 10207

#Unit 6. System Physiology – Plant

In high light, violaxanthin is converted into zeaxanthin, via the intermediate antheraxanthin by the enzyme known as

#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