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Diversity - Non-vascular Plants

	Which bacteria share some features with plants?
	The cyanobacteria (blue-green algae) are photosynthetic.

	What kinds of bacteria are important economically and for plant life?
	soil bacteria, particularly N fixing and nitrifying bacteria and bacterial plant diseases

	What makes fungi different from plants?
	Fungi are non-photosynthetic, have chitin cell walls and coenocytic cell structure.

	What kinds of fungi are important economically and for plant life?
	mushrooms, mycorrhizae and fungal plant diseases

What are plant-like and non-plant-like features of euglenoids, diatoms, green algae and brown algae?

euglenoids (Euglenophyta) photosynthetic pigments - chlorophyll a & b, carotene food reserve - paramylon cell wall - none (mostly a protein pellicle) green algae (Chlorophyta) photosynthetic pigments - chlorophyll a & b, carotene food reserve - starch cell wall - sometimes cellulose diatoms (Chrysophyta) photosynthetic pigments - chlorophyll c, fucoxanthin food reserve - chrysolaminarin cell wall - silica brown algae (Phaeophyta) photosynthetic pigments - chorophyll c, fucoxanthin food reserve - laminarin cell wall - cellulose & alginic acid

	Where are we likely to encounter algae and what is their economic importance?
	as "weeds" growing on damp walls, tree trunks, soil surface and in irrigation ponds and pipes also sea-weed derived fertilizers, food gels and agar (and Chinese restaurants)

	What are the differences between the pores in a liverwort and stomata in a higher plant?
	Pores are multicellular and cannot open and close like stomata.

	Which functions of roots do rhizoids fulfill for the liverwort?
	anchorage only

	How do liverworts propagate themselves?
	vegetatively by spread of thallus and sometimes by tiny propagules (gemmae)

	What kind of habitat do liverworts occupy and how does this relate to their structure?
	They are confined to a permanently wet habitat (no cuticle, open pores and no roots).

	What is the ploidy level of the leafy plant?
	haploid

	What gives rise to a sporophyte and what does it look like?
	Sperm fertilizes an egg to produce a zygote. The Stalk grows out of the tip of the gametophyte with the sporangium on top.

	Where does meiosis occur and to what does it give rise?
	inside sporangium to produce spores

	Where does some kind of conducting tissue occur and what is it like?
	In the stem of gametophyte and sporophyte elongated cells (leptoids and hydroids)

	Where are we likely to find this kind of plant?
	in damp or shady places

	How does its structure and life cycle determine its habitat?
	no roots or proper conducting tissue needs water for sperm to swim

	When we find these plants growing on damp soil and rocks are we looking at the: gametophyte sporophyte archegonium
	Yes, unlike most other plants, the dominant phase of the life-cycle is the gametophyte.   Apart from the Hepaticophyta and Bryophyta, the gametophyte is pretty inconspicuous throughout the remainder of the plant kingdom.   You can sometimes see archegoniophores (structures bearing archegonia) but this is not the main part of the plant.

	So what is its level of ploidy: 2n 1n 4n
	No, gametes are haploid so the plant that produces them should be similar.   Yes, as you would expect from its name it is haploid.   There is no tetraploid stage in the life-cycle.

	How does the liverwort take up water: through rhizoids through the thallus through pores
	Perhaps a little, but these single celled hairs mostly just hold the plant down   Yes, liverworts take up (and lose) water over pretty much their entire surface.   The pores have more to do with gas exchange, and they may even let water escape under dry conditions

	Where would you expect to find liverworts growing: only in the tropics on exposed mountain-tops in damp-shady places
	They are quite cold-hardy, and can certainly survive Ohio winters   Although they are cold-hardy they cannot withstand drying winds that would be likely to occur on mountain tops.   Yes, they can be found growing in all sorts of places as long as they are damp and shady: rocks, patios, plant containers etc.

	What does the moss have that is missing from thalloid liverworts: roots stem xylem
	The moss only has rhizoids, just like the liverwort   Yes, unlike many liverworts, mosses are usually differentiated into leaves and stems.   Mosses have poorly differentiated conducting tissue (hydroids and leptoids) but no true xylem.

	What stage of the lifecycle is the leafy moss plant: gametophyte sporophyte antheridia
	Yes, as with the liverwort, the gametophyte is the dominant phase of the life-cycle.   This would be true for most other plants, but not in the case of the moss.   Antheridia may be present but they are invisible to the naked eye and ceratinly not the whole of the plant.

	If it is the male gametophyte what structures should be present at maturity: antheridia sporangia archegonia
	Yes, antheridia are formed on the male gametophyte   Sporangia are formed on the sporophyte (on the moss and throughout the plant kingdom)   Archegonia are formed on the female gametophyte.

	What is formed by the antheridia: pollen spores sperm
	Pollen is a kind of spore produced by the sporophyte of higher plants   Spores are released by the sporophyte   Yes, whenever antheridia are formed they produce sperm cells.

	How do the sperm cells get to the egg? swim through water carried by the wind carried by animals
	Moss sperm have flagellae that enable them to swim to the egg. Rain drops can also help to move them around.   Not in this plant or any other (sperm are very delicate)   In flowering plants we will see insects and other animals carrying pollen, but the process is much more hapazard for moss sperm

	So where is the egg cell: also swimming around next to the antheridium on another gametophyte
	No the egg cell is always stationary (throughout the plant kingdom). In the moss each egg is inside an archegonium.   No, the moss gametophyte is unisexual   Yes each egg is in an archegonium at the tip of the female gametophyte.

	So the sperm finds an egg, fertilization occurs and a zygote is formed. What next? meiosis mitosis spore formation
	Not just yet - the life cycle is more complex   Yes while it is still in the archegonium and at the tip of the female gametophyte a new plant, the sporophyte, starts to grow.   Not just yet - but we are on our way to spores

	What is the ploidy level of the sporophyte? 1n 2n 4n
	The sporophyte grew out of a zygote formed by the fusion of two (haploid) gametes.   Yes a mature female moss plant consists of a diploid sporophyte growing out of a haploid gametophyte.   There is no tetraploid phase in the life cycle

	How many cells are formed from the spore-mother cells in the sporophyte? 2 4 8
	These cells undergo meiosis, so how many cells are normally formed in this process?   Yes since this is where meiosis occurs, four cells are produced. The cluster of four is often called a tetrad.   These cells undergo meiosis, so how many cells are normally formed in this process?

	After dispersal what does a spore produce: a sporophyte a protonema a gametophyte
	Spores come from a sporophyte, but they grow into something else.   Yes a spore germinates to form a filamentous protonema that does not survive. It produces buds from which new gametophytes (all male or all female) grow out to start the alternation of generations over.   In a sense, although the plants that we recognize as gametophytes grow out of something else.

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