Plant Diversity Flashcards
(36 cards)
What is the sporopollenin and where is it found?
A layer of durable polymer that prevents exposed plant zygotes from drying out. It is found in plant spore walls.
What four key traits do land plants share with only charophytes?
- Rings of cellulose-synthesizing complexes.
- Peroxisome enzymes
- Structure of flagellated sperm.
- Formation of a phragmoplast.
What are the four key traits that appear in nearly all land animals?
- Alternation of generations and multicellular, dependent embryos.
- Walled spores produced in sporangia.
- Multicellular gametangia.
- Apical meristems.
Why are land plants referred to as embrophytes?
The embryo is retained within maternal tissue.
What are sporangia? Gametangia?
Sporangia are organs which produce spores. Gametangia are organs which produce gametes.
What are female and male gametangia and what do they produce?
Archegonia are female gametangia that produce eggs and are the site of fertilization.
Antheridia are male gametangia that produce and release sperm.
What is the difference between vascular plants and nonvascular plants (bryophytes)?
Vascular plants contain conducting tissue (xylem and phloem) and can become taller and more wide spread.
Describe phylum hepatophyta.
Liverworts. Named for liver shaped gametophytes. Gametophytes may be flattened. Some have gametophytes with leaf like appendages.
Describe phylum anthocerphyta.
Hornworts. Sporophytes have long tapered shape. Lacks seta and consists only of sporangium. Gametophytes usually contain several sporophytes. Have symbiotic relationship with nitrogen fixing Cyanobacteria in soil.
Describe phylum Bryophyta.
Mosses. Commonly found as gametophytes. Green and photosynthetic when young but turn tan/brownish when ready to release spores.
What is the ecological importance of mosses?
Inhabit diverse and extreme environments. Some help retain nitrogen in the soil. Peat moss forms extensive deposits of partially decayed organic material. Can be used as a source of fuel.
What is the megaspore? The microspore?
The megasporangia produce megaspores that give rise to female gametophytes. The microsporangia produce microspores that give rise to male gametophytes.
Describe Lycophyta.
Club mosses, spike mosses, quillworts. Thrive in moist swamps. Surviving species are small herbaceous plants. Club/spike mosses are not true mosses(have vascular tissue).
Describe phylum Pterophyta.
Ferns, horsetails, whisk ferns, and relatives. Most diverse seedless vascular plants. Horse tails restricted to genus Equisetum. Whisk ferns resemble ancestral vascular plants but closely related to modern ferns.
What features are common to all seed plants?
- Reduced gametophytes
- Heterospory
- Ovules
- Pollen
What is an ovule? Pollen grain?
An ovule is a structure consisting of megasporangim, megaspore, and one or more productive integuments. Pollen grains are particles produced by microspores and contain the male gametophytes.
What is the evolutionary advantages of pollen over spores?
Pollen eliminates the need for a film of water; can be dispersed greater distances by air or animal.
What are gymnosperms?
A vascular plant that bears naked seeds- seeds not enclosed in protective chambers.
What is heterosporous? Homosporous?
Heterosporous is a plant species that has two kinds of spores: microspores and megaspores. Homosporous is a plant species that has a single kind of spore, which typically develops into a bisexual gametophyte.
Describe phylum Ginkgophyta.
Phylum consists of a single living species, ginkgo biloba. Has high tolerance to air pollution and is a popular ornamental tree.
Describe phylum Cyadophyta.
Individuals have large cones and Palm-like leaves. Thrived in Mesozoic but relatively few species exist today.
Describe phylum Gnetophyta.
Phylum comprised of three genera. Species vary in appearance and some tropical while others live in deserts.
Describe phylum coniferophyta.
Largest gymnosperm phyla. Most conifers are evergreens and can carry out photosynthesis year round.
What is a flower?
An angiosperm structure specialized for sexual reproduction.
