Match the following columns:

Column I	Column II
a. Enhancement effect	1. Warburg
b. C3 cycle	2. Hatch and slack
c. C4 cycle	3. Emerson
d. Two step photosynthesis	4. Calvin

Solution (By Examveda Team)

a. Enhancement effect is given by Emerson- The Emerson effect is the increase in the rate of photosynthesis after chloroplasts are exposed to the light of wavelength 680 nm (deep red spectrum) and more than 680 nm (far red spectrum).
b. C₃ cycle is given by Calvin- The Calvin cycle, light-independent reactions, of photosynthesis is a series of chemical reactions that convert carbon dioxide and hydrogen-carrier compounds into glucose.
c. C₄ cycle is given by hatch and slack- C₄ carbon fixation or the Hatch–Slack pathway is one of three known photosynthetic processes of carbon fixation in plants. It owes the name to the 1960's discovery by Marshall Davidson Hatch and Charles Roger Slack that some plants when supplied with ¹⁴CO₂, incorporate the ¹⁴C label into four-carbon molecules first.
d. Two-step photosynthesis is given by Warburg- The Warburg effect is the decrease in the rate of photosynthesis due to high oxygen concentrations. Oxygen is a competitive inhibitor of carbon dioxide fixation by RuBisCO which initiates photosynthesis. Furthermore, oxygen stimulates photorespiration which reduces photosynthetic output. These two mechanisms working together are responsible for the Warburg effect.