Lab 4 ~ Green Algae, Mosses, Club Mosses and Ferns

What is oogamy?

• oogamous reproduction involves a large, non-motile egg fertilized by a smaller, often motile sperm

What are all members of the kingdom plantae united by? (3)

• alternation of generations

• gametangia and sporangia with multicellular walls

• Embryos nourished and protected by a gametophyte

What are bryophytes commonly referred to?

• mosses

• they grow on the backside of the tree because they have fewer structures to withstand drought, so they like it moist

What is the apex of the sporangium called and what does it do?

• operculum: protects the entrance to the spore-producing region until spores are mature

What are the 5 major obstacles overcome to transition to land?

• prevent desiccation (drying out)

• absorb water

• transport nutrients and water

• support themself against gravity

• disperse/reproduce on dry land

What helps plants prevent drying out?

• a thick, waxy cuticle

What are stomata?

• since the waxy coating prevents photosynthesis, this structure allows for gas exchange

What helps plants absorb water and inorganic nutrients?

• rhizomes, a smaller version of roots

What helps plants transport water and nutrients?

• xylem: transports water and dissolved minerals: one way, only from roots to leaves

• phloem: transports sugars and hormones: two way to roots and leaves

What helped support the plants?

• a thick, secondary wall in vascular plants (xylem) called lignin

What helped the plants disperse?

• decay-resistant polymer called sporopollenin

What are plants that produce one type of spore vs more than one called?

• homosporous

• heterosporous

What is accomplished by the rhizomes in lyco— and polypodium?

• asexual reproduction