Evolutionary history of Biological diversity

2.7 billion yrs ago = oxygen 2.1 billion years ago = eukaryotes 1.7 billion years ago = multicellular euk. 500 million years ago = plants, fungi, animals

Gram staining

Nitrogen fixation

-Eukarytoic -Mostly unicellular -Aerobic

Endosymbiotic theory

Green algae  Land Plants Evidence: Similar chloroplasts Cellulose walls Peroxisomes sperm

Bryophytes Mosses/liverworts/ hornworts Reproduce using spores Avascular Gametophyte is dom. stage

Pteridophytes (ie ferns) Vascular No flowers or seeds Use spores Sporophyte dom. life cycle Kind of in between bryophytes and angiosperms/gymnosperms

Alternation of generations 2 multicellular stages -gametophyte (haploid) -gametes are produced -sporophyte (diploid) -fertilization of egg by sperm forms sporophyte

Gymnosperms conifer

Angiosperms (flowering) Monocots Parallel veins 1 cotyledon (seed leaf) Dicots/Eudicots Netlike veins 2 cotyledons

Double fertilization

mycelium

lichens

Sponges (parazoa) Filter feeders

Cnidarians Radial symmetry

Platyhelminthes (flatworms)

Nematoda (round worms)

Molusca

Annelida Segmented worms

Arthoropoda Segmented, exoskeleton bilateral

echinoderm