What group of green algae is the closest relative to plants?
Charophytes.
What are the three traits shared by plants and charophytes?
Rings of cellulose-synthesizing proteins; structure of flagellated sperm; formation of a phragmoplast.
What is sporopollenin?
A polymer that prevents exposed zygotes/spores from drying out.
What is alternation of generations?
A life cycle including multicellular haploid and diploid stages.
What are embryophytes?
Plants with multicellular, dependent embryos protected by parental tissue.
What do sporangia produce?
Walled spores via meiosis of sporocytes.
What are archegonia and antheridia?
Female gametangia producing eggs; male gametangia producing sperm.
What is an apical meristem?
A region of cell division at roots/shoots enabling growth.
What is the function of cuticle and stomata?
Cuticle prevents water loss; stomata regulate gas exchange.
What distinguishes vascular plants?
Presence of xylem, phloem, roots, leaves, sporophylls.
What is the function of xylem?
Conducts water and minerals, includes lignin-strengthened tracheids.
What is the function of phloem?
Transports sugars, amino acids, and organic products.
What are microphylls vs megaphylls?
Microphylls: small leaves with one vascular strand; Megaphylls: large leaves with branching veins.
What are bryophytes?
Nonvascular plants: mosses, liverworts, hornworts.
What is a protonema?
Early moss gametophyte with large surface area for absorption.
What structures make up a bryophyte sporophyte?
Foot, seta, capsule.
What is peat?
Partially decayed organic material from wetland moss.
What benefits did ancient plant ancestors gain when moving onto land?
More sunlight, higher CO2, and nutrient-rich soils.
What challenges did early plants face when colonizing land?
Lack of structural support and risk of drying out.
Why are cuticles important for land plants?
They prevent desiccation and provide protection.
What is the function of stomata?
Gas exchange and regulation of water loss.
What role do mycorrhizal fungi play?
They transfer nutrients to plant roots and aid colonization.
What allowed vascular plants to grow taller than bryophytes?
Xylem and phloem transport tissues.
What is lignin?
A polymer that strengthens cell walls, enabling upright growth.
