Concept explainers
To review:
The coupling reactions involved in the emission of light in the fireflies by redrawing the given diagram.
Introduction:
The fireflies emit energy in the form of light and this phenomenon is known as bioluminescence. The light is emitted from an organ known as the firefly lantern, which is located in their abdomen. This is a form of mating signal through which the fireflies attract mates of the opposite sex.
During the generation of light by the luciferin in the firefly, an intermediate gets formed at the site of the luciferase enzyme. This complex consists of luciferin covalently bonded to adenosine monophosphate (AMP). This complex or intermediate further reacts with oxygen to give rise to oxidized form of luciferin, which ultimately emits light. These steps are shown in the figure as follows:
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LIFE:SCIENCE OF BIOL.(LL) >CUSTOM<
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- As you might suspect, B-carotene, C,Hw precursor to vitamin A, was first isolated from carrots. Dilute solutions of B-carotene are yellow, hence its use as a food coloring. In plants, it is almost always present in combination with chlorophyll to assist in the harvesting of the energy of sunlight and to protect the plant against reactive species produced in photo- synthesis. As tree leaves die in the fall, the green of their chlorophyll molecules is replaced by the yellows and reds of carotene and carotene-related molecules. Compare the carbon skeletons of B-carotene and lycopene. What are the similarities? What are the differences? H3C. H3C CH3 CH3 CH3 H,C CH3 CH3 CH3 B-Carotenearrow_forwardConsider the reaction catalyzed by PFK. In the presence of ATP, which of the following will be expected? Select all that apply. The T-state is stabilized The rate of the reaction is enhanced. The initial velocity plot would show a shift in the curve to the right The quaternary structure of PFK is stabilized to promote efficient binding of substratearrow_forwardWhat type of inhibition is observed from the shift of the Lineweaver-Burke plot ahown in the graph below where the solid Ine represents the uninhibited enzymatic reaction while the broken line represents the inhibited enzymatic reaction? A. Irreveraible inhíbítion B. Noncompetitive inhíbition C. Competitive inhíbition D. Uncompetitive inhibition Potassium cyanide ia a polson which combines with cytochrome A3 to prevent binding of oxygen to the enzyme without altering the Km of the reaction with respect to reduced cytochrome c. Which type of inhibition does this represent? A. Irreveraible inhibition c. Competitive inhibition D. Uncompetitive inhibition B. Noncompetitive inhibition _10. Which of the following enzyme classes catalyze reactions in which two molecules become dissociated from each other? A. Kinase в. Нуdrolase c. Isomerase D. Ligase Which of the following enzyme classes catalyze reactions in which two molecules become covalently linked to each other? A. Kinase B. Hydrolase…arrow_forward