. Biology; the story of living things. Wriilhl I'Urcc Tiger Swallow-tail (Papilio turnns) on rose. The Relations between Insects and Flowers One of the most interesting symbiotic relationships is that which exists between msects and flowers. Flowering plants produce . and fruits, and from these come new gen- erations of plants, but if it were not for the visits of insects, many plants would not produce seeds. Insects visit flowers in order to obtain nectar, a sugary sub- stance formed by the nectar glands, and pollen. The glands which produce the nectar are usually so placed that an inse
. Biology; the story of living things. Wriilhl I'Urcc Tiger Swallow-tail (Papilio turnns) on rose. The Relations between Insects and Flowers One of the most interesting symbiotic relationships is that which exists between msects and flowers. Flowering plants produce . and fruits, and from these come new gen- erations of plants, but if it were not for the visits of insects, many plants would not produce seeds. Insects visit flowers in order to obtain nectar, a sugary sub- stance formed by the nectar glands, and pollen. The glands which produce the nectar are usually so placed that an insect has to push its way past the stamens and pistil of the flower in order to reach the desired food. In doing this, pollen grains may adhere to the hairy covering of the insect and be transferred to the sticky surface of the upper end of the pistil (stigma). Inside the pollen grains are the male re- productive cells (sperms), while in the ovary of the pistil are held the female reproductive cells (eggs). In order to ha\e develop- ment of a new plant, it is essen- tial for a sperm cell to unite with an egg cell. Pollen grains on the stigma are stimulated to send out hairlike tubes, wiiich j)enetrate the stalk (style) of the j)istil and eventually reach the ovary. The pollen tube carries one or more •derminatino: anther* •filameriti ovulell''. .-finicropyle-' A longitudinal section of the repro- ductive organs of a flower showing the penetration of a pollen tube through the opening in the pistil called the micropyle, and the growth of the pollen tube to the 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 the original Hunter, George W. (George William), 1873-1948; Walter, Herbert Eugene, b. 1867; Hunter, George W. (George William), 1902-. New York, Cincinnati [etc. ] American book company
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Keywords: ., bookauthorwalterherberteugeneb1867, bookcentury1900, bookpublish
