Bio 1B 3.1 Seedless Plants

Describe the challenges to plant life on land

unfiltered UV harmed plants, desiccation, lack of structural support, couldn't easily disperse reproductive cells, lacked soil

What are the four adaptations that early plants evolved to live on land?

alteration of generations, apical meristem tissue in roots and shoots, waxy cuticle, and lignin

Plants are _________

haplodiplontic

what does it mean to be haplodiplontic?

Half of the organism's life is spent as a haploid and the other half as diplod

Describe the traits shared by green algae and land plants

chloroplasts contain same carotenoids and chlorophyll a and b, store carbohydrates as starch, and cell walls contain cellulose

Explain why charophytes are considered the closest algal relative to land plants

They lack supportive tissue like xylem and phloem that lands plants have, are haplontic, and have flagellated sperm

Identify the main characteristics of byrophytes

nonvascular, seedless, homosporous, they lack lignin, don't have true leaves or roots, and the gametophyte is dominant

what are the distinguishing traits of liverworts?

have air pores but not stomata, has rhizoids not roots, grows across the plant body not at the buds

what are the distinguishing traits of hornworts?

has pipe-like sporophyte, air pores are on the gametophyte but stomata are on the sporophyte

what are the distinguishing traits of mosses?

has a stalk with primitive conductive system, has leaflike blades with air pores, rhizoids act as its roots, sporophyte has stomata

Describe the events in the bryophyte life cycle

haploid spores germinate in the gametophyte to make gametospores, the sperm swim to and fertilize the egg in archegonium where a diploid embryo develops and turns into a sporophyte which produces haploid spores through meiosis

Identify the new traits that first appear in seedless vascular plants

large heights, has true roots stems and leaves, can be homosporous or heterosporous, posseses lignin cuticle and apical growth, diploid sporophyte dominant

Which plants are considered non-vascular?

Liverworts, hornworts, mosses

Which plants are vascular?

Club mosses, quillworts, spike mosses, whisk ferns, horsetails, and ferns

Which classes of plants are both seedless and vascular?

club mosses, quillworts, spike mosses, whisk ferns, horsetails, and ferns

What are the distinguishing traits of club mosses, quill worts, and spike mosses?

the sporophyte is dominant, consists of a small stem and microphylls, has strobili with sporangia

what are the distinguishing traits of whisk ferns?

photosynthetic stems with knob shaped sporangia, lacks roots and leaves

what are the distinguishing traits of horsetails?

thin leaves, toxic to livestock, contains silica in epidermic cells

what are the distinguishing traits of ferns?

dominant sporophyte, has true roots, stems, and leaves, has flagellated sperm

Describe the life cycle of a fern

spores from the sporangium release and fertilize the eggs in the archegonium, then it develops into a sporophyte which grows roots from the gametophyte that then touches the ground and is able to support itself

Explain the role of seedless plants in the ecosystem

seedless plants make the earth easier for other plants to grow on and provide resources to the environment

Liverworts, hornworts, and mosses are all ______phytes

byrophytes

club mosses, quillworts, and spike mosses are _____phytes

lycophytes

whisk ferns, horse tails, and ferns are ________phytes

Pterophytes

Define gametophyte

haploid form that produces haploid gametes by mitosis

define sporophyte

diploid form that produced haploid spores by meiosis

define sporangia

reproductive sac for spore production

define gametangia

structure that gives rise to gametes by mitosis

what is an antheridium?

male reproductive structure of a plant, produces flagellated sperm

what is an archegonium?

female reproductive structure of a plant, produced eggs and protects developing embryo

what does lignin do?

reinforces cell walls to prevent water loss and provide strength

what are megaphylls?

large leaves with a branching vein pattern

What are sporophylls?

leaves modified to bear sporangia

what are microphyll?

small leaf like stricture with a single unbranched vein through the center