Xylem and Phloem Quiz 1

Imagine you’re an early land plant, like moss. What’s the biggest challenge you face if you want to grow taller?

• Finding enough sunlight for photosynthesis.
• Developing stronger roots.
• Transporting water and nutrients throughout the plant.
• Attracting pollinators.

Answer explanation

Early land plants like mosses faced the challenge of transporting water and nutrients throughout their structures, limiting their ability to grow tall.

A small plant absorbs water through its roots. Which process is sufficient to distribute this water to all parts of the plant?

• Osmosis
• Active transport
• Diffusion
• Photosynthesis

Answer explanation

In small plants, diffusion is sufficient to distribute water and nutrients because the plant's structure is small, allowing easy distribution without the need for a complex transport system.

Why did the evolution of vascular tissues allow plants to grow taller?

• They provided structural support to the plants.
• They enabled efficient transport of water and nutrients.
• They improved photosynthesis efficiency.
• They protected plants from herbivores.

Answer explanation

The evolution of vascular tissues allowed plants to grow taller by enabling the efficient transport of water, minerals, and food throughout the plant, overcoming the limitations of diffusion.

If a plant did not develop vascular tissues, what would likely happen as it attempts to grow taller?

• It would still grow tall, relying on diffusion.
• It would struggle to distribute nutrients and remain small.
• It would develop stronger leaves to capture more sunlight.
• It would increase its photosynthetic rate to compensate.

Answer explanation

Without vascular tissues, a plant would struggle to distribute nutrients and water effectively, limiting its growth to remain small.

Which statement best describes the function of xylem in a plant?

• Xylem transports food from the leaves to the roots.
• Xylem transports water and dissolved minerals from the roots to the leaves.
• Xylem stores energy for the plant.
• Xylem protects the plant from pathogens.

Answer explanation

Xylem is responsible for transporting water and dissolved minerals from the roots to the leaves, a unidirectional transport system.

A plant needs to transport sugars to its roots for storage. Which vascular tissue is responsible for this?

• Xylem
• Phloem
• Stomata
• Cortex

Answer explanation

Phloem is responsible for transporting food, primarily sugars, to various parts of the plant, including down to the roots for storage.

Why do plants have separate xylem and phloem tissues?

• To prevent food and water from mixing during transport.
• To speed up the growth process.
• To increase the plant’s resistance to disease.
• To store different types of nutrients.

Answer explanation

Plants have separate xylem and phloem tissues to ensure that water and food are transported separately and efficiently, preventing them from mixing.

What would happen if phloem only transported food in one direction, like xylem?

• Leaves would not receive enough water.
• Roots would lack the necessary sugars for energy.
• The plant would grow faster.
• There would be no effect on the plant.

Answer explanation

If phloem only transported food in one direction, roots would not receive the necessary sugars needed for energy, impacting the plant’s overall health and growth.

During photosynthesis, where is the food primarily produced in a plant?

• Roots
• Stem
• Leaves
• Flowers

Answer explanation

Food, primarily sugars, is produced in the leaves during photosynthesis as they contain chloroplasts that capture sunlight.

How does the structure of xylem tissue aid in its function?

• Its flexible walls allow easy movement of food particles.
• Its wide and hollow structure allows efficient water transport.
• Its dense structure supports the plant’s weight.
• Its small size facilitates rapid diffusion of nutrients.

Answer explanation

The wide and hollow structure of xylem tissues allows efficient upward transport of water and dissolved minerals.