Transcript Roots, Stems, Leaves and Tissues 09

Roots, Stems, Leaves and Tissues
Tissue Systems
• Plants consist of four different types of tissues
• Meristematic tissue is located at the tips of shoots
and roots and is responsible for the growth that
takes place in a plant’s lifetime
• Meristematic tissue is the only tissue that produces
new cells by mitosis and is found at the tips
• Apical Meristems are a group of cells that
reproduce at the tips of roots by mitosis, causing
elongation of the root
Tissues, cont.
• Dermal Tissue- the outer covering of a plant
is known as dermal tissue and usually
consists of a single layer of epidermal cells
• Vascular Tissue- tissue that carries food,
water and minerals throughout the plant.
– Made of many different types of cells
– Allows transport of materials to defy gravity
More Tissues
• Ground tissue- the “meat” of the plant- the
area between dermal and vascular tissue
• Consists of three different types of cells
Roots
• Roots take in water and nutrients, anchor
the plant in the ground and hold the plant
upright
• Taproots and fibrous roots are the two
main types
• Roots have a complex structure and allow
the plant to transport materials easily
Root Types
taproot
Fibrous
root
Stems
• Stems produce leaves,
branches and flowers
• They hold the leaves
up in the sunlight
• They also allow for
transport of materials
between roots and
leaves
Leaves
• The structure of leaves are optimized for
absorption of sunlight
• Photosynthesis- the bulk of leaves is made of a
specialized ground tissue called mesophyll which
is packed with chloroplasts
• Transpiration- is the loss of water through the leaf
• Gas exchange- carbon dioxide and oxygen are
exchanged through the leaf’s surface
Flowers
• Flowers are the reproductive structure of
flowering plants, also known as
Anthophytes or Angiosperms
• Flowers come in many shapes, colors and
sizes, depending on the genetic make-up of
the species
• Flowers can turn into fruits once pollinated,
which protect the seeds of the plant and aid
in dispersal
Flower Organs
• Sepals protect the flower
• Petals can be brightly colored and attract
pollinators and provide them with a landing
pattern
• Stamens- Male reproductive part of the
flowers, consists of the filament and the
anther, produces pollen
• Female reproductive part is the pistil, it
consists of stigma, style and the ovary
Flower Structure
Sepal
Pages to help 222, 644-646