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Pollen tube Stock Photos and Images
RF2C9B8TE–An extreme close-up or macro shot with shallow depth of field and very selective focus of a red amaryllis flower in full bloom.
RM2AJBF78–Elementary botany . Fig. 393- Mature embryo sac (young pro-thallium) of lilium. m, micropylarend; 5, synergids; E, egg; P?i,polar nuclei; Ant, antipodals.(Easter lily.) Fig- 394- Section through nucellus and upper part of embryosac of cotton at time of entrance of pollen tube. E,egg; S, synergids; P, pollen tube with sperm cell inthe end. (Duggar.) GAMETOPHYTE AND SPOROPHYTE. 33 is developing it derives its nourishment from the endosperm (orin some cases perhaps from the nucellus). At the same time.
RMT1HN6A–Diseases of plants induced by Diseases of plants induced by cryptogamic parasites; introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae diseasesofplants00tube Year: 1897 258 ASCOMYCETES. coniclia germinate and give off long septate hyphae which, follow- ing the course of the pollen-tube, reach the ovary, and soon fill all four loculi with a white mycelium. The growth of this mycelium proceeds from the central axis towards the walls, and forms a hollow sphere open above and below. The diseased berries cannot be distinguished till ripe; then, whereas the normal are red
RMPG3RNF–. The elements of botany embracing organography, histology, vegetable physiology, systematic botany and economic botany ... together with a complete glossary of botanical terms. Botany. 160 SYSTEMATIC BOTANY. when fertilization is to take place, allows the entrance of the pollen-tube. i8i. Simultaneously with the growth of the integuments is developed, near the upper end of the body, or nucleus of the ovule (Fig. 276), the embryo-sac (Fig. 276, em. s). This, when first distinguishable from the other tissue, consists of a cell somewhat larger than the adjacent ones. It then enlarges greatly; vo
RMMA8429–. Elementary botany . Fig. 30 Fig. 306. Mature embryo sac (young pro- Section through nucellus and upper part of embryo thallium) of lilium. ///, micropylar sac of cotton at time of entrance of p.-lien tube. E, end; .V, synergids ; E% egg; Pn> egg: S, synergids: Pt pollen tube with sperm cell in polar nuclei; Ant, antipodals, the end. (Duggar.) (Easter liiyj
RM2CTNTJ5–The Hebe is a popular evergreen and hardy shrub native to New Zealand and South America. Gardeners favour their frost resistance
RF2C9B8NK–An extreme close-up or macro shot with shallow depth of field and very selective focus of a red amaryllis flower in full bloom.
RM2AG2PJ0–. Natural history object lessons : a manual for teachers. Fig. 65.—Pollen Grainswith. Tubes.. Fig. 66.—Tubes of Pollen Grains penetratingthe Tissue of the Stigma. active and grow. Each cell sends out a long slender tube,the pollen-tube, which slowly penetrates through the loosetissue of the stigma and through the style (when one ispresent) into the ovary. Into this pollen-tube the activevital fluid of the pollen-cell passes to the ovule, which thusbecomes fertilised. CHAPTER IX. FRUITS AND SEEDS. In the flower, as we have seen, the ovary, consisting of oneor more carpels, contains the oviiies.
RMT03RN5–Elementary botany . elementarybotany00atki Year: 1898 MORPHOLOGY. size of the female nucleus before the fusion of the two takes place. In figs. 306 and 307 are shown the entering pollen tube with the sperm nucleus, and the fusion of the male and female nuclei. 457. Fertilization in plants is fundamentally the same as in animals.—In all the great groups of plants as represented by spirogyra, oedogonium, vaucheria, peronospora, ferns, gymno- Fig. 304, Two- ami four-celled stage of embryo-sac of lilium. The middle one shows di ision nuclei to form the four-celled stage. (.Easter lily.) sperm
RMPG3RKW–. Plant life and plant uses; an elementary textbook, a foundation for the study of agriculture, domestic science or college botany. Botany. 434 THE VASCULAR PLANTS have germinated as internal parasites and thus the female gametophytes have been produced. One gametophyte matures in each megasporangium. It produces two or more eggs. (See Figure 226.) The sperms are in the pollen and the eggs are in the megasporangia. How are they to be brought together? C. The Pollen Tube. — You have learned of pollen tubes in your study of the flower. You know that they grow down through the styles, penetrate t
![. Elementary biology; an introduction to the science of life . Fig. 153. Alternation of generations in seed-bearing plants 6';«, the male gametophyte, or pollen tube ; m, the male gamete, a nucleus at end of pollen tube ; Gf, the female gametophyte, or embryo sac ; /, the female gamete, a nucleus in the embryo sac; e, the fertilized egg, in embryo sac ; 5]^, young sporophyte, the embryo in the seed ; 6V,, the mature sporophyte, a flower-bearing plant; jj, the large spore, giving rise to the female gametophyte. or the embryo sac. So., the small spores, or pollen grains, giving rise to the male Stock Photo](https://c8.alamy.com/comp/MA76PW/elementary-biology-an-introduction-to-the-science-of-life-fig-153-alternation-of-generations-in-seed-bearing-plants-6-the-male-gametophyte-or-pollen-tube-m-the-male-gamete-a-nucleus-at-end-of-pollen-tube-gf-the-female-gametophyte-or-embryo-sac-the-female-gamete-a-nucleus-in-the-embryo-sac-e-the-fertilized-egg-in-embryo-sac-5-young-sporophyte-the-embryo-in-the-seed-6v-the-mature-sporophyte-a-flower-bearing-plant-jj-the-large-spore-giving-rise-to-the-female-gametophyte-or-the-embryo-sac-so-the-small-spores-or-pollen-grains-giving-rise-to-the-male-MA76PW.jpg ". Elementary biology; an introduction to the science of life . Fig. 153. Alternation of generations in seed-bearing plants 6';«, the male gametophyte, or pollen tube ; m, the male gamete, a nucleus at end of pollen tube ; Gf, the female gametophyte, or embryo sac ; /, the female gamete, a nucleus in the embryo sac; e, the fertilized egg, in embryo sac ; 5]^, young sporophyte, the embryo in the seed ; 6V,, the mature sporophyte, a flower-bearing plant; jj, the large spore, giving rise to the female gametophyte. or the embryo sac. So., the small spores, or pollen grains, giving rise to the male Stock Photo")
RMMA76PW–. Elementary biology; an introduction to the science of life . Fig. 153. Alternation of generations in seed-bearing plants 6';«, the male gametophyte, or pollen tube ; m, the male gamete, a nucleus at end of pollen tube ; Gf, the female gametophyte, or embryo sac ; /, the female gamete, a nucleus in the embryo sac; e, the fertilized egg, in embryo sac ; 5]^, young sporophyte, the embryo in the seed ; 6V,, the mature sporophyte, a flower-bearing plant; jj, the large spore, giving rise to the female gametophyte. or the embryo sac. So., the small spores, or pollen grains, giving rise to the male
RM2C3WCDN–The Biting Stonecrop is a ground hugging evergreen perennial with vivid star shaped yellow flowers. This hardy plant is common on rocky exposures
RF2C9CXKD–An extreme close-up or macro shot with shallow depth of field and very selective focus of a red rose flower petals in full bloom.
RM2AJC163–The natural history of plants, their forms, growth, reproduction, and distribution; . he whole organism, nothing could be urged against it. For what is instinctbut an unconscious and purposeful action on the part of a living organism ? Plants,then, possess instinct. We have instances of its operation in every swarm-spore VITAL FORCE, INSTINCT, AND SENSATION. 53 in search of the best place to settle in, and in every pollen-tube as it growsdown through the entrance to an ovary and applies itself to one definite spot ofan ovule, never failing in its object. The water-crowfoot, in deep water, fash
RMT03J4D–Elementary botany . elementarybotany00atki Year: 1898 Fig. 269. Fig. 270. Section of ovule of white pine, int, integ- Upper portion of nucellus of white pine, ument; A- pollen chamber; />/, pollen tube; A', pollen-grain remains; spc, sperm cells; «, nucellus; m, macrospore cavity. vn, vegetative nucleus; //, pollen tube. reached its full size, and where the archegonia begin to form before it Leaves the macrosporangium. 421. Male prcthallia. T>y the time the pollen is mature the male pro- thallum is already partly formed. In fig. 255 we can see two well-formed cells. Other cells are said
RMPG2JW2–. Morphology of gymnosperms. Gymnosperms; Plant morphology. CONIFERALES (PINACEAE) 275. and the pollen, caught in this pollination drop, is conveyed to the nucellus (fig. 315). The pollen tube begins to grow into the nucellus as soon as the spore is deposited, and continues to develop until it is checked by cold weather. The next spring the tube begins to renew its penetration of the nucellus during April, about a year after the pollen mother cell entered upon the reduction divisions, the large tube nucleus enters the tube, and at the same time the generative cell divides into the stalk cell (
RMMCKD8G–. being examined with the microscope, will be seen to con- sist of definite bodies, varying in size and shape in dif- ferent plants (fig. 7, a), being globose, oblong, like grains of wheat, or tri-lobed. Their surface is either dotted, striated, smooth, rough, or prickly. On the application of moisture, they after a time burst and protrude a thread-like body called the pollen tube (fig. 7, d), which is the essence of fertilization. {See Fertilization.) The Pistil.—The pistil or pistils, there being often more than one in a flower, is seated on the ovary, and, when perfect, consists of two part
RM2C3WCCD–The Biting Stonecrop is a ground hugging, evergreen perennial with vivid star shaped yellow flowers. This hardy plant is common on rocky exposures
RF2C9CXKJ–An extreme close-up or macro shot with shallow depth of field and very selective focus of a red rose flower petals in full bloom.
RM2ANFCY0–Farm grasses of the United States; a practical treatise on the grass crop, seeding and management of meadows and pastures, descriptions of the best varieties, the seed and its impurities, grasses for special conditions, etc., etc . cle in the ovule, and thetwo then begin to grow and a seed is formed. Thelittle particle in the ovule cannot grow unless it uniteswith the similar particle from the pollen tube. It isfrequently the case that ears of corn on the west sideof a field have grains missing. This is due to the factthat while the pollen was falling the wind blew mostof it away, and some of
RMRWWE4Y–Elementary botany (1898) Elementary botany elementarybotany00atki Year: 1898 Fig- 459- Proterandry in the bell-flower (campanula). Left figure shows the svngencecious stamens surrounding the immature style and stigma. Middle figure shows the immature stigma being pushed through the tube and brushing out the pollen : while in the right-hand figure, after the pollen has disappeared, the lobes of the stigma open out to receive pollen from another flower. the insect, will not touch the stigma of the same flower, but will be in posi- tion to come in contact with the stigma of the next flower visit
RMPG3KYA–. Physiological botany; I. Outlines of the histology of phænogamous plants. II. Vegetable physiology. Plant physiology; Plant anatomy. DESCENT OF THE POLLEN-TUBE. 431 pistil with a large number of ovules the stigmatic surface is large, as is also the amount of conductive tissue of the stj-ie through which the pollen-tubes are to descend. 1118. The conductive tissue through which the pollen-tube descends, and by which it is nourished, is formed at the stigma by a modification of epidermal ceUs, and below this arises from modifications in the parenchyma; in the style it may constitute a solid ma
RMMA76RY–. Elementary biology; an introduction to the science of life . Fig. 134. Fertilization in a flower When a pollen grain,/, alights on the moist surface of a stigma, s, it absorbs water and puts forth a thread of proto- plasm, or a pollen tube,//, which grows down the style into the ovary. The tip of the pollen tube finds its way to the inside of the ovule, 0, through a small passageway, the micropyle, m. The large cell in the middle of the ovule, called the embryo sac, es, undergoes a number of changes which result in pro- ducing several nuclei. One of these nuclei at the end nearest the microp
RM2BPHTXG–The Primrose is one of the first springtime plants to flower and are a pretty sight giving colour to the woodlands and cliff tops
RF2C9CXKK–An extreme close-up or macro shot with shallow depth of field and very selective focus of a red rose flower petals in full bloom.
RM2AFYNEX–. The cell; outlines of general anatomy and physiology. f Liliummartagon (after GuignardXV., Fig. 75). At the end ofthe pollen.tube, whose weak-ened wall is allowing itscontents to eccape, thesperm-nucleus may be seenwith its two centrosomes.The egg-nucleus is also pro-vided with two centrosomes.On the right, at the end ofthe pollen tube, a synergidamay be distinguished whichhas commenced to disinte-grate. 264 THE CELL it presses between the two synergidae right into the egg-cell.The pollen grain and the pollen tube contain two nuclei, thevegetative one, which takes no part in fertilisation, a
RMT0D362–Elementary botany (1898) Elementary botany elementarybotany00atki Year: 1898 Fig- 459- Proterandry in the bell-flower (campanula). Left figure shows the svngencecious stamens surrounding the immature style and stigma. Middle figure shows the immature stigma being pushed through the tube and brushing out the pollen : while in the right-hand figure, after the pollen has disappeared, the lobes of the stigma open out to receive pollen from another flower. the insect, will not touch the stigma of the same flower, but will be in posi- tion to come in contact with the stigma of the next flower visit
RMPFYT5A–. Handbook of nature-study for teachers and parents, based on the Cornell nature-study leaflets. Nature study. S88 handbook of Nature-Stttdy keep away the insrcts which carry the teasel's pollen. The pollen of the teasel is white and globular, with three little rosettes arranged at equal distances upon it like a bomb with three fuses. These little rosettes are the growing points of the pollen grains and from any of them may emerge the pollen tube to push down into the stigma. The teasel pollen is an excellent subject for the children to study, since it is so very large; and if examined with a
RMMA71NP–. Elementary botany . ^AreH Fig. 272. Last division of the egg in the white pine cutting off the ventral canal cell at the apex of the archegonium. End, endosperm; Arch, archegonium. theridium. there being no wall formed. The sperm mother cell also passes down the tubular sac, and divides again into two sperm cells, as shown in fig. 270. About this time, or rather a little earlier, with the pollen tube part way through the nucellar cap, winter overtakes it, and all growth ceases until the following spring. 426. Fertilization.—In the spring the advance of the pollen tube con- tinues, and it fin
RM2A2CTXK–The Peacock is a spectacular visitor to garden flowers. They are able to hibernate through the harsh winter and are early to be active in spring
RF2C5M2T8–A macro shot or an extreme close-up of a red amaryllis flower in full bloom with a very shallow depth of selective focus.
RM2AJC2F3–Elementary botany . 306 MORPHOLOGY. gates by the formation of a tube, forming a sac, known as the pollen tube.It is either simple or branched. It grows down into the tissue of the nu-cellus, and at a stage represented in fig. 358, winter overtakes it and itrests. At this time the central cell has divided into two cells, and thevegetative nucleus is in the pollen tube. 622. The endosperm.—In the following spring growth of all these parts. Fig. 359-Section of nucellus and endosperm of white pine. The inner layer of cells ofthe integument shown just outside of nucellus; arch, archegonium; en, egg
RMT03PR3–Elementary botany . elementarybotany00atki Year: 1898 GAMETOPHYTE AX J) SPOROPHYTE. 229 of pear fruit, the latter being kept in a moist chamber to prevent drying the surface. 452. In the spring after flowering the pollen escapes from the anther sacs, and as a result of pollination is brought to rest on the stigma of the pistil. Here it germinates, as we saw that is it develops a long tube which makes its way down through the style, and in through the micropyle to the embryo sae. where, in accordance with what takes place in other plants examined, one of the sperm cells unites with the egg, an
RMPG2K9R–. Morphology of gymnosperms. Gymnosperms; Plant morphology. 15° MORPHOLOGY OF GYMNOSPERMS. ary between the two becomes indistinct (fig. 177). Nothing is known of the behavior of chromatin during fertiHzation. The prominent development of the pollen tube as an absorbing organ suggests a question as to its original significance. In the Cycadofilicales the pollen grains are in close proximity to the egg, and there is nothing to indicate that any pollen tube was formed. In the cycads and in Ginkgo the pollen tube in the earlier stages of its development functions only as a haustorium. The pollen g
RMMA71AT–. Elementary botany . Fig. 288. Spermatozoids of zamia in pollen tube j>g, pollen grain; «, a, spermatozoids. (After Webber.) Fig. 289. Spermatozoidof zamia showing spiral row of cilia. (After Webber.) Class 1. Class 2. Class 3. Class 4. Gnetales. Cycadales ; family Cycadaceae. Cycas, zamia, etc. Gingkoales ; family Gingkoaceae. Gingko. Coniferae ; family I. Taxaceae. Taxus, the common yew in the eastern United States, and Torreya, in the western United States, are examples, family 2. Pinaceae. Araucaria (redwood of California), firs, spruces, pines, cedars, cypress, etc. Welwitschia mirabi
RM2T56HN7–The distinctive scalloped shape of the outer edges of the wings make the Comma an easy butterfly to identify.
RF2C5M2W2–A macro shot or an extreme close-up of a red amaryllis flower in full bloom with a very shallow depth of selective focus.
RM2AJBEHG–Elementary botany . .,) a portion Of of fertilization in angiosperm. f, funicle of ovule; J7 / r n, nucellus; in, micropyle; o, antipodal cells or the nucellus remains in- embryo sac ; e, endosperm nucleus ; /-egg cell and synergids ; at, outer integument of ovule ; z/, innertact in the mature Seed, integument. The track of the pollen tube is shown down through the style, walls of the ovary to the In such seeds the remain- mkropyiar end of the embryo sac.ing portion of the nucellus is the perisperm. 662. Presence or absence of endosperm in the seed.—Inmany of the angiosperms all of the endospe
RMRWPRT4–The elements of botany for The elements of botany for beginners and for schools elementsbotany00gray Year: 1887 1G8 CRYPTOGAMOUS OR FLOWERLESS PLAxNTS. [SECTION 17. shaped pieces, with au iulerual stalk, and bearing long aud ribbuu-shaped fdameiits, which cunsist of a row of delicate cells, each of vvhicli dis- charges a free-moving microscopic thread (the analogue of the pollen or p.ollen-tube), nearly in the manner of Ferns and Mosses. One of these threads reaches aud fertilizes a cell at the apex of the nucleus or sohd body of the sporocarj). This subsequently germinates aud forms a new in
RMPFN698–. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. Ovule of the same at the period of impregnation. x, the external integument; c, the internal, which immediately surrounds e, the embryo-sac. The pollen tube p, after passing the wide exostome becomes sensibly narrowed as it penetrates the canal leading to the embryo-sac, with the out- side of which its termination is in contact. 180 diam. 108. The anther and the pollen cell.—The history of the development of the anther is remarkably uniform among the different families Fig. 198. The same, some time uf'.er impregnation. T
RMMA71KN–. Elementary botany . Fig. 269. Fig. 270. Section of ovule of white pine, int, integ- Upper portion of nucellus of white pine, ument; A- pollen chamber; />/, pollen tube; A', pollen-grain remains; spc, sperm cells; «, nucellus; m, macrospore cavity. vn, vegetative nucleus; //, pollen tube. reached its full size, and where the archegonia begin to form before it Leaves the macrosporangium. 421. Male prcthallia. T>y the time the pollen is mature the male pro- thallum is already partly formed. In fig. 255 we can see two well-formed cells. Other cells are said to be formed earlier, but they b
RM2FN5CYW–In early Spring the Primrose is one of the first wild flowers to come into bloom. They are the ancestors of the Primula, much favoured by gardeners
RF2C5M2WN–A macro shot or an extreme close-up of a red amaryllis flower in full bloom with a very shallow depth of selective focus.
RM2AN3D82–Introduction to structural and systematic botany, and vegetable physiology, : being a 5th and revedof the Botanical text-book, illustrated with over thirteen hundred woodcuts . becomesone when a pollen-tube reaches theembryo-sac, the first known result offertilization being that a coat of cel-lulose is deposited upon its surface.This newly-formed cell grows bycell-multiplication (33), either pro-ducing a mass of cells, as shown inFig. 10 - 14, or else in the first placedeveloping into an elongated cell ora thread-shaped chain of cells (thesuspensor), the lower cell of whichdivides in all direc
RMT0D363–Elementary botany (1898) Elementary botany elementarybotany00atki Year: 1898 Fig- 459- Proterandry in the bell-flower (campanula). Left figure shows the svngencecious stamens surrounding the immature style and stigma. Middle figure shows the immature stigma being pushed through the tube and brushing out the pollen : while in the right-hand figure, after the pollen has disappeared, the lobes of the stigma open out to receive pollen from another flower. the insect, will not touch the stigma of the same flower, but will be in posi- tion to come in contact with the stigma of the next flower visit
RMPG2KA6–. Morphology of gymnosperms. Gymnosperms; Plant morphology. CYCADALES I4S cilia that pass through the outer border of the sperm and project for some distance. It has been claimed that the two cells formed by the division of the body cell become ciliated and are themselves the sperms. Ikeno. Figs. 170-172.—Sperms of cycads, represented as not formed within mother cells, but as consisting of the entire transformed halves of body cells: fig. 170, Zamia; pollen tube with sperms just before they begin to swim; X90; fig. 171, Cycas revoluia; the sperms at the beginning of movement; fig. 172, Cycas r
RMMA7729–. Elementary biology; an introduction to the science of life . Fig. 5. Various kinds of plant cells /, epidermal, or skin, cells of a leaf, showing the outer wall greatly thickened, and the cuticle; s, co- lumnar cells, like those of the palisade layer of a leaf pulp; 3, moving ciliated cells, like those of typhoid bacilli; 4, swimming spores of a water mold ; J, budding cells, like those of the yeast plant; 6, guard cells inclosing a breathing hole, or stomate^ on the surface of a leaf; 7, a pollen tube growing out of a pollen grain that seems to be denser than the rest. This is called the ke
RM2FN4R23–The Wood Anemone and Primrose are spring flowers that carpet the floor of deciduous woodland in suitable habitats. They flower before the canopy opens
RF2C5M2R4–A macro shot or an extreme close-up of a red amaryllis flower in full bloom with a very shallow depth of selective focus.
![Students' handbook to accompany Plants and their uses . t ulie ( the ])ollen tnlie ), which finally reaches the interior of theoMilc, where there is a very small e^. This egg is fertilizedliy its union with a small, v l.ody carried hy the pollen tube,and from the result of this fert ili/at ion a new emUryo cornplant develops within the ovule. While still within the de-veloping ovule, or seed, this young plant produces its roottip and stem tip: in corn and other grass seeds there is aspecial structure ( scutellum ) hy means of which the embryo THE PLANT AS A WOEKING MACHINE 17 plant absorbs foo Stock Photo](https://c8.alamy.com/comp/2AN8CWP/students-handbook-to-accompany-plants-and-their-uses-t-ulie-the-ollen-tnlie-which-finally-reaches-the-interior-of-theomilc-where-there-is-a-very-small-e-this-egg-is-fertilizedliy-its-union-with-a-small-v-lody-carried-hy-the-pollen-tubeand-from-the-result-of-this-fert-iliat-ion-a-new-emuryo-cornplant-develops-within-the-ovule-while-still-within-the-de-veloping-ovule-or-seed-this-young-plant-produces-its-roottip-and-stem-tip-in-corn-and-other-grass-seeds-there-is-aspecial-structure-scutellum-hy-means-of-which-the-embryo-the-plant-as-a-woeking-machine-17-plant-absorbs-foo-2AN8CWP.jpg "Students' handbook to accompany Plants and their uses . t ulie ( the ])ollen tnlie ), which finally reaches the interior of theoMilc, where there is a very small e^. This egg is fertilizedliy its union with a small, v l.ody carried hy the pollen tube,and from the result of this fert ili/at ion a new emUryo cornplant develops within the ovule. While still within the de-veloping ovule, or seed, this young plant produces its roottip and stem tip: in corn and other grass seeds there is aspecial structure ( scutellum ) hy means of which the embryo THE PLANT AS A WOEKING MACHINE 17 plant absorbs foo Stock Photo")
RM2AN8CWP–Students' handbook to accompany Plants and their uses . t ulie ( the ])ollen tnlie ), which finally reaches the interior of theoMilc, where there is a very small e^. This egg is fertilizedliy its union with a small, v l.ody carried hy the pollen tube,and from the result of this fert ili/at ion a new emUryo cornplant develops within the ovule. While still within the de-veloping ovule, or seed, this young plant produces its roottip and stem tip: in corn and other grass seeds there is aspecial structure ( scutellum ) hy means of which the embryo THE PLANT AS A WOEKING MACHINE 17 plant absorbs foo
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