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BOTANY
The Study of the
plant kingdom
Examples
Characteristics of Plant
Kingdom
 Are multicellular eukaryotes that are
photosynthetic autotrophs
 Contain chloroplasts with chlorophyll a
 Cell walls made of cellulose
 Carbohydrates are stored as starch in plastids
 All undergo mitosis and nearly all have sexual
reproduction
Classification of Plants
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Kingdom - Plantae
Division (-phyta)
Class (-opsida)
Subclass (-idae)
Order (-ales)
Family (-aceae)
Genus
Species (Genus + specific epithet)
Magnolia grandiflora
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Plantae--includes all plants
Magnoliophyta--flowering plants
Magnoliopsida--dicots
Magnoliidae--subclass for Magnolia-like plants
Magnoliales--order for Magnolia-like plants
Magnoliaceae--family for Magnolia-like plants
Magnolia--genus that includes all Magnolias
grandiflora--specific epithet
Angiosperms
Flowering plants … are the most
widespread and diverse
 Classes include:
 Monocotyledons (Monocots)
 Dicotyledons (Dicots)
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Differences between
Monocots and Dicots
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Monocots:
flower parts in 3s
one cotyledon
scattered vascular
bundles
 parallel veins in leaves
 Fiberous root
 Examples: grass, lilies,
orchids
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Dicots:
flower parts: 4s & 5s
2 cotyledons
vascular bundles in rings
netlike veins in leaves
tap root
Examples: bean,
spinach, rose
Monocots vs Dicots
 Monocots:
 flower parts in 3s
 Dicots:
 flower parts: 4s & 5s
Monocots vs Dicots
 Monocots:
 one cotyledon
 Dicots:
 2 cotyledons
Monocots vs Dicots
 Monocots:
 scattered vascular
bundles
 Dicots:
 vascular bundles in
rings
Monocots vs Dicots
 Monocots:
 parallel veins in
leaves
 Dicots:
 netlike veins in
leaves
Monocots vs Dicots
 Monocots:
 fiberous roots
 Dicots:
 tap root
As Harriet turned the page, a scream
escaped her lips. There was Donald—his
strange disappearance no longer a
mystery.
Parts of flower
Structure of a Flower
1.Pistil:female reproductive structure
a.Stigma: sticky tip; traps
pollen
b.Style: slender tube;
transports pollen from
stigma to ovary
c.Ovary: contains ovules;
ovary develops into fruit
d.Ovule: contains egg
cell which develops into
a seed when fertilized
Stamen
Anther
Filament
Ovule
Stigma
Pistil
Style
Ovary
Petal
Sepal
Slide # 13
Structure of a Flower
Stamen: male reproductive structure
a.Filament: thin stalk;
supports anther
b.Anther: knob-like
structure; produces
pollen
c.Pollen: contains
microscopic cells that
become sperm cells
Stamen
Anther
Filament
Ovule
Stigma
Pistil
Style
Ovary
Petal
Sepal
Slide # 14
Structure of a Flower
Sepals: encloses & protects flower before it
blooms
Petals: usually colorful & scented; attracts
pollinators
Stamen
Anther
Filament
Ovule
Stigma
Pistil
Style
Ovary
Petal
Sepal
"And now we're going to play
she-loves-me, she-loves-menot!
 Occurs when a grain of pollen
lands on the stigma.
 If the pollen is from the right kind
of plant, and lands on the flower,
the pollen grain will break open
and its content produce a tube
that grows down through the style
into the ovule.
 When the tube has finished
growing , a sperm cell
emerges from the tube and
fertilizes the egg cell in the
ovule.
 If everything goes right,
pollination is followed by
fertilization
 During fertilization, the pollen
grain breaks out of the hard
cell wall.
 The fertilized egg and the
ovule that surround it become
( develops into ) the seed
Fruit
Ripened ovary that
protects dormant seeds
and aids in their dispersal
Fruit
 Fruit can be classified as being:
Fleshy: What we think of as fruit.
Dry Indehiscent: Do not open at
maturity
Dry Dehiscent: Open at maturity
Berry
 The endocarp is
liquid
 The exocarp is the
skin
 The mesocarp is the
meaty part you eat
Berry
Indian military has decided to use the
thumb-sized world's hottest chili to make
tear gas-like hand grenades to immobilize
suspects
It has more than 1,000,000 Scoville units, the scientific
measurement of a chili's spiciness. Classic Tabasco sauce
ranges from 2,500 to 5,000 Scoville units, while jalapeno
peppers measure anywhere from 2,500 to 8,000.
Hesperidium
 The endocarp is
liquid
 The exocarp is the
skin
 The mesocarp is the
white
Hesperidium
Drupe
 The endocarp
is stony
Drupe
Pome
Pepo
 The bumps on the
outside of the
cucumber are called
lenticel and function
in gas exchange
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Pepo
Aggregate
 The green is the
sepal
 The red is the
receptacle
 The seeds are called
achene
Multiple
 The Husk on the
outside are the
sepals
 Bob the Berry
 Larry the Pepo
Dry Indehiscent
(do not open at maturity)
 nut
 achene
Dry Indehiscent
(do not open at maturity)
 Samara: maple
 caryopsis
Dry Dehiscent
(open at maturity)
 Sililque: ex mustard
 Septacidal; ex yucca
Dry Dehiscent
 Follicle: Ex Milkweed
 Legume: ex Pea plant
Dry Dehiscent
 Locucidal: ex cotton
 Porocidal: ex poppy
Root System
 Functions:
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Anchorage
support
Absorption
translocation
 2 Broad
classifications:
1. Fiberous root
2. Tap roots:
Roots
 fiberous root:
 have numerous
roots of near equal
size growing in many
directions(Monocots)
Roots
 Tap roots:
 has one clearly
dominant root which
grows straight down
with smaller lateral
roots branching off (
dicots)
Monocot Root
Dicot Root
Dicot Root
ROOT GROWTH
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1.
2.
3.
Is concentrated near
root tip
Root tip contains 3
zones of cells:
Meristematic zone:
produces new cells
by mitosis
Zone of elongation:
cells elongate and
push meristematic
zone into soil…why
the roots grow in size
Zone of maturation:
No cell growth
ROOT GROWTH
Stems
Functions
food storage
support for leaves, flowers and fruit
Modified stems
 Corm ex gladiolus
 Bulb ex onion
Modified Stems
 Tuber ex irish potato
 Stolon ex grass
 Has horizontal stem
lays flat on surface of
ground
Modified Stems
 rhizome ex johnson
grass grows below
surface of soil
Modified Stems
 Tendril
 Cladodes
Modified Stems
 Thorns
 Rose thorns are not
thorns…they are just
epidermal outgrowths
Monocot Stem
Dicot Stem
Dicot Stem
2 ways Plants grow
1. increase in length=
Primary growth
2. Increase in width =
secondary growth
Leaves
 Photosynthetic part of plant
 Leaf venation can be: Parallel,
Netted (pinnately and
palmately)
 Simple compound
 1. Annuals: live for 1 growing
season and produce seeds
 2. Biennuals: produce only
vegetative growth 1st season and
viable sees before they die
 3. Perennials: live 3 or more years
and produce viable seeds each
year
Leaf types:
simple and compound ( palmately and
pinnately)
Leaf Structures
Leaf Cross-Section
Mesophyll
Cuticle
Veins
Stoma
(Opening)
2 Guard
Cells
Surround
each
Stoma
Stoma- singular
Stomata-plural
BOTANY
 Zea mays leaf, x.s.
 Leaf vein
Stomates and guard cells
Stoma is a small hole
Its size is controlled by 2 guard cells
closed
open
Stoma function is for gas
exchange in the leaf
Guard
cell
oxygen
Provided
plant is
photosynth
esising
Carbon
dioxide
Xerophytic Leaf:
 plant adapted to
extremely dry
environment
 has a thicker
cuticle,
 fewer to no
chloroplast
 reduced number
of air spaces
 crypts with sunken
stomata
Transverse Section Through Leaf of Xerophytic Plant
Mesophytic leaf:
live in moderant environment
Hydrophytic Plant:
* very little vascular tissue and
stomates
*Plants that have leaves
submerged in water
.
MONOCOT LEAF
MONOCOT LEAF
MONOCOT LEAF
DICOT LEAF
DICOT LEAF
 1. Parencheyma
cells:
 function in synthesizing and
storing organic products.
 2. Collenchyma cells: support
young plant parts without restricting
plant growth
 Schlerenchyma cells:
function in support
 2 types: 1. fibers 2. schlerids
 4. Water conducting cells:
 Xylem: dead cellls that carry
water and minerals ( 2 types:
tracheids and vessel
elements)
 4. Water conducting cells:
 Phloem: living cells that
function in transport of
organic material ( 2 types
sieve tube, companion
cells)
Flow of water in plant
 1. Water taken up by root hairs
 2. cortex
 3. endodermis
 4. pericycle
 5. root xylem
 6. stem xylem
Flow of water in plant
 7. leaf xylem
 8. leaf mesophyll
 9. substomatal cavity
 10. out through stomates