Sun Jul 12 02:24:56 2020 in Vancouver
Biology 337: Divisions
Taken Spring 2005, with Dr. Plant. Information here is based primarily upon notes from class but some from external sources like the web.
no true leaves. Thallus looks like leaves. Upper layers of Thallus contain chloroplants and pores.
Unisexual gametophytes dominates life-cycle.
Antheridia are embedded at in an elevated structure called antheridiopore which also serves as a splash cup to distribute biflagellated sperm.
Archegoniophore are located in similar elevated umbrella-like structures but archegonium are found on the underside of head. The archegonium is similar to most others in which there is a venter that contains the egg and an extended neck that sperm swim into to reach the egg.
After fertilization, the embryo will grow within the archegonium and the venter will enlarge and become a calyptra.
The embryo will develop into a structure which contains a foot that attaches it to the the gametangia via a stalk-like seta. The spores are contained within a capsule called a sporangium.
Within the sporangium there will be spores and elaters. Elaters will behave
like springs upon dihissing and eject spores into the air.
Asexual reproduction is possible too via fragmentation or gemma cups.
Nonvascular Seedless Plants
Marchantia Life Cycle
Handy quick reference
Lower surface of Thallus has rhizoids and scales which are not used for nutrient and resource acquisition but attachment.
None. H20, CO2 absorbed across surface
Copyright 2005 by Aki Mimoto (amimoto+discontinu[at]gmail.com).
Some rights reserved.
Hosting courtesy of