Plant Structure Flashcards

All 8 cards in this deck

How is the shape of a root hair cell adapted for absorbing water and mineral ions?

A long, narrow extension gives a large surface area, and the thin cell wall gives a short distance for water and ions to cross.

Why do root hair cells contain many mitochondria?

To release energy by respiration for the active transport of mineral ions into the cell.

By which processes does a root hair cell take in (a) water and (b) mineral ions from the soil?

(a) Water by osmosis, down a concentration gradient. (b) Mineral ions by active transport, against the concentration gradient, using energy from respiration.

True or false? Root hair cells contain chloroplasts so they can photosynthesise.

False. Root hair cells have no chloroplasts, because roots are underground and receive no light.

Give three features of the structure of a xylem vessel.

Thick walls strengthened with lignin; dead cells with no cytoplasm; no end walls, forming continuous hollow tubes.

Give two features of phloem tissue that suit it to transporting sucrose.

Living cells with sieve plates (pores in the end walls) for sap to pass through, and companion cells with many mitochondria to supply energy.

True or false? Xylem carries sucrose from the leaves to the rest of the plant.

False. Xylem carries water and mineral ions from the roots; phloem carries sucrose.

In a micrograph of a plant stem, how can you recognise the xylem vessels?

They appear as hollow tubes with thick lignified walls and no cytoplasm inside.