NEET Botany

Guttation occurs when root pressure forces water out through hydathodes (water pores) as liquid water droplets, typically at night.

Grana are stacks of thylakoids arranged vertically, while stroma lamellae are unstacked thylakoids connecting different grana.

Q10 of 2.0-3.0 indicates that enzyme activity doubles or triples with every 10°C increase in temperature, typical for biological systems.

RuBisCO is the most abundant enzyme on Earth and catalyzes the carboxylation of RuBP with CO2 in the dark reactions.

Water photolysis (photosystem II) occurs in the thylakoid lumen where oxygen is released as a byproduct.

In darkness, photosynthesis stops, but aerobic respiration continues, consuming O2 and releasing CO2, resulting in measurable gas exchange.

ABA accumulates in guard cells during water stress and causes stomatal closure by reducing turgor pressure in guard cells.

In C4 plants, CO2 first combines with PEP (3-carbon molecule) to form oxaloacetate (4-carbon), which is why it's called C4 photosynthesis.

Soil pH has minimal direct effect on transpiration rate. Primary factors affecting transpiration are light, humidity, temperature, and wind velocity.

Chlorophyll a is the primary pigment that directly participates in the photochemical reactions of both PSI and PSII, while other pigments act as accessory pigments.