1. Examine examples of gymnosperm cones (microstrobili and megastrobili) available in the laboratory. Note the scale-like sporophylls and, on megasporophylls, note the depressions where seeds were previously located. Sketch one of these cones and label a megasporophyll.
2. Examine a slide of a Pinus (pine) megastrobilus (ovulate cone) using a compound microscope. Draw one megasporophyll, 2 bearing an ovule. Label the nucellus, the integument, and the micropyle of that ovule. Here is an image showing the development from ovule to seed
3. Examine a slide of a Pinus microstrobilus (staminate cone) using a compound microscope. Draw one microsporophyll bearing a microsporangium. Find and label the pollen grains contained within the microsporangium. Notice the two "bladders" or "wings" present on each pollen grain. These aid in the wind dispersal of these pollen grains.
4. Study the model of a flower available in the laboratory to find the sepals, petals, stamens, and pistil. Compare this to the live flowers (e.g. Alstromeria or Lilium) also available. Remember, few flowers will be as simple in appearance as the idealized flower model. Here are an overview of angiosperm reproduction and the development of male and female gametophytes.
5. Obtain a slide containing a cross-section through an anther carrying mature pollen grains. Draw one lobe of the anther (one microsporangium), labeling the microsporangial wall and the pollen grains. The external layer of each pollen grain is an ornate layer, called an exine.
6. Obtain a slide of germinating pollen grains. Draw one of these labeling the pollen grain and pollen tube. Examine a pollen tube carefully to find, draw, and label two dark-red staining sperm.
7. Examine a slide of a cross-section through a Lilium ovary. Draw the ovary labeling the ovary wall and the ovules. Draw a single ovule at higher magnification and label its funiculus, integuments, and nucellus. Some of these ovules have already begun the process of megaspore and megagametophyte development.
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