This document provides information about plant structure and growth processes. It discusses the main plant parts including roots, stems, leaves, flowers, and fruits. It explains how plants transport water and nutrients as well as photosynthesis. The document also covers plant reproduction, classification, growth stages from germination to senescence, and how plant growth is regulated by hormones and environmental triggers.

2.  Learn the structures and characteristics of
plants.
 Understand how plants are named or
classified.
 Understand the growth processes of plants.
 Learn practical applications of botanical
knowledge.

3. Plant Cell

4.  Vegetative:
 Roots
 Stems
 Buds
 Leaves
 Reproductive:
 Flowers
 Fruit
 Seeds

5.  Anchor the plant
 Absorb water and
nutrients
 Store sugars from
photosynthesis
 Need oxygen to break
down sugars for growth

6. Sweet potatoes Beets

7.  Transport water and
nutrients
 Site of flower and leaf
attachment
 Support structure

8. BULBS – ONION,TULIP TUBERS - POTATO
Modified leavesModified stem
Many bulbs are modified stems

9.  Vegetative bud
 Flower bud
 Mixed bud

13. Catalpa Bedstraw (Galium)

14.  Attract pollinators
 Contain
reproductive
structures
 Fruits arise from the
mature ovaries
 Dioecious vs.
monoecious
Pistil
Perfect flower

15. MONOECIOUS DIOECIOUS
Alder
Persimmon

17.  Fruits are enlarged
ovaries left after other
flower parts drop
 Fleshy
 Drupe (peach)
 Pome (apple)
 Berry
 Achene (strawberry)
 Dry
 Nuts
 Pods – beans and peas

18.  Water uptake
(imbibition) causes
seed to swell
 Germination requires:
 Oxygen
 Proper temperature (70-
80°F)

20.  Plants within a family
have similar
characteristics
 Helps to narrow the
field when identifying
plants
Kingdom
Division
Class
Order
Family
Genus
Species

21. Genus – close genetically
Species – easily interbreed
Binomial
nomenclature

22.  Variety – naturally occurring
 Ex. Brassica oleraceae var. botrytis
(common name: broccoli)
 Cultivar – product of plant
breeding
 Ex. Acer platanoides ‘Crimson Sentry’
(common name: Crimson Sentry Norway maple)

23.  Universal
 Unambiguous
 Everybody knows
what you’re talking
about.
Chinese elm
(Ulmus parvifolia)

24.  Spore-bearing (ferns, mosses, hornworts)
 Seed-bearing
 Angiosperms
 Seed leaves called cotyledons
Gymnosperms (naked seeds – cone-bearing)
Angiosperms (enclosed seeds – flowering
plants)
Monocots (one seed leaf)
Dicots (two seed leaves)

25.  Most horticultural plants are vascular plants:
 Stems
 Leaves
 Roots
 Conducting tissues

26.  Bryophytes
 Liverworts
 Mosses
 Hornworts
Marchantia polymorpha
Common weed in nursery production

28. dicotmonocot

29.  Monocots =
grasslike plants
 Dicots = broadleaf
plants
 Selective herbicides

30.  Annuals – complete their lifecycle in one
growing season
 Biennials – require two growing seasons to
flower; often sold and cultivated as annuals
 Perennials – live for more than two growing
seasons
 Herbaceous perennials
 Woody perennials

31.  Annuals go through an entire lifecycle in one
season
 True annuals vs. frost-tender perennials
 True annuals live through only one lifecycle
regardless of climate
 Frost-tender perennials are native in climates with
warm winters – they are cultivated as annuals in
our cold-winter climate
 Winter annuals are grown in mild-winter climates
and are planted in fall for winter bloom

32.  Require two years to
complete their lifecycle
 First season growth
results in a small
rosette of leaves near
the soil surface
 Second season growth:
 Stem elongation
 Flowering
 Seed formation
Digitalis - Foxglove

33.  Plants that live and flower more than two
growing seasons
 Trees and shrubs are woody perennials - go through a
dormant phase each winter
 Bulbs (ex.Tulips) – leaves yellow and die back after
flowering – sugars are transported to and stored in
the bulb for flowering the next growing season
 Perennial garden flowers – plants die back to the
ground and enter a dormant phase over winter – grow
back from the root crown in spring
 Grasses – grow from the crown

36. GIRDLING DISRUPTS PHLOEM
TRANSPORT
SYSTEMIC HERBICIDES MOVE
THROUGHTHE PHLOEM

37.  Plants use light + CO2
and water to make
sugar.
 Sugars are used by the
plant for growth or
stored.

38.  Water and soil
nutrients are
transported up
through xylem.
 Sugars are
transported through
phloem.

39.  Occurs through the
phloem tissue
 Primary sink = Roots –
CHO storage
 2nd sink - Developing
flowers, fruits, and
seeds
 3rd sink are growing
points called
meristems
Electron micrograph of
a growing point

40.  Root hairs absorb
water and nutrients
 Cell elongation pushes
the root through the
soil
 Meristem produces
new root cells

41. or spike

44. Rooting
DepthRoot Hair
Stomate
2CO
Nutrients
Absorption

45.  Gas exchange occurs
through leaf pores
called stomata
 CO2 is taken up and O2
is released
 Water moving out
through stomata keeps
leaves cool
Stomate

46.  Intense sunlight
 Wind
 High temperature
 Low relative humidity

48.  Seed germination – Start of life for many
plants
 Juvenility – Stage of life cycle when plants put
on root and shoot growth
 Maturity – Flowering and sexual reproduction
occurs during this stage
 Dormancy - way for plants to survive
unfavorable conditions
 Senescence – Aging of the plant or its parts

49.  Auxins (IAA, IBA) – control growth of stems,
roots
 Cytokinins – work with auxins
 Abscisic Acid (ABA) – affects bud growth,
and seed, bud dormancy
 Gibberellins (GA) – important in seed
germination
 Ethylene – affects fruit ripening

50. MONOCOTYLEDON DICOTYLEDON

51. HEDERA HELIX (ENGLISH IVY)
STAYS IN JUVENILE STAGE FOR
10YEARS!
 Leaf form (Ivy)
 Growth form (suckers or
water sprouts)
 Thorns (Locust tree)
 Leaf retention (in young
trees, ex. oaks)
Juvenile Mature

52. Adventitious roots
Budding

53. HAMNER AND BONNER (1920’S)
PHOTOPERIOD RESPONSE
 Induction
 Cool temperature -
vernalization
 Night-length (long-day vs.
short-day plants)
 Initiation
 Vegetative meristems change
to flower meristems
 Development
 Pollination
 Fertilization

54.  Self-pollination vs.
cross-pollination
 Fertilization usually
required for fruit
development
 Exception:
Parthenocarpy
(produces seedless
fruit)
 Fertilized ovary
becomes the fruit

55.  Change in fruit color
 Softening of the
fruit
 Change in flavor
from sour to sweet
 Plant hormone
ethylene is involved
Ripening tomato fruit

56.  Senescence = aging
 Annual plants begin
senescence after
flowering
 Sometimes only
part of a plant will
senesce
 Mediated by
ethylene
Fall leaf color caused by
senescence of chlorophyll
(green) pigments allowing other
pigments to show

57.  Slowed or interrupted
plant growth
 Winter dormancy in
cold-winter areas
 Dry-season dormancy
in Southwest and on
coasts
 Seeds usually enter a
period of dormancy
after plant senescence.
 Breaking seed
dormancy:
 Cold-moist stratification
 Heat
 Scarification of seed coat
 Gibberellins
Nicking seed coat 24 hours later

59. Removing the apical bud release apical dormancy and results in growth
of axillary buds below the cut.

60. The effect of heading cuts differs, depending on bud arrangement.