Chapter 25: Seedless Plants

Plants share a common ancestor with _____ (green algae) in the archaeplastida supergroup of eukaryotes

Charophytes

Which groups of plants have algal ancestry

red algae

green algae (charophytes)

chlorophytes

embryophytes

What 3 groups share these characteristics?

multicellularity

cell walls with cellulose

chloroplasts with same pigments

storage molecule is starch

chlorophyte

charophytes

and plants

About 470 mya in the Paleozoic Era, multicellular ____ ____ expanded from shallow seas into rivers and lakes

green algae

Populations with land adaptations

thrive

What is one downside of land?

periodic dehydration

Advantages of being on land in early evolution

higher CO2

more light intensity

more minerals

no herbivores

no competition

also called drying out, is a constant danger for an organism exposed to the air

dessication

Plant ______ and ____ must be protected from desication

gametes, zygotes

Plants had to develop a _______ support mechanism in a medium that does not give the same lift as water

strucutural

How did plant gametes reach each other prior to land?

swimming

What are 2 main disadvantages of being on land

risk of desiccation

no support in the air

Lifecycle in all land plants exhibits the

alternation of generations

All plants have _____ haploid spores

walled

All plants have ________ gametangia

multicellular

Sporophyte embryos are protected within the female __________

gametophyte

Plants have an apical _______ in the tissue and the roots

meristem

a region of undifferentiated, actively dividing cells found at the tips of plant roots and shoots.

apical meristem

Plants have also evolved a ____ ____ that helps them resist desiccation

waxy cuticle

Plants have also evolved secondary compounds and ________, beneficial, symbiotic fungi that connect with plant roots to expand the root system's reach, dramatically improving water and nutrient uptake—particularly phosphorus—while increasing plant resistance to disease, drought, and transplant shock.

mycorrhizae

refers to life cycle in which there is a dominant haploid stage

haplontic

refers to a life cycle in which diploid is a dominant stage

diplontic

Most plants exhibit alteration of generations, where the gametophyte is ______ and the sporophyte is _______

haploid, diploid

which generation is dominant in lower plants?

gametophyte

As plants evolved, the_____- got smaller, whereas the _______ became more dominant

gametophyte, sporophyte

Compared to alternation of generations, the charophyte life cycle has only _______ as haploid and the zygote does meoisis to produce only ____ diverse offspring

multicelluar, 4

Plants have walled haploid spores, which are dispersed through air. THe _______ protects them

sporopollenin

Where are spores made?

in the multicellular sporangium

male reproductive organ or gametangium found in the gametophyte phase of mosses, ferns, fungi, algae, and other non-flowering plants.

antheridium

Multicellular ______protect the sperm within the antheridium

gametangia

a multicellular, flask-shaped female reproductive organ found in bryophytes, ferns, and some gymnosperms that produces and houses a single egg

archegonium

Eggs are protected within the archegonium, which is where _____ occurs, forming the zygote

fertilization

Each archegonia has a single

egg

continuously dividing cells

roots and shoots grow towards resources

apical meristems

waxy coat stops desiccation

pores needed to allow CO2/O2 exchange

controllable stomata in most plants

waxy cuticle

microscopic, mouth-shaped pores found primarily on leaf epidermises, surrounded by guard cells that regulate gas exchange and closing under stress or drought to prevent dehydration.

stomata

chemicals that deter, repel, or poison competitors, herbivores, and parasites

life caffiene or latex rubber

secondary metabolites

mutualism with fungi; helps water and mineral absorption

dates back to first land plants (before true roots)

mycorrhizae

Seedless nonvascular plants are called______

bryophytes

What were the first plants to exist outside of water?

bryophytes

What 3 types of plants are bryophytes?

liverworts, hornworts, mosses

nonwoody, small, ground-covering plants that require water for reproduction

have rhizoids for attachment (no true roots)

made of 3 phyla

Bryophytes

Marchantiophyta common name

liverworts

Antherocerotophyta common name

Hornworts

Bryophyta common name

mosses

Bryophytes have a haploid ________ as the dominant form that makes either eggs or flagellated sperm

gametophyte

Where would you typically find a bryophyte

small, low growing, moist areas

The diploid ________ depends on gametophyte for food and water

sporophyte

The sporophyte grows within the _________ of the gametophyte

archegonium

__________- makes many haploid spores

sporgangium

Liverworts (Marchantiophyta) most have elevated ______ that resemble miniature elevated trees, have reduced or very small sporophytes

gametophytes

The common name ___________ refers to horn-like long tapered shape of the sporophyte

hornworts

Which bryophytes are good colonizers of moist soils

hornworts

Which bryophytes have a symbiotic relationship with nitrogen fixing cyanobacteria

hornworts

Which are the most numerous of the non-vascular plants?

mosses (bryophyta)

Where can mosses live?

extreme environments, moutain tops, tundras, deserts

In mosses the ______ grows from the female gametophyte to gain elevation for spore dispersal

sporophyte

Which class of bryophytes is a “pioneer” species in nutrient-poor soils

mosses

Which species can be a major primary producers in cold or high altitude regions

mosses

Some _______ have preserved corpses for thousands of years

peatlands

Until ____ ____ evolved, all land plants were short, ground cover plants

vascular tissue

What are the 2 major divisions of vascular seedless plants

lycophytes, monilophytes

The oldest seedless vascular plants are ______ mya

about 425 mya

What are the 3 groups of lycophytes

club mosses

quillworts

spike mosses

What are the 3 groups of monilophytes

whisk ferns

horsetails

ferns

SVPs are branched ______ that are independent of gametophyte for nutrition

sporophytes

For SVP, the diploid ________ dominates the life cycle

sporophyte

SVP transport resources through what type of vascular system

xylem and phloem

cells specialized to move water and minerals

xylem

cells specialized to move sugars, amino acids, other organic products

phloem

SVP also marks the evolution of true _______ and _____

roots and leaves

Only lycophytes have ______ : small, spine-shaped leaves supported by a single strand of vascular tissue

microphyll

Almost all other vascular plants have _______: leaves with a highly branched vascular system with greater photosynthetic productivity

megaphylls

leaves modified to bear sporangia

sporophylls

Fern sporophylls look like normal leaves but have ____- that generate spores on the underside

sori

Lycophyte sporophylls are modified into a cone-like structure called a

strobilus

Lycophytes are

club mosses and relatives, spike mosses and quillworts

Monilophytes are

ferns and relatives

dichotomous branching

no true leaves or roots

homosporous

photosynthesis occurs in stem

whisk ferns

jointed stems with tiny leaves

strobili

homosporous

photosynthesis occurs in stems

horsetails

most widespread and diverse monilophytes

homosporous

large megaphylls

sori on underside of sporophylls

mostly in understory or as epiphytes

ferns

grows on the surface of a plant

epiphyte

Most seedless vascular plants have _______ spore production

homosporous

All seed plants and a few seedless vascular plants have ____________ spore production

Heterosporous

Homosporous spore production leads to a singular type of spore, which results in a _______gametophyte that produces both a sperm and egg

bisexual

The megasporangium (megasporophyll) and the microsporangium (microsporophyll) produce the mega and micro spore respectively, which produce the male and female gametophytes, then they make the eggs and sperm

heterosporous spore production

Spike mosses and quillworts are _________

heterosporous

Club mosses are _________

homosporous

Club mosses have ______ which are clusters of sporophylls

strobili

Monilophytes contain

whisk ferns, horsetails, and ferns

dichotomous branching

no true leaves or roots

homosporous

photosynthesis occurs in stem

whisk ferns

jointed stems

strobili

homosporous

photosynthesis occurs in stem

horsetails