chapter 26

mitosis

single diploid cell to two identical diploid daughter cells

meiosis

diploid cell to four haploid cells

mitosis

single diploid cell to two identical diploid daughter cells

meiosis

diploid cell to four haploid cells

non seed plants

united by endosymbiosis of chloroplast (cyanobacteria) and photosynthesis

glaucophytes

ancient group, sister taxa to all plants, chloroplasts still contain peptidoglycan

red algae

can be unicellular or multicellular, red comes from phycoerythrin and choloorphyll a, color changes with depth in water (how does water interact with diff colors of light)

green plants

contain chlorophyll a & b and store energy as starch

chlorophytes

green plants; all green algae and all land plants, cells connected by plasmodesmata and grow apically (from top of plant)

land plants

had to overcome difficulties and leave water and colonize earth

cuticle

a waxy coating on the tops of leaves, prevents water loss due to heat from the sun

stomata

pores in green tissue that can open and close for water, gas and heat exchange

sexual reproduction is easier in water because…

gametes will naturally float away

gametangia

organs that enclose gametes until they’re prepared for dispersal

alternation of generations

divide between sporophyte and gametophyte promotes survivability and diversity

non-vascular plants

sporophyte small and dependent, gametophyte supports organism

liverworts

can reproduce sexually and asexually with cups called gemmae, body plan is leafy or thalloid

mosses

15,000 species, developed stomato for gas exchange, and becomes peat when compacted under moisture

hornworts

flat gametophytes and spike shaped sporophytes, nitrogen fixers, and can support indefinite cell division or flat gametophyte

vascular plants

the ability to conduct water throughout the plants allows them to spread across land, not just near water (still need water to reproduce)

xylem

vessel that conducts water and nutrients from the ground, up through roots, to the rest of the plant

phloem

conducts water and photosynthetic products from leaves to nourish the plant

tracheids

specialized cells in phloem and xylem that conduct water and provide support

lycophyte

vascular; have true roots, dichotomous branching, and simple spiral leaves called microphylls

horsetails

reduced leaves that grow in whirls, sporangia grow on stalks, silica in cell walls prevent them from being munched on comfortably

ferns

mostly terrestrial, have large branching leaves, sporangia grow on underside

euphyllophytes

finally have true vascular leaves (megaphylls) and overtopping growth

heterospory

division of gametophytes into male (pollen) and female (ovules)

rhizomes

horizontal stem

rhizoid

water absorbing filaments