PLANTS
Characteristics
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•
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Eukaryotic, multicellular, nonmotile
Photosynthetic- autotroph
Have chloroplast:chlorophyll a and b
Cell wall made of cellulose- protects and
supports
• Cuticle- waxy covering that prevents
desiccation
Life Cycle
• 2 alternating cycles
• 2N- diploid sporophyte
• 1N Haploid gametophyte
Plant Needs
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Sunlight
Water and minerals
Gas Exchange
Movement of water and nutrients
Plant Adaptations
How did plants move from water to
land?
1. Vascular tissue: xylem carries water from
roots, phloem carries food made in leaves
2. Cuticle—prevents water loss
3. Roots- anchor the plant, absorbs water and
nutrients
4. Pollen- male sperm- doesn’t need water to
distribute
5. Seeds- provide protection and food supply to
embryo
4 MAIN TYPES OF PLANTS
Bryophyte
Pterophyte
Gymnosperm
Angiosperm
Common
Name
MOSSES
FERNS
PINES
FLOWERING
Vascular
tissue
No
Yes
Yes
Yes
Male
gamete
Flagellated
sperm
Flagellated
sperm
Pollen
Pollen
Dominant Gametophyte Sporophyte Sporophyte
Generation
Sporophyte
Mosses
• No vascular tissue and
produce flagellated
sperm- so need to be in
close contact with
water
• No roots- rhizoids
anchor to ground
• Peat moss- used for fuel
Ferns
• Flagellated sperm
• Has vascular tissue
Gymnosperm
• Vascular tissue
• Has male and female
cones
• Male cone produces
pollen
• Female cone produces
ovules
Angiosperm
• Produce flowers
• Produce seeds within a
“fruit”
• Vascular tissue
• Green(Herbaceous) or
woody stem
2 Types of Angiosperms
• Monocot- Grasses, lilies
• Dicot-Shrubs, trees,
flowers
• Annuals- live 1 year,
have herbaceous or
green stem(replant)
• Perennial- trees and
shrubs
• Biennial- takes 2 years
to grow-root storage
like carrots
Monocot vs. Dicot
Vascular Bundle Vascular Bundle Vascular Bundle
in Leaf
in Stem Cross
in Root Cross
section
Section
Flower groups
Monocot
Parallel
Scattered
Ring
3’s
Dicot
Web like
Ring
X
4’s and 5’s
3 Types of Plant Cells
• Parenchyma- storage and food production
• Collenchyma- found in areas of current growth
• Sclerenchyma- thick walled cells used for
support, also fiber, and grit in pears
3 Types of Plant Tissues
1. Dermal- makes up epidermis-protects- secretes
cuticle
2. Vascular- set of “pipes” that transport materials
far distances. Xylem carries water (tracheids and
vessel elements)
Phloem carries food(sugar)(sieve
tube elements and companion cells)
3. Ground – sites of photosynthesis(leaves),
storage(roots), and support(stems)
Plant growth
Meristematic tissue- site of actively dividing
cells(mitosis). Found at tip of shoot(called
apical- at the top) and the tip of the root.
Apical meristem found at the top of the shoot
and bottom of the root.
Plant organs
• Roots
• Stems
• Leaves
Roots
• help anchor plant, absorb nutrients, have root
hairs to increase surface area
• 2 types- fibrous
taproot
(food storage like carrot)
Monocot
(vascular
bundle
arrangement
)
Dicot
• Root cap at end of the
root- protects new
,growing cells. Also
produces lubricant so
root can move
through soil.
Stems
• Support the leaves
• 2 types- herbacous- green
•
woody
• Monocot (vascular bundle arrangement) Dicot
Leaf
• Site of photosynthesis
• Palisade mesophyll and spongy mesophyllphotosynthesis cells.
• Spongy mesophyll loosely packed – spaces where
the gases can be stored.
• Vascular bundle contains the xylem and phloem
• Stomata open during times when water loss is
low(early day or late afternoon)
• Loss of water through stomata called
TRANSPIRATION
Stomata- opening in the leaf that allows gas
exchange- O2 out and CO2 in for
photosynthesis.
Guard cells control the opening of the stomata.
When guard cells fill with water, stomata
open. When water leaves guard cellsstomata are closed.
Water transport
• What moves water up against gravity?
• Root pressure- movement of water coming up
from the roots
• Adhesion- water sticks to sides of xylem cells
• Capillary action- water attracted to itself and
the tube
• Transpiration- when stomata open- help pull
the water up- negative pressure
STOMATA
Flowers
• Reproductive organ of a plant- contains the
male and female parts
• Plants do not self fertilize- mechanisms in
place that doesn’t allow it.
• Male- stamen (anther and filament)
• Female –carpel (stigma, style and ovary)
• Petals- attract pollinator
• Sepal- green leaf surrounding flower
Plant Hormones
• Auxin- cell elongation
• Gibberellins- promote growth
• Cytokinin- stimulate cell division,growth of
lateral buds
• Ethylene gas- promotes fruit ripening
Tropism• plant response
to external stimulus
like light or gravity
• Thigmotropismresponse to touch-vines
Photoperiodism
Short Day Plants
• Short day, long night
• Can interrupt night to stop
flowering
• Poinsettia
Long Day Plants
• Long day, short night
• Increase night to stop
flowering
• Iris