3) Class Anthocerotopsida (Hornworts) *Anthoceros*

Question 1

1) Four features of Anthoceros?

Answer 1

1. Multi-lobed gametophyte grows on moist soils.
2. Lacks internal differentiation except for ventral mucilage chambers.
3. Cells contain single, massive plastids.
4. Unisexual or bisexual.

Question 2

2) Location of archegonia & antheridia?

Answer 2

• Embedded within the dorsal tissues of thallus.
• Antheridia are yellow-orange at maturity, in cavities.

Question 3

3) Fertilization & development [5 points]?

Answer 3

1. Fertilization produces many chlorophyllous, needle-like sporophytes.
2. Meristematic tissue between foot and sporophyte leads to continuing development.
3. Spores are produced over several months & are shed at the apex.
4. Stomata and guard cells are present on epidermal cells of sporophyte.
5. Spores give rise to new gametophytes.