Water absorption in plants is determined by both external environmental conditions and internal plant characteristics. Absorption mainly occurs through osmosis at the root hairs and is conducted throughout the plant via the xylem, with several factors influencing the process:
External (Environmental) Factors:
1. Soil Water Content: Increased soil moisture availability significantly boosts water absorption.
2. Temperature: Higher temperatures enhance transpiration, subsequently increasing water uptake.
3. Soil Aeration: Inadequate aeration restricts the necessary oxygen for root respiration, reducing water absorption.
4. Soil Salinity: Higher salinity levels lower the water potential, thus decreasing water absorption.
Internal (Plant) Factors:
1. Root Surface Area: Larger root hair density increases the efficiency of water absorption.
2. Transpiration Rate: Higher transpiration rates enhance the gradient for water absorption.
3. Metabolic Activity: Increased metabolic activity in root cells promotes water uptake through energy-consuming processes.
Identify the labelled parts P, Q, R, and S in the stages of a dicot embryo shown in the diagram.
Choose the option that indicates correct labelling of 'P', 'Q', 'R', and 'S' of embryo in different stages of its development.
Explain the construction of a spherical wavefront by using Huygens' principle.
The slope of the tangent to the curve \( x = \sin\theta \) and \( y = \cos 2\theta \) at \( \theta = \frac{\pi}{6} \) is ___________.