Chapter 16 Summary

March 12, 2012
Ch 16, plants, fungi, and the move onto land

Plants are extremely important to all living things on the Earth. It porvides numerous essential things needed for survival, like food for nearly all living things, it exchanges gasses for oxygen, which is needed for us to survive, paper, building materials, shelter clothes, things like rubber, and so on. unfortunately, plants are being wiped out more than ever before in their existence, all because of people. Plants are being killed faster than they can regrow, which could cause a mass extinction worse than any other.
the kingdom of plants are eukaryotic, multicelled, and use photosynthesis as a means of getting food/energy.

vocab
stomata: pores under leaf for gas exchange
cuticle: waxy layer on leaf that help the plant reduce water loss
Lignin: hardens cell wall
In vascular system
Xylem: transports water up stem/roots
Phloem: transports food
Yhe 4 major groups of plant evolution
Bryophytes: mosses
Ferns: vascular system
Gymnosperms (means "naked seed"): coniferous trees, first seed plants
angiosperms: flowering plants

Bryophytes have flagellated spores, and the only one whith gametophytes as the more primarily seen (over sporophytes)

Need damp places to fertilize because still dont have seeds and need to disperse

Moss doesn't have lignin

Ferns

12000 species, usually in tropics or temperate woodlands in the US.

first to have phloem and xylem

still no seed, sperm flagellated, so need damp environment

sporophytes dominant stage

Gymnosperms (naked seed)

have cone seeds, on dry land, can withstand harsh winters

thick cuticles and stomata, has lignin

sporophyte dominant, gametophytes are the cones

has pollen in male cones

wind carries pollen to female cones, not water

female cones contain eggs and ovaries

male cones are smaller, female cones higher on tree to help with the dispersion of seeds

Angiosperms

dominate almost any region on earth

250000 species

supply nearly all food and fibers

better vascular system, more efficient

has flower, caused to be one of the most sucessful types of organisms ever

flower have male (stemen: anther and filament) and female (pistol/carpel: stigma, style, ovary) parts on a flower

extremely diverse, doesn't have to rely on wind or water

has double fertilization: one sperm to egg, one to a polar body which then creates a endosperm that contains a large amount of nutrients used until the plant can photosynthesize

fruit are actually matured ovaries, they help protect and disperse the seeds

Next scribe: whoever kiran said