Emerson's enhancement effect and red drop have been instrumental in the discovery of
1. two photosystems operating simultaneously
2. photophosphorylation and cyclic electron transport
3. Oxidative phosphorylation
4. photophosphorylation and non-cyclic electron transport

In a chloroplast the highest number of protons are found in

The oxygen evolved during photosynthesis comes from water molecules. Which one of the following pairs of elements are involved in this reaction?
1. Manganese and chlorine
2. Manganese and potassium
3. Manganese and molybdenum
4. Manganese and calcium

In photosynthesis, the light-independent reactions take place at

The structures that are formed by stacking of organised flattened membranous sacs in the chloroplasts are

Anoxygenic photosynthesis is characteristic of
1. Rhodospirillum
2. Spirogyra
3. Chlamydomonas
4. Ulva

The correct sequence of cell organelles during photorespiration is
1. chloroplast-golgi bodies-mitochondria
2. chloroplast-rough endoplasmic reticulum-dictyosomes
3. chloroplast-peroxisome-mitochondria
4. chloroplast-vacuole-peroxisome

PGA, as the first ${\mathrm{CO}}_2$ fixation product, was discovered in photosynthesis of
1. bryophyte
2. gymnosperm
3. angiosperm
4. alga

${\mathrm{C}}_4$ -plants are photosynthetically more efficient than ${\mathrm{C}}_3$ -plants because
1. ${\mathrm{CO}}_2$ compensation point is more.
2. ${\mathrm{CO}}_2$ generated during photorespiration is trapped and recycled through PEP carboxylase.
3. ${\mathrm{CO}}_2$ efflux is not prevented.
4. they have more chloroplasts.

In the leaves of ${\mathrm{C}}_4$ -plants, malic acid synthesis during ${\mathrm{CO}}_2$ fixation occurs in
1. epidermal cells
2. mesophyll cells
3. bundle sheath
4. guard cells