. Adventures with animals and plants. Biology. PROBLEM 3. How Complex Plants scatterinor the seeds over a wide area. The outside agents that help in this seed dispersal are wind, water, birds, and other animals, including man. You prob- ably can give numerous examples of seed dispersal. Do Exercise io. The life cycle of the flowering plant. At certain times the flowering plant pro- duces flowers containing stamens and pistils. The stamens produce pollen grains which later produce sperms in the pollen tube. The ovary contains ovules each of which forms an egg in the embryo sac. Fertilization oc
. Adventures with animals and plants. Biology. PROBLEM 3. How Complex Plants scatterinor the seeds over a wide area. The outside agents that help in this seed dispersal are wind, water, birds, and other animals, including man. You prob- ably can give numerous examples of seed dispersal. Do Exercise io. The life cycle of the flowering plant. At certain times the flowering plant pro- duces flowers containing stamens and pistils. The stamens produce pollen grains which later produce sperms in the pollen tube. The ovary contains ovules each of which forms an egg in the embryo sac. Fertilization occurs within the embryo sac after pollination and the growth of the pollen tube. The fertilized egg cell then develops into the embryo. The ovule which contains the fertilized egg grows into the seed. The ovary grows into the fruit. During the growth of the ovary into a fruit the petals wither and usually fall off. Gradually the fruit and the seeds within it ripen on the plant. The ripe seeds later drop to the ground, sometimes while still in the fruit. There they may rest over the winter. When conditions are favorable, the embryo within the seed bursts through the seed coats and grows into the seedling and gradually comes to look like the parent plant. In time this plant again bears flowers and the cycle is repeated. The organs which have been concerned in one way or another with reproduction are the flower, fruit, and seed. (Optional) Reproduction in ferns. Ferns never bear blossoms. They pro- duce spores by asexual reproduction. At certain seasons the spore cases show clearly on the lower surface of the frond (leaf). See Figure 364. When the spores ripen, they fall out of the cases and are Reproduce Fu;. 395 Fruits and seeds. How may each kind be dispersed? MILKWEED. BURDOCK. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble th
Size: 1581px × 1581px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookpublisherbostondcheath, booksubjectbiology
