Overview of Plants:
All plants are multicellular & contain chlorophyll inside of chloroplasts
Plants (also called autotrophs or producers) trap energy from the sun by photosynthesis & store it in organic compounds
Heterotrophs or consumers get their energy directly or indirectly from plants
Plants also release oxygen needed by consumers
All plants are multicellular, eukaryotic organisms that reproduce sexually
Many medicines are produced by plants
Plants are very diverse & may be terrestrial or aquatic
Vary in size from 1 mm in width to more than 328 feet
May live a few weeks or some over 5000 years
Kingdom Plantae is divided into 12 phyla or Divisions
More than 270,000 plant species identified, but new species still unidentified in tropical rain forests
Terrestrial Adaptations:
· Plants probably evolved from green algae

· Both algae & plants have chlorophyll a & b, have cell walls made of cellulose, and store energy as starch

· First land plants had to develop adaptations to scarcity of water & climate changes (air temperature changes more rapidly than water temperature)

· Moving onto land allowed more sunlight, nutrients, & CO2 for photosynthesis

· A support adaptation included a compound called lignin (a hard substance that strengthens cell walls so they can support additional weight)

· The origin of vascular tissue (specialized tissue for carrying food , water, & minerals) was an evolutionary breakthrough in the colonization of land

· Plants with vascular tissue are known as Tracheophytes

· Two types of vascular tissue developed — xylem & phloem

· Xylem carries water & inorganic nutrients from the roots to the stem & leaves

· Phloem carries carbohydrates made by the plants to wherever they’re needed or stored in the plant

Copyright Holt, Rinehart, & Winston

Some plants formed woody tissue from xylem for extra support, while others kept a flexible, non-woody stem (herbaceous plants)
Greater amount of water lost by evaporation (transpiration) on land
A waxy covering or cuticle developed on all plant parts exposed to air which slowed transpiration (water loss)

Gases (carbon dioxide & oxygen) had to be able to move into & out of the plant
Openings in the cuticle called stomata allowed movement of gases
Two guard cells on each side of a stoma helped open & close the opening

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· When guard cells lose water & shrink, the stoma closes (prevents water loss in the hotter times of the day)

· When guard cells swell with water, the stoma opens for gas exchange

copyright McGraw-Hill

Other structural adaptations to land included roots for absorption of water and minerals leaves for gas exchange and photosynthesis
Reproductive Adaptations:
· To be successful on land, plants had to develop protective seeds for their embryos with stored food or endoderm

Copyright Holt, Rinehart, & Winston

Seeds are better at dispersal than spores
Classification of Plants:
They’re are 12 Divisions of plants divided into two main groups based on the presence of vascular tissue
Nonvascular plants lack vascular tissue and do not have true roots, stems, or leaves (mosses, liverworts, & hornworts)
Most plants have vascular tissue with true roots, stems, & leaves, but may or may not produce seeds

as said before: their wood is very resistant to disease and insects and water / rot.

also I would guess that their bark is extra thick/tough for fire resistance, and they have very high branches to avoid under story brush fires.