Moss

Question 1

Bryophyte Evolution

Answer 1

The diverse bryophytes are not a monophyletic (linear) group.

These three phyla diverged independently early in plant evolution, before the origin of vascular plants.

Liverworts and hornworts may be the most reasonable models of what early plants were like.

Mosses are the bryophytes most closely related to vascular plants.

Probably Earth’s only plants for the first 100 million years that terrestrial communities existed.

Question 2

Reproduction

Answer 2

The gametophyte consists of gamete-producing structures, the gametophores and root-hair like rhizoids.

Gametophores are haploid (n), photosynthetic and gamete producing.

Gametes are produced in gametangia:
Each vase-shaped archegonium produces a single egg.
Elongate antheridia produce many flagellated sperm.

*In bryophytes, gametophytes are the most conspicuous, dominant phase of the life cycle.

*Sporophytes are smaller and are present only part of the year.

*Bryophyte spores are homosporous (all spores the same size)

*Spores germinate in favourable habitats and grow by mitosis into masses of green, branched, one-cell-thick filaments, called a protonemata

Question 3

Reproduction (cont’d): Fertilization

Answer 3

When plants are coated with a thin film of water, flagellate sperm swim toward the archegonia, drawn by chemical attractants.

They swim into the archegonia and fertilize the eggs.

The zygotes and young sporophytes are retained and nourished by the parent gametophyte.

Layers of placental nutritive cells transport materials from parent to embryos.

Question 4

Liverworts

Answer 4

Question 5

Rhizoid

Answer 5

Question 6

Leaves

Answer 6

Question 7

Cells

Answer 7

Question 8

Stems

Answer 8

Question 9

Liverwort and hornwort

Answer 9

Question 10

‘leaves’ and ‘stems’

Answer 10

Question 11

Growth Habits

Answer 11

Question 12

General morphological features

Answer 12

Question 13

Sporophytes

Answer 13

Question 14

Sporangium

Answer 14

Question 15

Hair-cap moss

Answer 15

Question 16

Sphagnum moss

Answer 16

Question 17

Sphagnum (peat) moss

Answer 17

Question 18

Sphagnum leaf

Answer 18

Most of the plant is not alive - sits in water - anaerobic and antimicrobial

Question 19

Rithits bog restoration

Answer 19

Ducks unlimited brought in weir - water table moving up, but can’t log and remove bc of neighbours.

-want to bring in peat moss sphagnum.. Need to peat mine - don’t have soil because of all the pine needles.

Water control is good though (with weir..)

Question 20

Before and after design for Rithets bog

Answer 20

*restoration need hydrology, soils and plants

*independent study because nothing to build on..