In a plant cell, the turgor pressure is maintained mainly by the:
A. Central vacuole
B. Plasma membrane
C. Chloroplast
D. Cell wall
Answer: Option A
Solution (By JKExamLibrary)
The central vacuole occupies a large volume of a mature plant cell and stores water, creating turgor pressure against the cell wall, which maintains cell rigidity and plant structure. The cell wall provides mechanical support but turgor pressure generated by the vacuole is essential for maintaining turgidity, especially in herbaceous plants.
Explanation:
Skeletal muscle, attached to bones, is striated and under conscious (voluntary) control. Smooth and cardiac muscles are involuntary. Skeletal muscles are responsible for locomotion and posture.
Explanation:
Water moves from the soil (high water potential) into root hair cells (lower water potential due to solutes) by osmosis across the semipermeable membrane. Active transport is for minerals, transpiration pull is for upward movement.
Explanation:
Osmosis is the special case of diffusion of water across a semipermeable membrane down its concentration gradient (from high to low water potential). It does not require energy. Diffusion refers to solute movement, active transport requires energy against a gradient, and plasmolysis is the shrinking of protoplasm due to water loss.
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