Plant Diversity I: How Plants Colonized Land

A comprehensive set of vocabulary flashcards covering key terms and concepts regarding plant diversity and evolution.

Plant Species

There are 325,000 known plant species, most of which live on land.

Eukaryotic

Plants are multicellular, eukaryotic organisms that are photosynthetic autotrophs.

Charophytes

The closest algal relatives to land plants, freshwater algae that inhabit shallow waters.

Sporopollenin

A tough layer developed by charophytes around gametes that shares similarities with plant spores.

Alternation of Generations

A life cycle pattern in which plants alternate between two generations: sporophyte (2n) and gametophyte (n).

Sporangia

Multicellular organs where sporophyte generation produces spores, protected by sporopollenin.

Apical Meristems

Regions of cellular division and growth found in the roots, tips, and stems of plants.

Cuticle

A waxy polymer that coats the outer surface of leaves and stems, preventing desiccation.

Stomata

Specialized pores on the outer surface of leaves that allow gas exchange.

Bryophytes

Nonvascular plants, including liverworts, mosses, and hornworts, that are dominated by gametophyte generation.

Rhizoids

Structures anchoring gametophytes to the ground, similar to roots but not true roots.

Antheridiophore

A specialized structure that contains antheridia, which produce sperm in gametophytes.

Archegoniaphore

A specialized structure that contains archegonia, which produce eggs in gametophytes.

Flagellated Sperm

Sperm that requires water to aid in fertilization, common in bryophytes.

Sphagnum Moss

A type of moss known for its absorbent qualities, often used in peat.

Peatlands

Boggy regions with high amounts of peat, formed from Sphagnum moss.

Homosporous

A type of sporophyte produce one type of spore, leading to a bisexual gametophyte.

Heterosporous

Plants that produce two types of spores: megaspores and microspores.

Megaphylls

Large leaves with a branched vascular system, allowing for increased photosynthesis.

Microphylls

Small, spine-shaped leaves with a single strand of vascular tissue.

Sporophylls

Modified leaves that bear sporangia.

Peristome

Teeth-like structures that protect maturing spores and aid in spore release.