Presentation on theme: "IMPORTANT ANNOUNCEMENT The Tuesday and Wednesday lab sections will have a lab quiz next week The Thursday lab section (this section) will not have a lab."— Presentation transcript:
IMPORTANT ANNOUNCEMENT The Tuesday and Wednesday lab sections will have a lab quiz next week The Thursday lab section (this section) will not have a lab quiz next week. People from the Tuesday and Wednesday lab sections are being required to take the lab quiz with the lab section they are registered for. If they attend lab on Thursday to avoid the lab quiz, they will receive a zero on the lab quiz. There is an announcement to this effect on the main course web page ( @ bioweb.html ).
Phylum Hepatophyta Thallose Liverworts Marchantia Sporophyte sporangium wall meiospores (n) and elaters (2n) calyptra seta or stalk foot photo by Ross Clark
Phylum Hepatophyta Leafy Liverworts Frullania gametophytes photo by Ross Clark One of the obvious differences between leafy liverworts and mosses is that the leaves of leafy liverworts have dorsal and ventral lobes. The smaller ventral lobes are underneath the dorsal lobes, when you view the liverwort from above. dorsal lobe ventral lobe
Moss protonemata (Phylum Bryophyta) Note the leafy moss gametophytes growing from the alga-like protonemata. photo by Ross Clark
Phylum Bryophyta Mosses protonema This is from a prepared slide. Protonemata are normally bright green.
Phylum Bryophyta Mosses Gametophytes and Sporophytes (= sporangium; 2n) (= stalk; 2n) Note: Mosses do not have microphylls, because there is no vascular tissue. calyptra (covering the capsule)
Phylum Bryophyta Hairycap moss (Polytrichum) Note: gametophytes (n) stalks (setae) – 2n sporangia (capsules) – 2n photo by Ross Clark
Phylum Bryophyta Mosses Mnium (= a moss genus) antheridia This is the top of a male gametophyte. antheridia paraphyses = sterile structures which help to preserve the film of water antheridial head leaves All of these structures are haploid.
Phylum Bryophyta Mosses Mnium archegonia venter with egg within neck and neck canal paraphyses All of these structures are haploid.
Phylum Bryophyta Mosses Polytrichum capsule (= sporangium) operculum (= cap) peristome columella spores a very well-worn capsule! (probably more than a year old) operculum greenish-yellow material consists of the spores
Not a moss?!? Hey!... It’s Spanish Moss, a flowering plant (a bromeliad) Spanish “moss” isn’t a moss, because it has flowers, fruits and seeds. That stuff that gets caught on your fishhooks isn’t moss, either. These are true leaves! (megaphylls)