Plants

What limits plants

availability of phosphorus, nitrogen, and nutrients from the soil

Plant evolution

ordorcian time period-475 million years ago

derived from green algae

resembled moss, liverwarts, hornwarts

Plants

Multicellular

eurkaryotic

photosynthetic

use cellulose for carbohydrates

use chlorophyll

Bryophytes/non vascular plants

No vasular tissue

no roots, flowers, seeds, or fruit

needs water for reproduction using spores

Pteridiophytes/seedless vascular plants

Have vascular tissue

no seeds, no flowers, no fruit

needs water for reproduction using spores

leaf like

Gymnosperms

Have pollen

Have seeds which are cones

no flowers

use the wind for pollenation

Angiosperms

First to have fruits and flowers

90% of plants today

have seeds and pollen

eudicots

2 seed leaves

4 or 5 flower parts

netlike leaf veins

vascular bundles arranged as a ring

monocots

1 seed leaf

3 flower parts

paralel leaf veins

vascular bundles distributed randomly in ground tissue

Dermal Tissue

Outside of plant body

consists of the epidermis, parenchyma cells, trichomes, periderm, cork and cork cambium, and lenticels

Ground Tissue

most of interior

Vascular Tissue

pipes for delivering water and other nutrients

xylem and phloem

Plant Morphology

roots

stems

leaves

flowers

Shoot system

organ system above ground

Root System

organ system below ground

Roots

Anchor plants to the ground

absorb water and nutrients

conduct water and nutrients to shoot system

storage of photosynthate as starch

Fibrous Roots

Monocots

no central root

Tap Roots

Eudicots

centralized

lateral roots branch off

Modified Roots

Storage roots and Adventitious roots

Storage Roots

underground plant organs that store nutrients like starch, water, vitamins, and minerals

Adventitious Roots

plant roots that form from any nonroot tissue

Shoots

Support

Photosynthesis

Transport

Storage

Reproduction

Terminal buds

top of main shoot or branch

axillary buds

base of leaves can become branches

vegetative shoots

photosynthesis

reproductive shoots

reproduction with flowers

Modified Stems

Stolons

Rhizomes

Tubers

Stolons

Above ground

asexual reproduction

Rhizomes

Horizontal

below ground

Asexual Reproduction

Tubers

Storage

Leaf Veins

have vascular tissue

xylem for water and nutrients

phloem for photosynthesis

Cuticle

Waxy hydrophobic lipid

protects leaf from drying out and acts as a protective barrier

Palisade Parenchyma

Photosynthesize

Stomata

Allows passive movement of water throughout the plant.

2 guard cells create pores that allow for gas exchange of CO₂ in and O₂ and H₂O out

Spongy Parenchyma

Allow air to circulate and do photosynthesis

Chollenchyma

supportive elastic cells

found in petioles and supporting central veins

Simple Leaves

1 blade

Compound Leaves

Leaflets

Double compound leaves

leaflets have leaflets

Modified leaves

tendrils

spines

succulent leaves

brightly colored

carnivory

Tendrils

help plants climb, grow, and compete for sunlight and space

Spines

protection

Succulent leaves

store water

brightly colored leaves

attract pollinators

carnivory

eat bugs to get nitrogen in nitrogen limited environments

Ground tissue

made of parenchyma

chollenchyma

and sclerenchyma

Parenchyma

All purpose

1 primary cell wall

divides and differentiates

Chollenchyma

thick wall

supports

flexible

1 primary cell wall

Sclerenchyma

Thick secondary walls

supports non growing sections

dead at maturity

Fiber cells

Sclereids

Tracheids

Long and Slender

water flows up and over

dead at maturity

vessel elements

barrel shaped

allow vertical flow

increased flow

dead at maturity

angiosperms only

Xylem fibers

non-living cells that support and strengthen xylem

Sieve tube members

Alive

has cytoplasm

no nuclei or organelles

companion cells

Alive

assist sieve tubes

has nucleus

only in angiosperms

Phloem Fibers

support for vascular tissue

made of sclerenchyma and dead at maturity

improves the strength of vascular tissue

what makes up wood

xylem

Parts of dermis tissue

Epidermis

Periderm

Epidermis

Primary dermal tissue, found in young parts of a plant

parenchyma cells

trichomes

guard cells

Trichomes

Hairlike extensions of epidermis, protects plants from predation, reduce evaporation

guard cells

form stomata and controls opening and closing them

Periderm

Secondary dermal tissue

cork and cork cambiam

Cork and Cork cambium

hardened protection in woody plants

Cork

Bark

Cork Cambium

Makes cork

lenticels

pores for gas exchange through outer cork and periderm, like stomata

Apical Meristems

create primary growth using cell division, the elongation of roots and shoots, plant embryoiotic cells that stay with them into maturity

located in axillary and terminal buds and root tips

Lateral Meristems

Create secondary growth by dividing cells in circular sheets throughout shoots and roots

in woody plants

increase circumferencf

allows plants to support themselves as they grow

Root apical meristem

makes root cap ahead of the meristem

makes primary vascular, grounds, and dermal cells behind meristem

cell division

replicate the meristem, make primary cells behind an root caps ahead

elongation

cell expansion creates force driving movement through soil

maturation

cells take on functional roles as vascular, ground or dermal tissue

stele

new primary vascular root cells

cortex

new primary ground root cells

protoderm

new primary dermal root cells epidermis

Root hair structure and function

extensions off root epidermal cells

increases root surface area

function to absorb water and nutrients from soil

shoot primary growth

at apical meristem, terminal or axillary bud

make 1st dermal, ground, and vascular shoot cells behind the meristem, build and adds length

perpetuate/replicates the meristem and leaves behind axillary bud meristem

lateral meristems

create cell division that increases girth/ circumference to support primary growth overtime

woody plants

make secondary tissue to make secondary growth

Vascular cambium

stem cells that form a cylinder in the shoot inbetween primary xylem and primary phloem in vascular bundles

makes secondary xylem to the inside and secondary phloem to the outside

cork cambium

makes secondary dermal tissue/ cork to outside

Vascular bundles

xylem and phloem in long tubes

indeterminate growth

roots and shoots

determinate growth

leaves

flowers

fruits

hypertonic

plasmolyed

isotonic

flaccid

hypotonic

turgid and preferred

water pressure

0 if the container is open

solute

0 if the water is pure

hydrogen bonds

make cohesions

water molecules

adhere to cellulose cell walls

casparian strip

made of wax/lipid

hydrophobic

forces water and nutrients to pass across at least 1 plasma membrane

permeable for ions

Apoplastic flow

through the cell wall cellulose

symplastic flow

through the cytoplasm and plasmodesmata

forced across membrane by casparian strip

what regulates the closing and opening of stomata

sunlight

adaptations in dry environments

stomata in protected pockets

trichomes decrease evaporation and create humid microenvirnments

Source

adds sugars to phloem and uses ATP

mature leaf, starchy storage root that releases sugars

Sink

Removes sugar from phloem, passive

anything that needs to grow

what makes soil acidic

roots

what has the greatest affect on plant growth

nitrogen

nitrogen fixing bacteria

only organisms that can break nitrogen’s triple bond

turns it into 2 ammonias

nitrifying bacteria

turns ammonium into nitrate which is preferred by plants