Systemic Transport in Flowering Plants

The vascular system of the flowering plants functions like which human system?

Circulatory system

Every cell in the flowering plant body is near to, and can exchange chemicals with, the —

Vascular system

What does the Xylem tissue do?

Transports the absorbed materials from root to shoot (aerial organs)

What are root hairs specialized for?

Absorption

What must deliver water to leaves?

Xylem tissue

___ is a reactant (substrate) for photosynthesis.

H2O

Which tissue enables the flowering plant to transport the substances that its roots absorb from the soil to all its cells?

Xylem tissue

In flowering plants, which vascular tissue also provides each plant with its primary source of structural support?

Xylem tissue

What is the most common molecule and the most critical nutrient in the Xylem sap?

Water (H2O)

Why must the Xylem tissue deliver water (H2O) molecules to the leaves of the plant?

• H2O is a ___ (___) for photosynthesis

• H20 accumulation increases the ___ ___ (“swollen) pressure of each leave to —

  • Increase leaf ___ ___ to intercept more sunlight

  • Provide leaves with ___ support.

• H2O is a reactant (substrate) for photosynthesis

• H20 accumulation increases the internal turgor (“swollen) pressure of each leave to —

  • Increase leaf surface area to intercept more sunlight

  • Provide leaves with structural support.

Which process drives the ascent of the xylem sap upwards in the xylem tissue?

Transpiration

Plants must reduce leaf temperature to maintain photosynthesis and all other metabolic processes to occur in the leaf, they achieve this through —

Transpiration

Xylem tissue consists of…

Many cell types

Which two cell types in xylem tissue are specialized for transport?

Tracheids and vessel elements

The Xylem sap moves through the hollow interior of two cell types that are like “pipes”. What are these cell types?

Tracheid and vessel element

Which cell types in xylem tissue provides structural support for xylem tissue and consequently for the entire plant?

• Tracheid

• Vessel Element

• Sclerenchyma Cell (Fiber)

___ tissue (bark) delivers ___ sap in many directions to ensure all cells have ___.

Phloem tissue (bark) delivers phloem sap in many directions to ensure all cells have sucrose.

What is the composition of the phloem sap composition?

• ___ molecules

• Electrical signals ___

  • Enables rapid ___

• ___ ions

  • Ammonium, Calcium, Copper, Iron, Magnesium, Manganese, Nitrate, Phosphate, Potassium, Sodium, Sulfate, etc.

• ___ molecules.

  • Hormones, proteins, RNA

• ___ (90% of dray matter)

  • Amino acids (less than 1%)

  • Fatty acids (less than 1%)

• ___ containing molecules

Which tissue enables the flowering plant to transport the carbohydrates made in the leaf cells by photosynthesis to all the cells in its body?

Phloem Tissue

Phloem tissue transports sucrose from source tissue with high sucrose concentration to…

Sink tissues with lower sucrose levels

What is an example of a source tissue in the flowering plant that provides sucrose to the sink tissues with low sucrose concentration?

Photosynthetic leaf

What is the most common food molecule in the phloem sap?

Sucrose

The phloem sap moves through the interior of a cell type specialized for transport. What is this cell type?

Sieve Tube Element

Which cell type in the Phloem tissue is specialized to provide structural support?

Sclerenchyma Cell (Fiber)

What enables the cytosol of adjacent plant cells to exchange hormones to permit cell to cell communication and consequently coordinate their activities?

Plasmodesmata

What enables some plant viruses to move from an infected plant cell to an adjacent uninfected plant cell?

Plasmodesmata

What two tissues does the vascular system consist of?

Xylem tissue and Phloem tissue

All living plants are near the vascular system to facilitate…

materials exchange

The vascular system connects all the body’s…

cells

All cells in flowering plants require ___.

carbohydrates

What is the function of carbohydrates in flowering plants?

• Enable ATP synthesis

• Provide carbon skeletons

What is the main source of structural support for woody plants?

Xylem (Wood)

What are the two essential functions of transpiration?

• Creates the negative pressure (“transpirational pull”) that drives the ascent of xylem sap

• Regulates leaf temperature to maintain efficient metabolism

Why are tracheid and vessel elements hollow at maturity?

The hollowness enables efficient transport

Which cell type provides structural support in both xylem tissue and phloem tissue?

Sclerenchyma cells

How are the ends of stacked sieve tube elements specialized to permit the direct cell to cell transport of phloem sap?

Their porous ends (sieve plates) enable movement between stacked sieve tube elements

Do companion cells provide metabolic support to sieve tube elements in the phloem sap?

YES! Companion cells provide ATP, proteins, and signaling molecules

Which process enables rapid distribution of materials within larger plant cells?

Cytoplasmic streaming

Which protein filaments, motor proteins, and energy source does cytoplasmic streaming require?

• Actin filament (microfilament) and myosin protein interaction

• ATP (energize myosin motor proteins)