Plants- Ch 30 Flashcards
What are the names of the four great episodes in the evolution of plants?
Bryophytes, pteridophytes, gymnosperms, angiosperms
What are the names of these four great episodes?
- ) the origin of bryophytes from algal ancestors
- ) the origin and diversification of vascular plants
- ) the origin of seeds
- ) the evolution of flowers
the evolutionary novelties if the first land plants opened an expanse of terrestrial habitat previously occupied by only films of__________
bacteria
What were some of the novelties?
spacious, bright unfiltered sunlight, abundance of carbon dioxide, soil was rich in mineral nutrients, relatively few herbivores or pathogens
what are the 3 phyla of bryophytes?
mosses, liverworts, and hornworts
what are the characteristics?
- usually no conductive tissue, sometimes poorly developed tissue
- gametophyte dominant
- sporophyte parasitic gametophyte
- need moist environment
- won’t live well in a desert
describe the structure: gametophyte
- gametophyte –> leady structure or thick conspicuous part
- produces archegonia and antheridia–> produce gametes
Are bryophytes a monophyletic group?
no
-diverged independently early in plant evolution, before the origin of vascular plants
__________ and __________ may be the most reasonable models of what early plants were like
Liverworts; Hornworts
True or False: Mosses are the bryophytes most closely related to vascular plants
true
What is the name of the oldest known vascular plant that evolved over 400 million years ago?
Cooksonia
What are Pteridophytes?
seedless vascular plants
What are the four phyla of seedless vascular plant?
- ) whisk ferns
- ) club mosses and quillworts
- ) horsetails and scouring rushes
- ) ferns
Whisk Ferns
also called Psilotophyta
- simplest of all living vascular plants
- enations
Club Mosses and Quillworts
also called Lycophyta
- sporangia clustered together in cones or strobili which protect them
- some heterosporous–microspores and megaspores
- necessary for evolution of seeds
Horsetails and Scouring Rushes
also called Equisetophyta
- single remaining genus-Equisetum
- flourished in the Carboniferous
- treelike, over 50,000 feet tall
There are three analogous structures called leaves. What are they?
- ) Leaves on gametophytes of nonvascular plants
- ) enations-microphylls
- ) megaphylls
True leaves/megaphylls are present in what groups?
all seed plants, ferns, some equisetophytes
Ferns and fernallies
also known as polypodiophyta
- 11,000 species
- all have megaphyll - fronds
- produce spores (megaspores and microspores)
- wind dispersed
- flagellated spore (water dispersed)
Seed plants evolved from what?
spore-bearing fern-like plants
What is a benefit of having seeds?
- ) protection for the embryo
- ) nourishment for the embryo
- ) easily dispersed
- ) introduce a dormant phase in the life cycle
Do seeds have a whole genome duplication?
yes
Seed -plants produce 2 kinds of gametophytes. What are they? Describe them
Male Gametophytes:
- pollen grains
- dispersed by wind or a pollinator
Female Gametophytes:
- egg develops within archegonia
- enclosed within diploid
Gymnosperms
- naked seed (on scale of female cone)
- no flowers or fruit
- most are trees and shrubs which means they are sporophytes and diploid
- more advances than seedless vascular
