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Two clades of seed plants

Gymnosperms and angiosperms

What is a seed?

plant embryo packaged with a food supply and protective coating

pines and conifers


flowering plants



reproductive structure that bears seeds within ovaries

gametophytes in seed plants

highly reduced, microscopic

sporangia of seed plants

heterosporous; megasporangia and microsporangia


tissues protecting megasporangium

fertilized egg develops into...

diploid sporophyte embryo, which then develops into a seed

pollen grains

microspores released from microsporangium


tough coat covering pollen grains


pollen grains carried by wind or animals until they land near ovule

fertilization tube

what pollen grain elongates into ovule to deliver sperm


reproductive structure consisting of a cluster of specialized leaves called sporophylls

seeds of gymnosperms

"naked;" develop on surfaces of sporophylls

two types of conifers

evergreen, deciduous

gametophytes of conifers

heterosporous; small pollen cones and larger ovulate cones

sperm of gymnosperms

do not have flagella

pine seed

embryo (new sporophyte) and food supply derived from gametophyte tissue

flowers and fruits


phylum of angiosperms; two classes

Anthophyta, monocots and dicots


pore in the ovule where pollen tube releases sperm cells

double fertilization

two sperm cells: one fertilizes egg and other fuses with two haploid to form triploid cell that will produce endosperm


rudimentary root and one or two seed leaves of angiosperm embryo


where food is stored for developing endosperm

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