Tropisms
What are plant hormones?
 Chemical substances that control a plant’s patterns of
growth and development.
Kingdom Plantae
What is a target cell?
 Cell that has a receptor for a particular hormone.
Four Characteristics of Plants:
Cell Type: eukaryotic
Cell Structure: cell walls of cellulose
Cell Number: multicellular
Mode of Nutrition: autotrophic
What are trophisms?
 Response of a plant to an environmental stimulus.
What pigments do plants use to carry out photosynthesis?
 Green pigments chlorophyll a and b.
What are auxins?
 Substance produced in the tip of a seedling that stimulates
cell elongation.
Plant Life Cycle: Alternation of Generations
(Label the phases, diploid of haploid)
Trophism
Description
Gravitrophism
Response of a plant to the forces of gravity.
Phototrophism
Tendency of plant to grow toward a source of light.
MEIOSIS
Gametophyte Plant (N)
Thignotrophism Response of plants to touch.
What is photoperiodism in a plant responsible for?
 The response of plants to periods of light and darkness.
What are herbicides?
 A compound what is toxic to plants.
FERTILIZATION
Sporophyte Plant (2N)
Haploid (N)
Gametophyte plant (N);Produces either sperm or eggs.
(gametes = reproductive cells)
Diploid (2N)
The sperm and egg join to create the Sporophyte plant (2N),
which is diploid; Egg and sperm join to create spores by
meiosis.
Flowers (Reproduction)
Four Groups of Plants and Examples:
Bryophytes, mosses
Seedless Vascular, ferns
Gymnosperms, cone-bearing
Angiosperms, flowering
Three evolutionary developments among plants:
1. Vascular tissue
2. Seeds
3. Seeds enclosed in fruit
Four things plants need to survive:
1. SUNLIGHT– to carry out photosynthesis.
2. WATER & MINERALS
3. GAS EXCHANGE
4. Movement of WATER & MINTERALS.
Flower Functions
Petal
Anther
oval sac there meiosis takes place
Filament
long thin stalk that supports anther
Stigma
top of the style, sticky.
Style
stalk of the carpel
Ovary
broad base, contains 1 or more ovules
Ovule
egg
Stamen
Carpel/Pistil
Sepal
The majority of plant life is … FLOWERING PLANTS.
brightly colored, attract insects and other pollinators.
outer-most part, green, resembles leaves.
What is a fruit?
 Ovary walls are fruit which encloses the developing seeds.
List 3 ways seeds are dispersed?
 Animals, wind, water
What are ways flowers are pollinated?
 Wind
 Animals
Give 2 environmental factors that can cause a seed to germinate
 Temperature and moisture
Leaves (Cont.)
What is the function of the stomata?
 Outside layer of leaf opening in epidermis where gas and
water exchange (controlled by guard cells).
What is Turgor pressure?
 Water pressure
What happens to the stomata with high Turgor pressure?
 Stomata opens
What happens to the stomata with low Turgor pressure?
 Stomata closes
Bryophytes (Mosses)
Examples:
 Sphagnum moss
 Liverworts, hornworts
 What does the moss life cycle depend on for reproduction?
Life cycle/reproduction depends on water for reproduction
(no vascular tissue).
 What environment will you most likely find moss? Wet,
marshland
 Name two ways sphagnum moss is used? Sphagnum moss is
used in gardening to retain moisture in soil or as compacted
(peat) used as fuel.
Ferns: Seedless Vascular Plants
Examples:
 Club mosses
 Horse tail
Leaves
Photosynthesis: Process that plants use to produce their food
Transpiration: Loss of water and exchange of carbon dioxide
Evolutionary Development:
 Vascular tissue: specialized tissue to transport
water and nutrients throughout the plant.


“Leaves” on ferns are called fronds.
What is the “stem” of a fern called? rhizome
Vascular Tissue (Veins):
 Xylem moves water (H2O).
 Phloem moves nutrients and carbohydrates.

What are tracheids? Tracheids are specialized cells that can
move fluids.
Letter
Cuticle
Thick waxy layer, protects against water loss.
B
Epidermis
“Skin” of leaf - responsible for GAS EXCHANGE.
D

Ferns are members of the phylum Pterophyta.
In what kind of habitat are ferns most abundant? Moist,
shaded forest areas.
What are sori? Clusters of sporangia on underside of
fronds.
Function
A
C


Structure
Vein
(Xylem)
Vein
(Phloem)
E
Mesophyll
F
Stomata
G
Guard Cells
Pumps WATER up from soil through roots.
Moves NUTRIENTS and CARBOHYDRAYES throughout the plant.
Middle layers of leaf where PHOTOSYNTHESIS occurs.
Outside layer of leaf opening in epidermis where GAS and
WATER exchange.
Control stomata; trigger when water is LOW causing stomata
to become flaccid and pores CLOSE.
Stems (Transport in Plants)
Gymnosperms: Seed Plants
Types of stems:
Woody
Herbaceous
Means: “naked seed”
Examples: gnetophytes, cycads, ginkgoes, and conifers.
Second evolutionary development of plants: seeds; necessary for
plants to reproduce without water.
What is germination? Early growth stage of a plant embryo.
What is dormancy? Plant embryo is alive but not growing.
What is the function of sapwood?
 Area in plants that surrounds the heartwood and is active in
fluid transport.
What is the function of heartwood?
 Older xylem near the center of a woody stem that no longer
conducts water.
What does cork cambium produce?
 Bark
Function of stems:
1. Transports water & nutrients from roots to leaves.
2. Supports/produces leaves,
branches, fruits/flowers.
3. Stores food.
Explain capillary action:
 The tendency of water to rise up a
thin tube.
 Contributes to movement of water
up cells of xylem tissue.
Three features that allow seed plants to
reproduce without water:
1. Reproduction in cones .
2. Movement of gametes by pollination.
3. Protection of embryo in a seed.
Embryo: growing part of seed
Endosperm
Seed Coat: protection
What is pollination? Transfer of pollen from the male
reproductive structure to the female reproductive structure.
Adaptations: needles and winged seeds
Angiosperm: Flowering Plants


What is the reproductive organ of a plant?
o Flower
Two functions of flowers:
o Holds ovaries
o Attracts animals
Roots (Transport in Plants)
Types of Root Systems:
 Taproot: primary root grows down from the stem with
secondary roots forming.
– ex. carrot, potato, radish
 Fibrous: small lateral roots that spread out just below surface
of the soil.
– ex. weeds
Four Root Functions:
1. Absorbs water & nutrients from the soil.
2. Transports water & nutrients to stem.
3. Anchors plant to maintain stability.
4. Stores food and water.
Parts of a Root:
Outermost layer of root.
Stores starch.
Within cortex, contains
cells for transport of
water and nutrients.
Lifespan of Plants:



Annuals
– Complete life cycle in one year
Biennials
– Life cycle takes 2 years
 Year one: germinate and grow roots, maybe leaves
 Year two: grow new stems, leaves, and flowers
Perennials
– Live through many years
 May die back in winter, but re-grow in the spring (asparagus,
peonies, many grasses)
 Most have woody stems (palms, trees, honeysuckle)
Root Cap
Protection of root tip.