Download 22-4 Seed Plants

22-4 Seed Plants
Seed plants are the most dominant group of photosynthetic organisms on land.
Seed plants are divided into two groups:
1._______________________- bear seeds directly on the surface of __________.
2._______________________- flowering plants, bear seeds within a layer of
tissue that protects the seed.
Gymnosperms include _______________, cycads, ginkgoes, and gnetophytes.
Angiosperms include _______________, flowering trees and shrubs, and all
species of flowers.
Reproduction Free From Water
Seed plants have life cycles that alternate between a gametophyte stage and a
sporophyte stage.
They do not need water for fertilization of gametes.
Adaptations that allow seeds plants to reproduce without water include:
1.________________________________________________________________
2.________________________________________________________________
3.the protection of embryos in seeds____________________________________
Gametophytes grow within sporophytes called __________________ of the
gymnosperms and ________________ of the angiosperms.
Gametophyte generations live ________________ these structures.
The male gametophyte is contained in a tiny structure called a
_____________________.
Sperm does not need water to fertilize eggs; instead the pollen grain is carried to
the female reproductive structure by _______________, insects, or small animals.
The transfer of pollen is called _______________________.
A _______________ is an embryo of a plant that is encased in a protective
covering and surrounded by a food supply.
An _________________ is an organism in its early stage of development.
The _________________ surrounds and protects the embryo and keeps the
content of the seed from drying out.
Seeds may have specialized tissues or structures that aid in their dispersal.
 Some seed coats stick to the fur or feathers of animals.________________
 _____________________________________________________________
After fertilization, the zygote grow into a new plant---_______________________
The embryo can stop growing while in the seed, and can remain that way for a
long time.
When it grows, it uses the nutrients from the stored food.
The Four Main Groups of Gymnosperms are:
1.________________________________
2.________________________________
3.________________________________
4.________________________________
Gnetophytes:
 About 70 present-day species of the phylum gnetophyta are known, placed
in just three genera.
 Reproductive scales of these plants are clustered into cones.
Cycads:
 Cycads are palmlike plants that reproduce with ______________________.
 First appeared during the Triassic, 225 million years ago.
 Today only nine genera of cycads exist.
 They grow in __________________ and subtropical places.
Ginkgoes:
 Only one species exists—Ginkgo biloba.
 Planted in the US because of their resistance to ______________________
Conifers:
 Most common gymnosperms with more than ________ species
 Conifers include pines, _________________, firs cedars, sequoias,
redwoods. Junipers, and yews
Ecology of Conifers:
 Conifer leaves have specific adaptations to _________ conditions
 Most develop long, thin leaves, which reduce _____________________
 Their leaves have thick, waxy layers
 Most conifers are ______________________ and retain their leaves all
year.