Among "fungi" you have seen three different life histories. Name the three types of life history, tell briefly the fundamental differences, and give an example "fungus" for each life history. 12 points.
Life History Gametophyte Sporophyte Example spor-ic multicellular multicellular Allomyces gamet-ic spore-->gamete multicellular Saprolegnia zygot-ic multicellular zygote-->sporocyte Mucor
In studying the fungal-like organisms, you studied a table of six divisions (phyla) of organisms. Name the divisions and tell what distinguishes each division from the others. 12 points.
Division (Phylum) Distinguishing Feature(s) Myxomycota plasmodium Chytridoomycota haustorium Oomycota oogonium Zygomycota zygospore Ascomycota ascus Basidiomycota basidium
You are on a trip to Bermuda and you are observing a particular species of Rhodophyte algae. While examining its distribution from the high-tide (exposed at low tide) mark to a depth of 30 meters on the flanks of the seamount, you collect specimens into netted bags and bring them to shore, making careful note of the depth at which each is collected. The specimens are one of three different colors (green, red, bluish-purple) depending upon the depth at which the alga was growing. Tell which colors are associated with each depth and explain why/how the colors change with depth. Hint: water is fairly transparent, but selectively absorbs lower-energy wavelenths. 12 points.
depth exposed at low tide continuous shallow in deep water algae
green blue-purple red why/how There is plenty of 680/700 nm light, no critical accessory pigments are made 680/700 nm light absorbed by water, phycocyanin and phycoerythrin made to use yellow/orange and blue/purple for PSN Even yellow/orange absorbed by water, phycoerythrin made to use blue/purple for PSN
On this page, diagram the life cycle of a mushroom. Be sure to show all of the various parts of the life cycle, including reasonably-large sketches of microscopic stages. All parts of each sketch must be fully labeled. It is important to indicate processes on any arrows connecting sketches. It is important to show the chromosome condition (1N, 2N, etc.) for each sketch as well! 27 points.
basidiospore nDefend the gamete condition you have assigned based on your sketches above: 2 points.
+/- mating types
isogamous-fusing cells are the same sizeDefend the life history type you have assigned in your sketches above: 3 points.
sporic-dikaryotic mycelium is sporophyteHow many spores are produced from one plasmogamy event in mushrooms? 1 point
zygotic-only truly diploid in basidium (zygote become sporophyte)
indefinitely manyHow many spores are produced from one karyogamy event in mushrooms? 1 point
4Simple Green Algae
+/- mating types
Chlamydomonas braunii is just like C. reinhardtii, except for the fact that it is anisogamous. Redraw whatever sketch(es) must be revised in the life cycle. 4 points|
both motile; female large, male small
Chlamydomonas coccifera is just like C. reinhardtii, except for the fact that it is oogamous. Redraw whatever sketch(es) must be revised in the life cycle.|
female = large, immotile; male = small, motile
Complex Green Algae
Not all algae are as simple as Chlamydomonas. Perhaps a more typical example is the common sea lettuce, Ulva lactuca. Sea lettuce is commonly observed in the wrack on the beach, but it is found naturally anchored in shallow tide pools. It is anisogamous, sporic, heterothallic and completely isomorphic. Gametes are biflagellate; two fundamentally-different motile cells in the sexual cycle are quadriflagellate. Assume there is no asexual reproduction. Using this information, sketch and label the life cycle of Ulva lactuca below. 19 points.
biflagellate female gamete
biflagellate male gamete
In the following grid, make and label a sketch of each part of the life history of a moss. 25 points total.
|spore 2 points|
|zygote 2 points
|gametophyte 3 points|
|sporophyte 3 points|
|gametangia 9 points|
neck canal cells
|sporangium 6 points|
|What stage of the life history of a moss indicates an alga-like ancestor?||protonema|
|What characteristic of gametangia and sporangia in mosses shows good adaptation to life on land?||sterile jacket|
|What characteristic of moss gametophytes is adaptive for terrestrial existence?||hydroids and leptoids|
|What characteristic of moss sporophytes is adaptive for terrestrial existence?||cutin and stomata|
|What structural characteristic of moss spores is adaptive for terrestrial existence?||sporopollenin and wind dispersal|
|What characteristic of hornwort sporophytes expands their reproductive potential?||intercalary meristem|
|What characteritic of hornwort sporophytes is most-adaptive for independence from the gametophyte?||photosynthesis|
|What is the gamete condition found in all true plants (bryophytes and vascular plants)?||oogamous|
|What is the kind of life history found in all true plants (bryophytes and vascular plants)?||sporic|
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