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SECTION 14.1 PLANT ORGANS, TISSUES AND CELLS
Pages 381-390
ROOT AND SHOOT SYSTEMS
Roots are structures that anchor a plant in the soil, absorbing minerals and water and
providing structural support.
Monocots (ANGIOSPERMS)
 Fibrous root system:
a mat of thin roots

Examples:
Grasses, orchids, lilies
Dicots (ANGIOSPERMS)
 Taproot system:
One thick central root with thin branches

Examples:
Dandelions, canola, maple tree
Shoots are above-ground structures consisting of stems, leaves and flowers.
Stems are the parts of a plant that support leaves and flowers.
Nodes are the points on the stem which leaves are attached. Internodes are the portions
of the stem between nodes. Stems play an important role in ____transporting______
materials in a plant. ___Vascular tissue______ runs vertically in the stem and transports
____water and ____minerals___ from the ____roots up to the ___leaves__, and
____food from the ___leaves__________ to other parts of the plant, such as growing
buds, flowers and roots. Undeveloped shoots are called ___buds_______. A
____terminal_________ bud is found at the tip of a stem.
___Axillary____________________ buds are found in the ____angles_______ formed
by a leaf and the main stem. These angles are called ___axils_______. Growth from
axillary buds forms the plant’s ____branches____________.
THE LEAF
Define the following:
Leaves: the primary food manufacturing sites of a plant
Blade: main, usually flattened part of the leaf
Petiole: stalk that connects the leaf blade to the stem
Venation: arrangement of veins on a leaf
The vein that runs through the petiole and into the blade consists of _______vascular
tissue__________________ and ______supportive tissue. These veins carry water and
nutrients into the leaf, and transport sugars from the leaf to other parts of the plant.
Contrast veins in monocots vs. dicots.
Monocots have parallel veins, and dicots have branching veins
FLOWERS AND SEXUAL REPRODUCTION
A flower is a specialized ___shoot__, unique to ____angiosperms__.
Define the following:
Sepals: structures that cover and protect the flower bud and are usually green
Petals: usually colourful, modified leaves that are part of a flower
Stamens: male reproductive structures in flower
Pistils: female reproductive structures in plants
Anther: the part of the stamen that produces pollen
Ovary: plant female reproductive structure containing ovules
Ovule: plant reproductive structures that develop into seeds when fertilized
Style: plant female reproductive structure that supports the stigma
Stigma: sticky tip of the pistil where the pollen lands
Endosperm: nutrient-rich tissue that nourishes the growing seed embryo
SEED DEVELOPMENT AND DISPERSAL
Read page 384-385 and take notes below:
 Parts of seed:
 See Fig. 14.11 a) b), page 384
o Seed coat- tough outer layer to protect embryo and endosperm
o Embryo- baby plant (mini root and shoot)
o Endosperm- food source for developing embryo contains starch,
proteins, and oil
o Cotyledon- embryonic leaf, it stores and transfers nutrients to the
embryo. Monocots have one and dicots have 2.

Seed dispersal
o Animal fur or human clothing (sticking)
o Eaten by animal in fruit, seed gets digested out
o Water (coconuts)
o Wind
SEED GERMINATION
Germination is the process where a plant embryo within a seed begins to grow.
Seeds must soak up water in order to germinate. This will expand the seed and split the
seed coat. Water also triggers metabolic changes in the embryo that enable it to grow.
Look at Figure 14.13, page 386, to compare seed germination of Monocots and Dicots.
VEGETATIVE REPRODUCTION
Many plants are also capable of __asexual reproduction___________. In plants, this is
called vegetative reproduction. The offspring are _____genetically identical____
to the original plant. It can occur naturally or with human help. The simplest way to
clone a plant is to _____cut off______ a __leaf__ or ____stem_____ and place the cut
end in water or soil. The __cells at the cut end of the petiole or stem become
_____undifferentiated_____________________ and then form new ____plant
tissue____________________ and organs. You get a new plant genetically identical to
the original one. In many ___woody__ plants, a ___branch____ from one plant can be
grafted onto the __stem__ of another plant belonging to the same or closely related
species. It is widely used by __fruit growers___________. See Figure 14.15.
MAIN TISSUE SYSTEMS OF A PLANT
See Figure 14.16 for a diagram.
Dermal Tissue is the ____outer covering______ or skin of the plant. The
___epidermis_________, which is the dermal tissue of __non-woody organs_______,
consists of one or more layers of cells. It covers and ___protects_________ all the young
parts of the plant. Some is specialized, leaves and stems can secrete a ___waxy
cuticle_____________, that helps plants retain water. Pores called __stomata_________
are located in the epidermis of leaves. __Gas and water exchange
___________________ between the environment and the interior of the plant occurs
through stoma.
Vascular Tissue transports _water, mineral nutrients, and organic molecules_
______________________ between roots and shoots. It also contributes to the structural
support of the plant. Xylem transports _water_______ and __dissolved minerals
___________________ upward from __roots___ into ___shoots_____. Phloem
transports __food________ made in mature __leaves_____ to the _roots_____ and
parts of the __shoot system_________ that don’t carry out photosynthesis. Vascular
tissue is located in the ___centres_______ of roots, but in the stems it is arranged in
many separate _strands___ called ____vascular bundles__________.
A monocot stem has vascular bundles scattered throughout the tissue, where a dicot stem
have vascular bundles arranged in a ring.
Ground Tissue fills the space between the dermal and vascular tissue. It makes up most
of the young, non-woody plant and functions in _photosynthesis_________ in the shoot
and in ___storage_________ and ___support________ throughout the plant. The ground
tissue of the root consists of a mass of cells called the _cortex________.
TYPES OF PLANT CELLS
Define the following:
Parenchyma cell- thin-walled cells with large central vacuoles
Collenchyma cell- plant cells that have unevenly thickened cell walls
Sclerenchyma cell- plant cells specialized for support that grow and then die in
mature plant tissue
See Fig. 14.18, pg. 388
CELLULAR STRUCTURE OF A LEAF
Leaves are designed to capture sunlight and allow _gas exchange______ between the
surrounding air and the _cells__ inside the leaf that carry out _____photosynthesis.
See Figure 14.19, pg 389.
Describe the upper and lower surfaces of the leaf:
 Covered by tightly packed epidermal cells, covered by a waxy cuticle (reduces
water loss)
 Lower surface contains stomata (pores) surrounded by guard cells,
What do the guard cells do?
regulate the opening and closing of the stomata (letting in or out water vapour
or gases)
The ground tissue of the leaf is made of ___mesophyll________________, a type of
parenchyma cell that is specialized for __gas exchange_________. Under the upper
epidermis is a layer of elongated _palisade mesophyll_________________ cells that are
specialized for capturing __light energy______________ and carrying out
__photosynthesis__.
Next to the lower epidermis is a layer of loosely packed ___spongy mesophyll______
cells . ___Air spaces_____________ within these cells allow ___carbon dioxide
and ___oxygen___________ to circulate within the leaf.
Sunlight (Energy) + Water + Carbon Dioxide  Glucose + Oxygen (Photosynthesis)
Glucose + Oxygen  Water + Carbon Dioxide + Energy (Cellular Respiration)
COMPARING MONOCOTS AND DICOTS
Angiosperms make up __90%______ of known plant species. Copy down Table 14.1,
page 390.
Feature
Cotyledons
Roots
Leaf venation
Leaf mesophyll
Flower parts
Developing shoot
Vascular bundles in stem
Secondary growth
Monocots
One
Fibrous
Parallel
One type
Multiples of 3
Protected by sheath
Scattered
Absent
Dicots
Two
Tap
Netted
Palisade and spongy
Multiples of 4 or 5
hooked
Arranged in ring
Often present