Plants Bio 130

plants are…

• alive, they feel and respond to their enviroment

• photosythetic(autotrophs), link beteween the sun energy and chemical energy

• sessile, don’t move

• have cell walls

autotrophs

make food out of sun energy and other nutrients, beling to kingdom plantae (eukaryotes)

intermediate growth

continue to grow throughout their lives

• phenotypic plasticity allows for stalling growth

4 main groups/phylla

• bryophytes (nonvascular, moss, etc.)

• seedless vasculars (ferns)

• gymnosperms (conifers)

• angiosperms (flowering/fruit-bearing)

big evolutionary steps

• multicelluarity

• vascular system

• seeds and pollen

• flowers and fruits

4 main resources needed for growth

• light

• water

• nutrients

• space

what are the shoots and their functions

• Usually aboveground.

• Includes stems, leaves, flowers, and fruits.

• Supports the plant.

• Performs photosynthesis and reproduction

what are roots and their functions

• Usually underground.

• Absorbs water and minerals.

• Anchors the plant.

• Stores nutrients

surface area to volume ratio

• high surface area is good for light exposure, absorbtion

• - bad for water loss and storage

• high volume is good for storage and less dehydration

surface area on shoots

• increased sun exposure (big fat leaves)

• increased water loss (more stomata to lose water)

• more danger from freezing, think of tree types in autumn

surface area on roots

• increase absorbtion

• decreased strength (pulling up grass v. pulling up a shrub)

• decreased storage

key functions of root system

• anchors the plants

• abrobs ions and water

• conducter water and ions

• stores molecules

tap roots

• more volume than surface area

• strength and storage

• vertical

lateral roots

• more surface areathan volume

• for absorbtion

• not very strong

what is root style determined by

natural selection- minimize competition for resources

modified roots

• anchor roots- anchor stems to walls

• prop roots- stabilize stems

• pneumatophores- allows for gas exchange

• storage- store sugars for later

shoot system

• stems

• leaves

• buds

stem structure

contains main part of vascular system

• nodes- where leaf is attached

• internodes- between nodes

what are leaves

the photosynthetic areas hat contain part of the vascular system

what are buds

they show future growth

• lateral buds- leaf attachment

• terminal bud- tip of the branch

modified stems

• water storage - cactus

• stolons- produce new indivisuals above ground

• rhizomes - storage

• tubers- carbohydrates storage

• throns - defense

leaf modification

• bulbs- food storage

• succulent leaves- water storage

• tendrils- aid climbing

• floral mimics- not real flowers (colorful leaves)

• traps- pitcher plants

plant tissue

• merismatic tissue - growth

• dermal tissue- outside surface

• vascular tissue- transport

• ground tissue- the rest

primary growth

inreases length

• extends roots and shoots

secondary growth

increases thickness

• adds layers (like trees)

• makes wood and bark related tissues

meristimatic tissue

growth tissue

• grow from the tip (primary) and/or add layers (secondary/lateral)

• at the tips of stems under the surface of the plants

• layers laid down immedietly under ht esurface of the plant

angiosperms

can be classified based on secondary v. primary growth - determines the arrangement of vascular bundles

• includes monocots and eudicots

monocot

scattered vascular bundles

• not lateral growth, only herbacous

eudicot

vascular bundles are in a ring

• lateral growth and woody vegetation