Transport of Water in Plants

What is a transport system in organisms?

A system that supplies cells with nutrients and removes wastes.

What is the plant vascular system also called?

The vascular system.

What is the function of the plant vascular system?

To transport water, minerals, and sugars around the plant.

What is xylem?

A tissue made of long, dead, hollow tubes that transport water and minerals.

What is the structure of xylem vessels?

Long cells joined end-to-end forming continuous hollow tubes.

Why are xylem cells dead when mature?

To form hollow tubes for efficient water transport.

What strengthens xylem vessels?

Lignin in spiral thickening patterns.

What is the function of lignin in xylem?

It strengthens and supports the vessel walls.

What is phloem?

A transport tissue that moves sugars around the plant.

What are the two main cell types in phloem?

Sieve tube elements and companion cells.

What are sieve tube elements?

Living cells arranged end-to-end that transport sugars through sieve plates.

What are sieve plates?

Perforated cell walls that allow sap to flow between sieve tube cells.

Do sieve tube elements have a nucleus?

No

What is the role of companion cells?

To support sieve tube cells and keep them alive.

What is cambium tissue?

A tissue that produces new xylem and phloem cells.

What are vascular bundles?

Structures made of xylem, phloem, and cambium arranged together.

How are vascular bundles arranged in plants?

As a network throughout the plant.

What is the main role of xylem?

Transport of water and mineral ions from roots to leaves.

What is the main role of phloem?

Transport of sugars (products of photosynthesis).

What is transpiration?

The evaporation of water from leaves through stomata.

What is the transpiration-cohesion-tension theory about?

How water moves through plants from roots to leaves.

How does water enter the roots?

By osmosis.

What is root pressure?

The pressure created as water enters roots by osmosis, pushing water upward.

What is adhesion in water transport?

Water sticking to xylem vessel walls.

What is cohesion in water transport?

Water molecules sticking to each other.

What is capillary action in plants?

Movement of water up xylem due to adhesion and cohesion.

How much water absorbed by roots is lost in transpiration?

About 99%.

Why does transpiration help water movement?

It creates a pull that draws water up the xylem.

How are mineral ions transported in plants?

Dissolved in water, often actively transported into roots.

What is different about mineral ion uptake compared to water?

Mineral ions often require energy (active transport).