Transport in Plants

These flashcards cover key concepts related to plant transport mechanisms, including water movement, the role of cells and ions in stoma function, and the basic principles of diffusion and osmosis.

How does water get to the top of a tree?

Water is pulled up by negative pressure in the xylem.

What causes the movement of water, minerals, and sugars in most vascular plants?

Water and minerals are pulled up by negative pressure; sugars are pushed by positive pressure.

What is the water potential equation?

Ψtotal = Ψs (solute) + Ψp (pressure).

What happens to a plant cell in a hypotonic solution?

The cell gains water, swells, and may lyse (burst).

What is the role of aquaporins in plant cells?

Aquaporins are transport proteins that facilitate the diffusion of water across cell membranes.

How do guard cells regulate stomatal opening?

Guard cells accumulate K+ ions, increasing turgor pressure and causing stomata to open.

What is the difference between passive and active transport?

Passive transport moves molecules along the concentration gradient without energy; active transport moves molecules against the gradient using ATP.

What process drives the bulk flow of water in the phloem?

Bulk flow of sugars is driven by positive pressure as sugars are pushed towards sinks.

What does it mean if a solution is hypertonic?

A hypertonic solution has a greater solute concentration than that inside the cell, leading to water moving out of the cell.

What is turgor pressure?

Turgor pressure is the pressure exerted by the cell wall against the water-filled vacuole of a plant cell, helping maintain its shape.

What is condensation?

Condensation is the process by which water vapor in the air cools and changes into liquid water, often forming clouds.