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| What is meant by "alternation of generations"? | This is the switching back and forth between the production of diploid and haploid cells, something that most algae do. |
| Review: what are diploid cells? What are haploid cells? | Diploid= cells that contain a double set of chromosomes, one from each parent; thus, they have the full complement of chromosomes for a particular species. Haploid=cells that contain a single set of chromosomes, so they only have half the complement of a particular species. |
| Do algae reproduce sexually or asexually? | Algae reproduce both ways: sexually where gametes are produced; asexually with haploid cells called zoospores. |
| Define "isogamy". | The condition in which the gametes of an organism appear identical (2 identical reproductive cells are formed during unfavorable conditions when "Chlamydomonas" switches from asexual to sexual reproduction). |
| What is syngamy? | Syngamy is the fusing of algal gametes. See pg. 440 in text. |
| Why would algae alternate between sexual and asexual reproduction? | By being able to switch from asexual to sexual reproduction, the algae is enabled to adapt to its environment. When conditions are harsh, the algae can reproduce sexually and wait for conditions to improve so it can reproduce asexually again. |
| What is a sporaphyte? | A sporaphyte is a diploid plant that produces spores. An "Ulva" is both a sporophyte and a gametophyte. |
| What is a gametophyte? | A gametophyte is a haploid plant that produces gametes. |
| In the "Ulva", what happens when the the two different gametes it produces (heterogamy) fuse? | A diploid zygote results. It grows into a multicellular diploid sporophyte, which reproduces asexually through meiosis and releases haploid zoospores. They divide by mitosis & grow into 2 different types of gametophytes. The cycle starts again. |
| The "Fucus" algae has both alternation of generations and heterogamy. What does this mean? | "Fucus" can alternate between sexual and asexual reproduction AND also produce 2 different kind of gametes. |
| What specialized reproductive areas are found on the tips of the "Fucus" blade? | One area of the tip produces eggs; the other area produces sperm. |
| How do "Fucus" reproduce after an egg and sperm are produced? | The egg & sperm are released into the water; the eggs drift; sperm may manage to swim to an egg and fertilize it, forming a zygote. The zygote sinks; if it lands on a rock, it attaches itself and grows by mitotic division into a new diploid sporophyte. |
| Review: what is mitosis? | Mitosis is the process by which a cell's nucleus is divided into 2 nuclei; each one has the same number & kinds of chromosomes as the parent cell. |
| Why are algae important in the sea? | Algae are a vital source of food for most life in the oceans. They also provide homes for numerous animal species. |
| What important vitamin and mineral are in algae? | Vitamin C and Iron are in algae. |
| In the health industry, how are algae important? | They're used to treat stomach ulcers, lung ailments, high blood pressure, and arthritis. They're also found in toothpastes, adhesives, and hand lotions. |
| How are algae used in food products? | Algae make ice cream smooth & candy bars last longer; used in pickle relishes, salad dressings, chip dips, pancake syrups, egg nogs, & canned chow mein. Some eat algae. They're used as flavorings in soups, meat dishes, and candy. |
| How are algae important to modern industry? | Algae help make finger paints, plastics, waxes, transistors, deodorants, paints, lubricants, artificial wood; they're also in poultry feed, cake batters, pie fillers, jellies, and doughnut glazes. |
| Agar-agar, from certain seaweeds, is important in research. How? | It thickens the nutrient mixtures in which scientists grow bacteria and other microorganisms. |
