Transcript Tissues Vascular Plant Body

Chapter 25
Plant Structure and Function
Section 1: The Vascular Plant Body
Section 2: Transport in Plants
Section 1
The Vascular Plant Body
Objectives:
•Identify the three kinds of tissues in a vascular
plant's body, and state the function of each.
•Compare the structures of different types of roots,
stems, and leaves.
•Relate the structures of roots, stems, and leaves to
their functions.
Section 1
The Vascular Plant Body
Tissues
•Vascular Plant Body A vascular plant’s body
contains three kinds of tissues—dermal tissue,
ground tissue, and vascular tissue.
•Dermal Tissue Dermal tissue covers a plant. A thin
layer of epidermis covers nonwoody parts. Several
layers of cork cover woody parts.
•Ground Tissue Ground tissue is specialized for
photosynthesis in leaves and for storage and support
in stems and roots.
Section 1
The Vascular Plant Body
Vascular Tissues
•Vascular Tissues Vascular tissue conducts water,
minerals, and organic compounds throughout the
plant.
•Xylem Xylem contains vessels, which are made up
of cells that conduct water only after they lose their
cytoplasm. Water flows between cells through pits
and perforations in their cell walls.
•Phloem Phloem contains sieve tubes, which are
made up of cells that are still living. Substances pass
between the cells through pores.
Section 1
The Vascular Plant Body
Roots
•Roots Roots have a central core of vascular tissue
that is surrounded by ground tissue and epidermal
tissue. Root hairs on root tips increase the surface
area available for absorption.
Section 1
The Vascular Plant Body
Stems
•Nonwoody Stems Nonwoody stems contains
bundles of xylem and phloem embedded in ground
tissue.
•Woody Stems Woody stems have an inner core of
xylem surrounded by a cylinder of phloem.
Section 1
The Vascular Plant Body
Leaves
•Leaves Leaves are a mass of ground tissue and
vascular tissue covered by epidermis. The ground
tissue cells conduct photosynthesis. Gases are
exchanged through the stomata in the epidermis.
Section 2
Transport in Plants
Objectives:
•Relate transpiration to the movement of water up a
plant.
•Describe how guard cells regulate the rate of
transpiration.
•Recognize several distinguishing features of sugar
maple trees.
•Describe the process of translocation in a plant.
Section 2
Transport in Plants
Movement of Water
•Transpiration Transpiration, the loss of water from
a plant’s leaves, creates a pull that draws water up
through xylem from roots to leaves.
•Guard Cells and Transpiration Guard cells control
water loss by closing a plant’s stomata when water is
scarce. Thus, they also regulate the rate of
transpiration.
Section 2
Transport in Plants
Movement of Organic Compounds
•Translocation Organic compounds are pushed
through the phloem from a source to a sink in a
process called translocation.