Plant pathways
A plant needs to transport water and nutrients from its roots to its leaves, and
needs to transport the glucose it produces out from the leaves to the cells that
need food. This requires a transport system and a set of pathways along which
it can occur.
There are two types of tubes that transport food and water inside and around
plants—xylem and phloem. Phloem and xylem are complex tissues that
perform transportation of food and water in a plant. They are the vascular
tissues of the plant and together form vascular bundles. They work together as
a unit to bring about effective transportation of food, nutrients, minerals and
water.
Xylem tubing can be found in roots, stems and leaves. The function Xylem
tubes carry water and minerals (e.g. phosphorous, potassium, nitrogen, sulfur,
calcium, iron and magnesium) from the soil, up into the stems and leaves.
Xylem tubes are made of dead cells with a woody substance whichgives
mechanical strength to plant. Unlike animals, a plant does not have a heart to
pump liquid through its tubes. Instead, water is pushed upwards by pressure in
the roots. Evaporation through the stomata (i.e. tiny holes in the leaves)
assists further in sucking the water upwards.
Phloem tubes are made from living cells. Their function is to transport the
glucose that is produced by photosynthesis in the leaves to where it is needed.
This movement of substances is called translocation. Plants use the glucose
they make in four different ways. Some of the glucose will be:
 used immediately to provide the plant with energy
 stored in the plant’s leaves, stems, roots, seeds and fruits for later use,
such as the production of buds in spring
 used to make cellulose to reinforce the cell wall
 combined with minerals to make proteins needed for the plant to
grow.
Plant Pathways (Answers)
3 Level True/False: Read the information below and answer the following questions.
Statements
T/F What did you read that told you this?
Locate Facts- Read the whole text and locate underlined words to see it it’s true or false.
Xylem is made of dead cells.
T
Infer Meaning- Read this and decide if it’s true of false according to the ideas presented.
Phloem vessels are involved in the
movement of water through a plant from
it’s roots to its leaves.
Apply/ Think about ideas- Think about this statement and decide, based on the whole reading, if
you think it’s true/false. Include pieces of text that helped you decide.
Xylem vessels are involved in the movement of water through a plant from it’s roots to its
leaves.
Traspiration explains how water moves up the plant against gravity in tubes made of dead
xylem cells.
Water evaporates and diffuses out of the leaf. This is called transpiration.
Xylem is made of dead cells.
Phloem is made of living cells
Phloem is the living tissue that carries nutrients in all directions in a plant to growing tissue and
strage organs..
Phloem tissue are involved in translocation.
Translocation is the movement of substances from the stems to growing tissue and storage
tissue through out the plant.
Water is absorbed from the soil through the root cells and then travels up to the leaves through
xylem vessels.
Water evaporates from the leaves through the process of transpiration.
Xylem cells act like a drinking straw, producing a flow of water and dissolved minerals from
roots to leaves.
Plants need living phloem in order to transport sugars.
Xylem is found in the roots only (T or F)