Lab 4 Review: Bryophytes & Seedless Vascular

Bryophytes include

• mosses

• liverworts

• hornworts

Bryophyte adaptations for terrestrial life

1) cuticle: sterile jack layer around reproductive structures

2) antheridia/archegonia: embryo protected from desiccation (drying out)
3) Spores can go dormant

Do Bryophytes have vascular tissues (xylem/phloem)?

No

What do bryophytes have in place of leaves and stems?

rhizoids and a thallus

In haplodiplontic life cycles, what is the dominant 1N generation called?

Gametophyte

In haplodiplontic life cycles, what is the dominant 2N generation called?

Sporophyte

Liverworts adaptations

• cutinized surface = reduced water loss

  • open pores (can NOT close) on thallus = gas exchange

Liverwort reproduction

Asexual

• gemmae cups

Identify the reproductions structures on liverwort 

A) Gemma 

B) Splash cup 

C) Gametophyte thallus

Define dioecious

(“two houses”) Male and female parts exist on different plants

Archegonium

Female structure: contains 1 egg

Antheridium

Male reproductive structure: contain swimming sperm 

Identify the depicted structure

Archegonia

Identify the structure

Antheridia

True mosses adaptations

• stomata on sporophyte (not gametophyte) = generally stay open

• Conducting cells (growing vertically)

Which generation is dominant in true mosses

gametophyte

Ecological roles of Bryophyta

• freezing and desiccation in harsh conditions

• carbon sink - add living carbon to soil

• pioneer species - stabilize soil and reduce erosion

some hornworts have:

• stomata

• cutin

• nostoc

Hornworts dominant generation

sporophyte (2n)

Derived traits of seedless vascular plants

• stems, roots, leaves 

• dominant sporophyte

• vascular tissue

What kind of environment do seedless vascular plants thrive in?

Wet environment (swimming sperm)

Club mosses are NOT

true moss

Characteristics of club mosses

• microphylls (“leaves”)

• rhizomes (not roots)

• asexual AND sexual reproduction

• some heterospores

Identify the organism and the structures of this depicted

Club moss
a) spore

b) sporophyll

c) sporangium

What genus is the only one found among horsetails? 

Equisetum

What type of rhizomes do horsetails have?

horizontal

What is special about the stems of horsetails?

They’re photosynthetic

What are elators?

Surface extensions on the spores of horsetails that move in response to humidity

What do the epidermal cells of horsetails contain?

silica (good scrubbers)

Identify the organism and the structures depicted

Horsetail
a) rhizome

b) strobilus 

c) stem

Where are the sporangia located on horsetails?

sporangiosphores located in strobilus

Dominant generation in ferns

sporophyte

Adaptations in the ferns:

• vascular tissues (xylem/phloem)

• stomata on leaves

• lignin in cell walls

Identify the organism and the structures indicated

Fern

a) leaflet/pinnule

b) frond

c) fiddlehead

What are the frond spores called and where are they located?

sori; underside of fronds

Identify the parts of the fern within its life cycle

a) frond

b) leaflet/pinnae

c) sori

d) rhizome

e) archegonia 

f) antheridia

g) fiddlehead