23,24- Gymnosperms & Angiosperms

Alternation of independent heteromorphic generation

The process in which the new sporophyte, while developing from the zygote, is temperature dependent on a tiny gametophyte.

Evolution of seeds

The development of seeds in plants, which allowed the embryo to use the photosynthetic capacity of the leaves and roots of the previous sporophyte.

Gymnosperms

A division of seed plants that have "naked ovules," with ovules located on flat sporophylls.

Division Cycadophyta

A division of gymnosperms that includes cycads, which produce seed cones and pollen cones on separate plants.

Division Coniferophyta

A division of gymnosperms that includes conifers, which are the most diverse group of gymnosperms and are trees of moderate to gigantic size.

Division Ginkgophyta

A division of gymnosperms that includes the maidenhair tree, which contains a single living species and reproduces through seeds.

Division Gnetophyta

A division of gymnosperms that includes gnetophytes, which have vegetative features similar to cycads and produce cones containing both microsporophylls and megasporophylls.

Progymnosperms

An extinct group of plants that evolved 390 million years ago and had a vascular cambium that could produce large amounts of secondary xylem and phloem, but did not have seeds.

Seed Ferns

Woody plants with fernlike foliage that bore seeds instead of sori, and had leaves similar to true ferns in overall organization.

Angiosperms

A division of plants known as flowering plants, which have evolved from gymnosperms and have features such as double fertilization, bisexual flowers, vessel elements, and sieve tubes.

moss

tortula muralis

cinnamon fern

Osmundastrum cinnamomeum

Ginko tree

Ginkgo biloba

dogwood tree

Cornus florida

liverworts

Hepatophyta

mosses

Bryophyta

hornworts

Anthocerotophyta

club mosses

Lycophyta

whisk ferns

Euphyllophyta

horsetail

Equisetophyta

ferns

Polypodiophyta

seed ferns

Pteridospermophyta

conifers

Coniferophyta

cycads

Cycadophyta

cycadeoids

Cycadeoidophyta

maidenhair tree

Ginkgophyta

flowering plant

Magnoliophyta