Academic standards correlations on Teachers' Domain use the Achievement Standards Network (ASN) database of state and national standards, provided to NSDL projects courtesy of JES & Co.
We assign reference terms to each statement within a standards document and to each media resource, and correlations are based upon matches of these terms for a given grade band. If a particular standards document of interest to you is not displayed yet, it most likely has not yet been processed by ASN or by Teachers' Domain. We will be adding social studies and arts correlations over the coming year, and also will be increasing the specificity of alignment.
In this activity, students explore the various ways in which organisms reproduce. Students discuss the role reproduction plays in the cycle of life. They observe that no individual organism lives forever and that, to carry on their species, organisms must pass their genetic instructions on to the next generation. They learn that single-celled organisms reproduce asexually, by dividing and producing two identical copies of themselves. They learn that many plants reproduce sexually, often using complex strategies that have evolved over millions of years. Finally, they explore the pros and cons of asexual and sexual reproduction and the reasons both strategies persist.
1. Begin the lesson by explaining that all living things have the following characteristics in common: they're made of cells, they use energy, they grow and develop, and they respond to their surroundings. Then ask students to name one other characteristic that all organisms have in common. (All organisms reproduce, for example.) Following this brainstorm, focus the rest of the discussion on reproduction, reminding students that one of the most important things an organism can do is reproduce. Ask:
2. Show the Single-Celled Organisms video and discuss the following:
3. Show the Floral Arrangements video and discuss the following:
4. Ask students to explore the The Mating Game Web activity in pairs. Recommend that students play two rounds of the game and then choose four of the species highlighted in the activity's Dating and Mating Gallery. Ask students to take notes on the information provided about each species, focusing on the reproductive similarities and differences among them. Have pairs of students present their findings to the class while you record the various reproductive strategies on the board.
5. Ask the class to rank the reproductive strategies on the board in order of relative difficulty, or "expense," to the animal. For example, the tube sponge's strategy of casting out clouds of sperm or egg cells into the open water is relatively less expensive than the bowerbird's efforts to attract a mate by building an elaborate bower. Ask students:
6. Show the Asexual Reproducers video and discuss the following:
7. Ask students to consider why some species might have evolved reproductive strategies that require a lot of energy and that allow individual organisms to pass only half of their genes on to their offspring. Ask students what benefits they think sexual selection might have.
8. Show the The Red Queen video and discuss the following:
Ask students to consider under what conditions each type of reproduction -- asexual and sexual -- might be the most effective strategy for passing on one's genes and avoiding extinction.