B3.2 LO 7-10 Transport of Water in Plants

Which of the following processes primarily drives the movement of water from the roots to the leaves in vascular plants?

• Active transport

• Transpiration

• Osmosis

• Diffusion

What is the primary purpose of lignified walls in xylem vessels?

• To allow selective permeability

• To store nutrients

• To withstand tension and mechanical stress

• To facilitate gas exchange

In a transverse section of the stem of a dicotyledonous plant, where are the xylem and phloem typically located?

• The xylem is closer to the epidermis, and the phloem is closer to the center.

• The phloem is closer to the epidermis, and the xylem is closer to the center.

• Both the xylem and phloem are evenly distributed throughout the stem.

• The xylem and phloem are found only in the epidermis.

In a transverse section of the root of a dicotyledonous plant, the vascular bundles are arranged in which structure?

• Epidermis

• Cortex

• Cambium

• Stele

What causes water to be pulled out of xylem vessels and into leaf cells?

• • Positive pressure potential

• • Negative pressure potential

• • Root pressure

• • Active transport

What property of water molecules allows them to form a continuous column in the xylem?

• • Adhesion

• • Capillary action

• • Cohesion

• • Osmosis

Which structure in the leaf is primarily responsible for the loss of water during transpiration?

• •  Epidermis

• • Stomata

• • Mesophyll cells

• • Cuticle

Transpiration creates a tension that draws water up in the xylem. This process is mainly driven by which of the following?

• • Active transport in the roots

• • Evaporation of water from leaf surfaces

• • Diffusion of minerals in the soil

• • Photosynthesis in the leaves

Why do xylem vessels lack cell contents and have incomplete or absent end walls?

• • To store nutrients

• • To allow unimpeded flow of water

• • To enhance photosynthesis

• • To provide structural support

What is the role of lignin in xylem vessels?

• • To conduct photosynthesis

• • To facilitate nutrient uptake

• • To strengthen the walls and withstand tension

• • To store water