AICE Biology Chapter 7

What is the primary process through which plants produce their own nutrients?

Photosynthesis.

How do plants absorb water and minerals from the soil?

Through their roots.

What structures in plants are primarily responsible for photosynthesis?

Leaves.

Where do roots typically extend to in order to access essential nutrients?

Deep underground.

What essential materials do plants need to transport throughout their structures?

Water, minerals, and nutrients.

What is the role of xylem in plants?

To transport water and mineral ions from roots to aerial parts.

What type of flow is exhibited by xylem?

One-way flow (primarily upward).

What is the role of phloem in plants?

To carry sugars and nutrients from leaves to various parts of the plant.

What type of flow does phloem exhibit?

Two-way flow (upward or downward).

What are the main components of a plant's vascular system?

Xylem and phloem.

What is the term used for the system of fluid-filled tubes in plants?

Vascular system.

What features allow xylem vessels to effectively transport water?

Dead, hollow cells reinforced with lignin.

What tissue is responsible for the transport of sugars in plants?

Phloem.

What is the process of losing water vapor from plant leaves called?

Transpiration.

How does transpiration affect water movement in plants?

It creates a water potential gradient that pulls water from roots to leaves.

What is the main function of root hairs?

To increase the surface area for water absorption.

Which pathway allows water to move through living cells?

Symplast pathway.

Which pathway allows water to move through cell walls?

Apoplast pathway.

What role does the Casparian Strip play in root structure?

It acts as a waterproof barrier controlling the entry of substances into the vascular system.

What are xerophytes?

Plants specially adapted to thrive in dry environments.

What adaptations do xerophytes have to minimize water loss?

Thick cuticle, sunken stomata, and hairy leaves.

What are assimilates in the context of plant transport?

Organic compounds created through assimilation processes.

What is the difference between the source and sink in plant transport?

Source is where assimilates are produced, and sink is where they are consumed or stored.

What cells form the sieve tubes in phloem?

Sieve tube elements.

What is the function of companion cells in the phloem?

To support sieve tubes with metabolic activity.

What hypothesis explains the movement of phloem sap?

Mass flow hypothesis.

How is sucrose loaded into phloem sieve tubes?

By active transport into the sieve tube.

What happens to water when sucrose is loaded into phloem?

Water enters by osmosis, raising hydrostatic pressure.

How does sap move in phloem?

From areas of high pressure (source) to low pressure (sink).

What is a vascular bundle?

A strand of vascular tissue present in plants.

What is parenchyma tissue in plants?

The basic packing tissue that aids in food storage and transport.

What is collenchyma tissue?

A strengthening tissue with thicker walls, providing support in plants.

What is sclerenchyma tissue?

Thick-walled cells that provide support and strength in plants.

What material is important for strengthening xylem and sclerenchyma?

Lignin.

How does water move from the soil into the roots?

By osmosis through root hairs.

What is xylem sap?

The fluid that is transported in xylem vessels.

What is phloem sap?

The fluid within sieve tubes, containing substances such as sucrose and amino acids.

Which type of plant has broad leaves with a stalk?

Dicotyledons.

What type of plant exhibits long, narrow leaves?

Monocotyledons.

What are the primary transport organs in plants?

Stems, roots, and leaves.

What is the definition of transpiration in plants?

Loss of water vapor from plant surfaces through stomata.

What role do stomata play in plants?

They facilitate gas exchange and water loss.

What is the main driving force behind water transport in plants?

Transpiration creating a water potential gradient.

What protects the vascular tissue in roots?

Endodermis.

What is the main function of mesophyll in leaves?

Responsible for gas exchange and photosynthesis.

How are nutrients transported in phloem?

Via mass flow driven by pressure differences.

What defines the mass flow hypothesis?

Movement of phloem sap driven by differences in hydrostatic pressure.

What structure supports the design of sieve tubes?

Sieve plates enable the flow of sap.

Why is water movement in xylem considered passive?

It requires no energy expenditure.

What creates the upward force in water transport through plants?

Transpirational pull.

What characteristic of xylem cells aids in efficient water transport?

They are dead, hollow cells joined end to end.

How is the structure of phloem different from that of xylem?

Phloem has living cells and is bidirectional in transport.