General Biology II: Chapter 29

Land Plants

Closest living relative of land plants?

charophytes

Which group is considered the first land plant?

bryophytes (mosses, liverworts, hornworts)

Vascular System

tracheophytes, have tissue for conducting water and minerals throughout a plant

Examples of vascular plant groups

clubmosses, horsetails, ferns, gymnosperms (conifers), angiosperms (flowering plants)

What did the new adaptation of the vascular system allow?

they allowed plants to grow taller, become independent of water, and efficiently transport water, nutrients and sugar throughout the plant

Seedless Vascular Plants

no seeds, but have xylem and pholeum that help transport water and food

Seed Plants

reproduce using seeds

Nonvascular Plants

no vascular system xylem and pholeum, grow in moist environments

How did seedless plants affect earth and life?

they drove global cooling and creating coal deposits via CO₂ removal

What kind of adaptations did plants need to get to survive out of water?

waxy cuticle, stomata, development of vascular tissue, embryos, spores/seeds

How did adaptations of land plants benefit animals and other life?

plants supply oxygen & are the ultimate source of most food eaten by animals, allowed animals to diversify, and create new niches

Difference between spores and seeds

spores are not seeds, all plants have spores, but seed plants make them

Advantages of spores

dispersal, survival, reproduction, allow wide distribution by wind, water or animals

Advantages of seeds

protection, nourishment for embryo, enhanced dispersal capabilities, and ability to remain dormant to survive harsh conditions

Alternation of Generations

life cycle is characterized by this, plants alternate between 2 multicellular adult body forms

Alternation of generations in mosses

gametophyte n vs sporophyte 2n: gametophyte produces gametes that fuse to form a zygote, develops into sporophyte

Alternation of generations in ferns

diploid sporophyte vs haploid gametophyte: sporophytes produce haploid spores through meiosis

Alternation of generations in vascular plants

dominant, diploid sporophyte, smaller haploid gametophyte

sporophyte from a gametophyte stage

Photosynthesis

plants, algae and some bacteria convert light energy into chemical energy, making their own food from CO₂ and H₂O

Stomata

pores that facilitate gas exchange between the outside air and internal plant tissue

What is the risk stomata take by opening up for gas exchange?

excessive water loss