Bryophytes

in plants, a complete life cycle involving sexual reproduction has an alteration of generations between a _________ phase and a __________ phase

diploid sporophyte and haploid gametophyte

what is a sporophyte?

spore-producting plant (2n)

what is a gametophyte?

gamete-producing place (n)

what is the major event where a multicellular sporophyte (2n) divides into two haploid spores?

meiosis

what is the major event where a sperm cell and egg cell that are both haploid come together to form a diploid zygote?

fertilization

in most bryophytes, such as mosses: sporophytes are ________ and gametophytes are ________.

dependent; independent 

in most seedless vascular plants, such as ferns: sporophytes are __________ and gametophytes are _________.

independent; independent 

in gymnosperms, such as conifers: sporophytes are _________ and gametophytes are ________

independent; dependent 

in angiosperms (flowering plants): sporophytes are _________ and gametophytes are _______

independent; dependent

the zygote, sporophyte, sporocyte can all be described as _____ cells

diploid 

the gametes, gametophyte, and spore can all be described as _____ cells

haploid

change from sporophyte to gametophyte generation usually occurs as a result of ________.

meiosis

change from gametophyte to sporophyte usually occurs as a result of ________

fertilization

how many species of broyphtes are there?

about 23,000

what types of plants are included in the category bryophyte?

mosses, liverworts, hornworts

what is the habitat range for bryophytes?

habitats range in elevation from sea level up to 5,500 m or more

how long have bryophytes been around?

they are among the first land plants and have existed more than 400 million years ago 

bryophytes of all phyla often have what features?

mycorrhizal fungi associated with their rhizoids 

T or F: bryophytes have vascular tissues

False; none have true xylem or phloem

how do bryophytes get water to their cells?

hydroids: water-conducting cells

• many have these 

how do bryophyes get food to their cells?

leptoids: food-conducting cells 

• few have these 

bryophytes exhibit an alteration of __________

generations

which adult generation is dominant for bryophytes?

gametophyte 

what is the scientific name for peat mosses?

Sphagnum

peat mosses are ecologically important in _____

bogs

• carbon storage

how old was the man found preserved in peat mosses in Denmark?

2,400 years old

what phylum are liverworts a part of?

Hepaticophyta

describe the structure liverworts

most common liverworts have flattened, lobed thalli (thallus) 

what is the function of the thalli in liverworts?

during the gametophyte stage is develops from spores 

when the spores of liverworts germinate they produce immature gametophyes which are called:

protonema

the best known species of thalloid liverworts are in the genus: 

Marchantia 

what is the structure of Marchantia?

thick thallus that forks dichotomously as it grows 

• consists of parenchyma cells with few if any, chloroplasts

gametophytes are unisexual in:

Marchantia

what are gametangia?

gamete producing structures

in male the gametangia is called:

antheridia

in females the gametangia is called:

archegonia

how do the marchantia reproduce asexually?

by the production of gemmae (gemma, ‘bud’)

what are the structures and functions of gemmae?

tiny, lens-shaped tissues that detached from the thallus 

give rise to new gametophytes 

how are gemmae dispersed?

fly off and are carried by the wind

the gemmae of Marchantia, thauus are contained in the __________

gemma cups 

what structures does the sporophyte in Marchantia consist of?

a foot, a short seta (stalk), and a capsule (sporangia) 

what is the function of the foot of the sporophyte in marchantia?

the foot anchors the sporophytes

where are the sporocytes contained in the sporophye structure?

in the capsule

what happens do the sporocytes in the capsule of a Marchantia?

they undergo meiosis, producting haploid spores 

is the foot of the sporocyte in Marchantia haploid or diploid?

diploid

is the seta of the sporocyte in Marchantia haploid or diploid?

diploid

is the elater of the sporocyte in Marchantia haploid or diploid?

diploid

is the capsule of the sporocyte in Marchantia haploid or diploid?

diploid

is the calyptra of the sporocyte in Marchantia haploid or diploid?

haploid

are the spores of the sporocyte in Marchantia haploid or diploid?

haploid

what is the function of the elater?

to twish and help release spores from the capsule thus facilitate the spread of spores

what is a major difference b/w antheridium and archengonia?

there are TONS of sperm cells w/n the aneridium, but only one egg cell w/n the archegonia

what is key to the life cycle of Marchantia?

water/moisure needed so that sperm can move to the egg

what phylum are Hornworts in?

Anthocerophyta

mature sporophytes of hornworts look like what?

miniature greenish-blackish rods

there are only about ____ species of hornworts worldwide

100

describe the structure of halli of hornworts

they have pores and cavites filled with mucilage, that often contain nitrogen-fixing bacteria 

what does asexual reproduction consist of in Hornworts?

fragmentation

separation of lobes from thallus

what does sexual reproduction consist of in Hornworts?

archegonia and antheridia are produced in rows beneath the upper surface of the gametophytes 

• have both unisexual and bisexual plants

there are about _____ species of mosses

9,500

mosses are in the phylum:

Bryophyta

Mosses are divided into three classes, these are:

• peat mosses 

• true mosses 

• granite mosses 

the “leaves” of moss gametophytes have no what?

mesophyll tissue, stomata, or veins

what are the blades like in mosses?

blades are nearly always one-cell thickm and are never lobed or divided

the moss sporophyte consists of what structures

a capsule (with a lid, operculum) and a seta

in mosses, sexual reproduction begins with the formation of ________ at the tips of the leafy gametophytes

gametangia

what is the human and ecological relevance of phylum bryophyta?

pioneer species of primary succession 

indicators of surface water 

packing material 

peat mosses 

• soil conditioner 

• poultice material 

• fuel