Plants

Haplontic

A life cycle in which there is a dominant haploid stage

Diplontic

A life cycle in which diploid is a dominant stage

Gametophyte

• haploid

• dominant in lower plants

• gen became smaller through evolution

Sporophyte

• Diploid

• gen became more dominant through evolution

• dependent on the gametophyte in nonvascular plants

Apical Meristem

Addition of new cells in a root occurs

root cap

protects the fragile apical meristem as the root tip is pushed through the soil by cell elongation

Early Plants

nonvascular

Rigid molecule in stems

supports taller growth

Vascular tissue

developed for the transport of water and food derived from photosynthesis, allowing plants to grow taller away from water source

Xylem

conduct water and minerals from soil up to the shoot

Phloem

transport products of photosynthesis throughout the entire plant

Waxy cuticle

• protects leaves and stem from desiccation

• prevents intake of CO2

Non Vascular, seedless plants

Bryophytes

Vascular, seedless plants

Lycophytes and Pterophytes

Vascular, seed plants

Spermatophytes

Bryophytes

(Liverworts-Hepaticophyta, hornworts-Anthocerotophyta, mosses-Bryophyta)

• They generally lack lignin and do not have actual vascular tissue. Water and nutrients circulate inside specialized

conducting cells

• Gametophyte is dominant

• Archegonia produce haploid egg

• Antheridia produce haploid sperm

Lycophytes

Club mosses, quillworts, spike mosses

Pterophytes

whisk ferns, horsetails, fern

Spermatophytes

gymnosperms and angiosperms

Streptophytes

Land plants and closely related green algae

Bryophyta - mosses

• Haploid spore germinates to, first,

form protonema

• Gametophyte consists of

photosynthetic stem and foliage-

like structures, and rhizoids form at

the base of gametophores.

• Gametangia of both sex develop

on separate gametophores.

• The antheridium produces many

sperms, whereas the archegonium

produce a single egg.

• The zygote develops into

sporophyte after fertilization and

still attached by it foot to the

gametophyte.

microphyll

small and has a simple vascular system with a single unbranched vein run through the center of the leaf

Megaphylls

larger leaves with a pattern of branching veins

Sporophylls

leaves that were modified structurally to bear sporangia – mature fern fronds, flowers

Strobili

cone-like structures that contain sporangia – pine cones