. Adventures with animals and plants. Biology. PROBLEM 3. How Co?nplex Flants seeds are formed. Finally, they dis- covered that reproduction in seed plants is in many respects like reproduction in complex animals. The embryo you found in the seed grows from a fertilized egg- cell which is formed by the union of two dissimilar gametes. The gametes, as in animals, are sperms and eggs. But be- yond this we must not expect to find much similarity since plants and animals are so different in structure. The plant does not hav^e organs corresponding ex- actly to the spermaries and ovaries of an anima
. Adventures with animals and plants. Biology. PROBLEM 3. How Co?nplex Flants seeds are formed. Finally, they dis- covered that reproduction in seed plants is in many respects like reproduction in complex animals. The embryo you found in the seed grows from a fertilized egg- cell which is formed by the union of two dissimilar gametes. The gametes, as in animals, are sperms and eggs. But be- yond this we must not expect to find much similarity since plants and animals are so different in structure. The plant does not hav^e organs corresponding ex- actly to the spermaries and ovaries of an animal. Where are the sperms and eggs produced in plants? To answer this we must examine the blossom or flower. The flower. Let us find out how a flower is constructed so that we may find the gametes and learn how the seeds are made. Tulips, lilies, or sweet peas are Reproduce 439 large and easy to study. See Exercise 3. The tulip has six brightly colored or white leaflike parts. They are arranged in an outer circle and an inner circle, each consisting of three parts. In many flowers the outer circle (calyx) is green and the parts are known as sepals. The inner circle (corolla) consists of bright petals which often are larger than the sepals. Inside the floral envelope is a circle of stamens (stay'mens). Each stamen consists of a threadlike part with a knob on the free end. In the very center of the blossom is a single pistil. The number, shape, size, and color of all flower parts are different in different kinds of plants. Often it is these differences which are used in classifying the plant. Flower parts used in reproduction. It is the stamens and pistils that are used in. Stamen^ Pistil Ovary l|^ Anther (enlarged) (enlarged) f-J^ Fig. 387 The flower parts of a lily. Two of the leaflike parts have been cut away. How ?many of each of the flower parts were there? Study the sta?nen and Please note that these images are extracted from scanned page images that may have b
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