Chapter 17 Evolution of Plant and Fungi Diversity

What group of green algae did plants evolve from?

Charophytes

What are three key adaptations that allowed plants to live on land?

Waxy cuticle, stomata, vascular tissue (plus lignin for support)

What is the term for the plant life cycle alternating between haploid and diploid generations?

Alternation of generations

In mosses, which generation is dominant?

Gametophyte

In ferns, gymnosperms, and angiosperms, which generation is dominant?

Sporophyte

What are bryophytes?

Nonvascular plants (e.g., mosses) with dominant gametophyte generation

What distinguishes seedless vascular plants from bryophytes?

They have vascular tissue and a dominant sporophyte stage but still use spores (e.g., ferns)

What makes gymnosperms different from angiosperms?

Gymnosperms have seeds but no flowers or fruit (e.g., pine trees)

What makes angiosperms unique?

They have seeds enclosed in fruits and produce flowers (most diverse plant group)

Which angiosperm group includes grasses and lilies?

Monocots

Monocot vs Eudicots

Trait	Monocots	Eudicots

Cotyledons

1

2

Leaf veins

Parallel

Branched

Flower parts

Multiples of 3

Multiples of 4 or 5

Vascular bundles

Scattered

Ringed

How do fungi get nutrients?

Absorption (they are heterotrophic)

What are fungal cell walls made of?

Chitin

What are hyphae and what do they form?

Thread-like structures that form a mycelium (feeding body)

What do fungi reproduce with?

Spores

What fungi group includes bread mold and forms zygospores?

Zygomycetes

What fungi group includes yeast and morels?

Ascomycetes (sac fungi)

What fungi group includes mushrooms?

Basidiomycetes (club fungi)

Which fungi have flagellated spores and live in water?

Chytrids

What is mycorrhizae?

A mutualistic relationship between fungi and plant roots

What is lichen?

A mutualistic relationship between fungi and algae or cyanobacteria

Why are lichens important ecologically?

They are pioneer species in primary succession and help form soil

What were the main challenges for early plants colonizing land?

Drying out, reproduction without water, support against gravity, and nutrient/water absorption

What key adaptations helped plants overcome land challenges?

Cuticle, stomata, vascular tissue, lignin, embryo protection

Do bryophytes have vascular tissue?

No

Which generation is dominant in bryophytes?

Gametophyte

How do bryophytes reproduce?

With spores, and they require water for fertilization

Give examples of bryophytes.

Mosses, liverworts, hornworts

What feature defines vascular plants?

Presence of xylem and phloem (vascular tissue for transport)

What advantages do vascular tissues provide?

Support and transport of water/nutrients over longer distances

Do seedless vascular plants produce seeds?

No, they reproduce with spores

Which generation is dominant?

Sporophyte

Give examples of seedless vascular plants.

Ferns, horsetails, club mosses

What is the major evolutionary benefit of seeds?

Seeds protect the embryo and allow it to survive harsh conditions

What are the two groups of seeded vascular plants?

Gymnosperms and Angiosperms

What does "gymnosperm" mean?

"Naked seed" – seeds are not enclosed in fruit

Do gymnosperms produce flowers?

No

What are angiosperms?

Flowering plants that produce seeds enclosed in fruit

Why are angiosperms the most diverse plant group?

Their flowers and fruits improve reproductive success and seed dispersal

What environment do chytrids live in?

Aquatic or moist environments

What is unique about chytrid spores?

They are flagellated (motile)

What is a key feature of zygomycetes?

Produce zygospores during sexual reproduction

Give an example of a zygomycete.

Black bread mold (Rhizopus)

What is the main role of glomeromycetes?

Form arbuscular mycorrhizae with plant roots

Why are they ecologically important?

Help plants absorb nutrients and water from the soil

How do ascomycetes reproduce?

They form spores in sac-like structures called asci

Give examples of ascomycetes.

Yeast, morels, truffles

What is a lichen?

A mutualistic relationship between fungi and algae or cyanobacteria

What do lichens do in ecosystems?

Break down rocks and start primary succession

What structure do basidiomycetes use for spore production?

Basidia (club-shaped cells)

Give examples of basidiomycetes.

Mushrooms, puffballs, shelf fungi

Gametangia

organ or cell in which gametes are produced

Embryophytes

Allowed to develop and be nourished while attached to the parent plant

Pollen Grains

undergoes mitosis to make a sperm, tissue mature into seeds

Sporangia

enclosed structures in which spores are formed

Spore

unit of sexual reproduction

Lichin

can withstand severe droughts and help form soil

Roots

anchor plants to soil, conduit for water and minerals to enter

Stem

transport material from stem to leaves

Leaves

collect sunlight, gas exchange

Sporangium Formation

Chemical layer that coats spores/pollen