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Spermatozoid egg cell Stock Photos and Images
RM2AWWFJT–The structure & development of the mosses and ferns (Archegoniatae) . tsupper third is colourless and nearly hyaline. This is the receptive spot, and it is here that the spermatozoid enters.The nucleus is of moderate size, and not rich in chromatin ; asmall but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until itcomes in contact with the membrane of the egg nucleus. Itafterwards contracts and assumes much the appearance of the 262 MOSSES AND FERNS CHAP. nucleus of the sperm cell previous to the differentiation of thespermatozoid.
![. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MARATTIALES 281 Upper third is colourless and nearly hyaline. This is the "receptive spot," and it is here that the spermatozoid enters. The nucleus is of moderate size, and not rich in chromatin; a small but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until it comes in contact with the membrane of the egg nucleus. It afterwards contracts and assumes much the appearance of the nucleus of the sperm cell previous to the d Stock Photo](https://c8.alamy.com/comp/PG059Y/the-structure-and-development-of-mosses-and-ferns-archegoniatae-plant-morphology-mosses-ferns-marattiales-281-upper-third-is-colourless-and-nearly-hyaline-this-is-the-quotreceptive-spotquot-and-it-is-here-that-the-spermatozoid-enters-the-nucleus-is-of-moderate-size-and-not-rich-in-chromatin-a-small-but-distinct-nucleolus-is-present-the-spermatozoid-retains-its-original-form-after-it-first-enters-the-egg-and-until-it-comes-in-contact-with-the-membrane-of-the-egg-nucleus-it-afterwards-contracts-and-assumes-much-the-appearance-of-the-nucleus-of-the-sperm-cell-previous-to-the-d-PG059Y.jpg ". The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MARATTIALES 281 Upper third is colourless and nearly hyaline. This is the "receptive spot," and it is here that the spermatozoid enters. The nucleus is of moderate size, and not rich in chromatin; a small but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until it comes in contact with the membrane of the egg nucleus. It afterwards contracts and assumes much the appearance of the nucleus of the sperm cell previous to the d Stock Photo")
RMPG059Y–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MARATTIALES 281 Upper third is colourless and nearly hyaline. This is the "receptive spot," and it is here that the spermatozoid enters. The nucleus is of moderate size, and not rich in chromatin; a small but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until it comes in contact with the membrane of the egg nucleus. It afterwards contracts and assumes much the appearance of the nucleus of the sperm cell previous to the d
RMMA73JG–. Elementary botany . Fig. Fig. 117 Two sporocarps still surrounded by thallus. Thallus finally decays and sets sporocarp tree. Figs. 117, 11s, ('. scutata. times four in number or less (fig. iS. Sporocarp ruptured b y growth of egg to form cell theridia grow out from the mass. Cells of this sporo- . • 1 11 • 1 phyte forming zoospores. end 01 terminal cells in the form of short flasks, some- 16). A -ingle spermatozoid is formed from the contents. It is oval and potaesses two long cilia. Alter swim-
RM2AJBAGY–Elementary botany . romosomes. 344 MORPHOLOG Y. When fertilization takes place the number of chromosomesis doubled in the embryo.—In the spermatozoid of osmundathen, as well as in the egg, since these are developed on the game-tophyte, there are twelve chromosomes each. The same is truein the sperm-cell (generative cell) of lilium, and also in the egg-cell. When these nuclei unite, as they do in fertilization, thepaternal nucleus with the maternal nucleus, the number of chro-mosomes in the fertilized egg, if we take lilium as an example,is twenty-four instead of twelve; the number is doubled.
RMPG1Y6A–. Lectures on the evolution of plants. Botany; Plants. 54 EVOLUTION OP PLANTS 9, C, an), and closely resemble the zoospores except in size, and the partial or complete loss of chlorophyll. The spermatozoid has a large nucleus with relatively little cytoplasm, as the nucleus is probably of the most impor- tance in the act of fecundation. At maturity the oogonium opens and permits the en- trance of the motile spermatozoid, which at once pene- trates into the egg-cell where its nucleus fuses with that of the egg, thus fertilizing it. As the result of fertilization the egg becomes in- vested with
RMMA73NA–. Elementary botany . Fig. 116. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (ant); egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is • formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a 183? plant as C. scutata they are formed in a ring near the margin of the dis
RM2AWR4WD–The structure & development of the mosses and ferns (Archegoniatae) . Fig. 211.—Pilularia glolmlifcra (L.). A, B,Young female prothallia, longitudinal sec-tions, X 300 ; c, neck canal cell; C, sectionof a recently fertilised archegonium, X 300 ;sp, spermatozoid within the egg. large, but in Marsilia it is thelarger. In both, the receptivespot is evident. The nucleusis unusually small in Marsilia,which otherwise resemblesPilularia. The phenomena of fecunda-tion are very striking in theMarsiliacese. The mucilagin-ous layer about the macrospore attracts and retains thespermatozoids, which collect
RMPG1Y1C–. Lectures on the evolution of plants. Botany; Plants. THE FERNS 129 phyte may be described as amphibious, inasmuch as it must become aquatic, so to speak, in order that fertili- zation may be effected. The spermatozoid, attracted by the substance ejected from the open archegonium, swims to it and makes its way through the canal in the neck to the central cavity, where it quickly pene- trates the egg- cell and slowly fuses with its nucleus, after undergoing a se- ries of changes. As a result of fertilization the egg begins to grow, having in the mean time secreted a wall about itself, and thus
RM2AJDPN0–Elementary botany . Fig. 159. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (nut); egg inoogonium and surrounded by enveloping threads ; at center three antheridia open, and onespermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (fig. 159). Several oogonia are formed on one plant, and in such a IS55T plant as C. scutata they areformed in a ring near themargin of the disk. 328.
RM2AJDPCM–Elementary botany . Fig. 159. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (nut); egg inoogonium and surrounded by enveloping threads ; at center three antheridia open, and onespermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (fig. 159). Several oogonia are formed on one plant, and in such a IS55T plant as C. scutata they areformed in a ring near themargin of the disk. 328.
![. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MARATTIALES 281 Upper third is colourless and nearly hyaline. This is the "receptive spot," and it is here that the spermatozoid enters. The nucleus is of moderate size, and not rich in chromatin; a small but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until it comes in contact with the membrane of the egg nucleus. It afterwards contracts and assumes much the appearance of the nucleus of the sperm cell previous to the d Stock Photo](https://c8.alamy.com/comp/RDFCB6/the-structure-and-development-of-mosses-and-ferns-archegoniatae-plant-morphology-mosses-ferns-marattiales-281-upper-third-is-colourless-and-nearly-hyaline-this-is-the-quotreceptive-spotquot-and-it-is-here-that-the-spermatozoid-enters-the-nucleus-is-of-moderate-size-and-not-rich-in-chromatin-a-small-but-distinct-nucleolus-is-present-the-spermatozoid-retains-its-original-form-after-it-first-enters-the-egg-and-until-it-comes-in-contact-with-the-membrane-of-the-egg-nucleus-it-afterwards-contracts-and-assumes-much-the-appearance-of-the-nucleus-of-the-sperm-cell-previous-to-the-d-RDFCB6.jpg ". The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MARATTIALES 281 Upper third is colourless and nearly hyaline. This is the "receptive spot," and it is here that the spermatozoid enters. The nucleus is of moderate size, and not rich in chromatin; a small but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until it comes in contact with the membrane of the egg nucleus. It afterwards contracts and assumes much the appearance of the nucleus of the sperm cell previous to the d Stock Photo")
RMRDFCB6–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. MARATTIALES 281 Upper third is colourless and nearly hyaline. This is the "receptive spot," and it is here that the spermatozoid enters. The nucleus is of moderate size, and not rich in chromatin; a small but distinct nucleolus is present. The spermatozoid retains its original form after it first enters the egg, and until it comes in contact with the membrane of the egg nucleus. It afterwards contracts and assumes much the appearance of the nucleus of the sperm cell previous to the d
RMRDX44K–. Lectures on the evolution of plants. Botany; Plants. 54 EVOLUTION OF PLANTS 9, C, an), and closely resemble the zoospores except in size, and the partial or complete loss of chlorophyll. The spermatozoid has a large nucleus with relatively little cytoplasm, as the nucleus is probably of the most impor- tance in the act of fecundation. At maturity the oogonium opens and permits the en- trance of the motile spermatozoid, which at once pene- trates into the egg-cell where its nucleus fuses with that of the egg, thus fertilizing it. As the result of fertilization the egg becomes in- vested with
RMRD462E–. Elementary botany. Botany. CAMETOPHYTE AND SFOJWPHYTE. 243 When fertilization takes place the number of chromosomes is doubled in the embryo.—In the spermatozoid of osmunda then, as well as in the egg, since these are developed on the game- tophyte, there are twelve chromosomes each. The same is true in the sperm-cell (generative cell) of lilium, and also in the egg- cell. When these nuclei unite, as they do in fertilization, the paternal nucleus with the maternal nucleus, the number of chro- mosomes in the fertilized egg, if we take lilium as an example, is twenty-four instead of twelve; th
RMRDWETE–. Elementary botany. Botany. GAMETOPHYTE AND SPOPOPHYTE. 243 When fertilization takes place the number of chromosomes is doubled in the embryo.—In the spermatozoid of osmunda then, as well as in the egg, since these are developed on the game- tophyte, there are twelve chromosomes each. The same is true in the sperm-cell (generative cell) of lilium, and also in the egg- cell. When these nuclei unite, as they do in fertilization, the paternal nucleus with the maternal nucleus, the number of chro- mosomes in the fertilized egg, if we take lilium as an example, is twenty-four instead of twelve; th
RMRDGW95–. Lectures on the evolution of plants. Botany; Plants. 54 EVOLUTION OP PLANTS 9, C, an), and closely resemble the zoospores except in size, and the partial or complete loss of chlorophyll. The spermatozoid has a large nucleus with relatively little cytoplasm, as the nucleus is probably of the most impor- tance in the act of fecundation. At maturity the oogonium opens and permits the en- trance of the motile spermatozoid, which at once pene- trates into the egg-cell where its nucleus fuses with that of the egg, thus fertilizing it. As the result of fertilization the egg becomes in- vested with
RMRE1P0G–. Elementary botany. Botany. GAMErOPHYTE AXD SPOROPBYTE. 243 â When fertilization takes place the number of chromosomes is doubled in the embryo.âIn the spermatozoid of osmunda then, as well as in the egg, since these are developed on the game- tophyte, there are twelve chromosomes each. The same is true in the sperm-cell (generative cell) oi lilium, and also in the egg- cell. When these nuclei unite, as they do in fertilization, the paternal nucleus with the maternal nucleus, the number of chro- mosomes in the fertilized egg, if we take lilium as an example, is twenty-four instead of twelve;
RMRDG4DK–. Lectures on the evolution of plants. Botany; Plants. THE FERNS 129 phyte may be described as amphibious, inasmuch as it must become aquatic, so to speak, in order that fertili- zation may be effected. The spermatozoid, attracted by the substance ejected from the open archegonium, swims to it and makes its way through the canal in the neck to the central cavity, where it quickly pene- trates the egg- cell and slowly fuses with its nucleus, after undergoing a se- ries of changes. As a result of fertilization the egg begins to grow, having in the mean time secreted a wall about itself, and thus
RMRDX3XH–. Lectures on the evolution of plants. Botany; Plants. THE FERNS 129 phyte may be described as amphibious, inasmuch as it must become aquatic, so to speak, in order that fertili- zation may be effected. The spermatozoid, attracted by the substance ejected from the open archegonium, swims to it and makes, its way through the â canal in the neck to the central cavity, where it quickly pene- trates the egg- cell and slowly fuses with its nucleus, after undergoing a se- ries of changes. As a result of fertilization the egg begins to grow, having in the mean time secreted a wall about itself, and t
RMRE0PDC–. Elementary botany. Botany. CEDOGONIUM. lOI opening through which the spermatozoid entered to fecundate the egg. 238. Dwarf male plants.—In some species there will also be seen peculiar club-shaped dwarf plants attached to the side of the oogonium, or near it, and in many cases the end of this dwarf plant has an open lid on the end. 239. Antheridium.—The end cell of the dwarf male in such species is the antheridium. In other species the spermatozoids are developed in different cells (antheridia) of the same thread which bears the oogonium, or on a different thread. 240. Zoospore stage of oedo
RMRD2HN2–. Elementary botany. Botany. CEDOGONIUM. IOI opening through which the spermatozoid entered to fecundate the egg. 238. Dwarf male plants.—In some species there will also be seen peculiar club-shaped dwarf plants attached to the side of the oogonium, or near it, and in many cases the end of this dwaif plant has an open lid on the end. 239. Antheridium.—The end cell of the dwarf male in such species is the antheridium. In other species the spermatozoids are developed in different cells (antheridia) of the same thread which bears the oogonium, or on a different thread. 240. Zoospore stage of cedo
RMRE2NC1–. Elementary botany. Botany. (EDOGONIUM. 149 opening through which the spermatozoid entered to fecundate the egg. 313. Dwarf male plants.—In some species there will also be seen peculiar club-shaped dwarf plants attached to the side of the oogonium, or near it, and in many cases the end of this dwarf plant has an open lid on the end. 314. Antheridium.—The end cell of the dwarf male in such species is the antheridmm. In other species the spermatozoids are developed in different cells (antheridia) of the same thread which bears the oogonium, or on a different thread. 316. Zoospore stage of cedog
RMRDWGEN–. Elementary botany. Botany. CEDOGONIUM. IOI opening through which the spermatozoid entered to fecundate the egg. 238. Dwarf male plants.—In some species there will also be seen peculiar club-shaped dwarf plants attached to the side of the oogonium, or near it, and in many cases the end of this dwarf plant has an open lid on the end. 239. Antheridium.—The end cell of the dwarf male in such species is the antheridium. In other species the spermatozoids are developed in different cells (antheridia) of the same thread which bears the oogonium, or on a different thread. 240. Zoospore stage of cedo
RMRDWGCN–. Elementary botany. Botany. Fig. 116. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (ant)i egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of the dis
RMRD2HKA–. Elementary botany. Botany. Fig. 116. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (ant); egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is • formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a 183? plant as C. scutata they are formed in a ring near the margin of
RMRE0C2K–. Senescence and rejuvenescence. Age; Reproduction. THE GAMETES IN PLANTS AND ANIMALS 317 P.. Figs. 123-127.—Gametes of various algae: Fig. 123, young egg cell of Vohox aureus, connected with surrounding vegetative cells by numerous plasmatic strands (from Klein, '89); Fig. 124, spermatozoid of Vohox aureus (from Klein, '89); Fig. 125, part of filament of Oedogonium, showing oogonium with large egg and below three antheridia, from two of which spermatozoids have escaped (from Coulter, etc., '10); Fig. 126, branch of Chara, bearing oogonium, og, containing a single egg and antherid- ium, an (af
![. Elementary botany. Botany. Fig. 150. Coleoch^te soluta : at left branch bearing oogonium ^ooi:) antheridia imit): egg in oogonium and surrounded by enveloping threads : at center three antheridia open, and" one spermatozoid : at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube wliich opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (tig. 159). Several oogonia are farmed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of Stock Photo](https://c8.alamy.com/comp/RE2NB1/elementary-botany-botany-fig-150-coleochte-soluta-at-left-branch-bearing-oogonium-ooi-antheridia-imit-egg-in-oogonium-and-surrounded-by-enveloping-threads-at-center-three-antheridia-open-andquot-one-spermatozoid-at-right-sporocarp-mature-egg-inside-sporocarp-wall-cell-elongates-into-a-slender-tube-wliich-opens-at-the-end-to-form-a-channel-through-which-the-spermatozoid-may-pass-down-to-the-egg-the-egg-is-formed-of-the-contents-of-the-cell-tig-159-several-oogonia-are-farmed-on-one-plant-and-in-such-a-plant-as-c-scutata-they-are-formed-in-a-ring-near-the-margin-of-RE2NB1.jpg ". Elementary botany. Botany. Fig. 150. Coleoch^te soluta : at left branch bearing oogonium ^ooi:) antheridia imit): egg in oogonium and surrounded by enveloping threads : at center three antheridia open, and" one spermatozoid : at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube wliich opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (tig. 159). Several oogonia are farmed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of Stock Photo")
RMRE2NB1–. Elementary botany. Botany. Fig. 150. Coleoch^te soluta : at left branch bearing oogonium ^ooi:) antheridia imit): egg in oogonium and surrounded by enveloping threads : at center three antheridia open, and" one spermatozoid : at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube wliich opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (tig. 159). Several oogonia are farmed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of
RMRE0PAR–. Elementary botany. Botany. Fig. 116. Coleoch^ete soluta; at left branch bearing oogonium (oog) antheridia (nnt); egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a plant as C. scutata they are formed in cl ring near the margin of the dis
![. Elementary botany. Botany. Fig. 150. Coleoch^te soluta : at left branch bearing oogonium ^ooi:) antheridia imit): egg in oogonium and surrounded by enveloping threads : at center three antheridia open, and" one spermatozoid : at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube wliich opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (tig. 159). Several oogonia are farmed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of Stock Photo](https://c8.alamy.com/comp/RE2NAY/elementary-botany-botany-fig-150-coleochte-soluta-at-left-branch-bearing-oogonium-ooi-antheridia-imit-egg-in-oogonium-and-surrounded-by-enveloping-threads-at-center-three-antheridia-open-andquot-one-spermatozoid-at-right-sporocarp-mature-egg-inside-sporocarp-wall-cell-elongates-into-a-slender-tube-wliich-opens-at-the-end-to-form-a-channel-through-which-the-spermatozoid-may-pass-down-to-the-egg-the-egg-is-formed-of-the-contents-of-the-cell-tig-159-several-oogonia-are-farmed-on-one-plant-and-in-such-a-plant-as-c-scutata-they-are-formed-in-a-ring-near-the-margin-of-RE2NAY.jpg ". Elementary botany. Botany. Fig. 150. Coleoch^te soluta : at left branch bearing oogonium ^ooi:) antheridia imit): egg in oogonium and surrounded by enveloping threads : at center three antheridia open, and" one spermatozoid : at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube wliich opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (tig. 159). Several oogonia are farmed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of Stock Photo")
RMRE2NAY–. Elementary botany. Botany. Fig. 150. Coleoch^te soluta : at left branch bearing oogonium ^ooi:) antheridia imit): egg in oogonium and surrounded by enveloping threads : at center three antheridia open, and" one spermatozoid : at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube wliich opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (tig. 159). Several oogonia are farmed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of
RMRE0PAY–. Elementary botany. Botany. Fig. 116. Coleoch^ete soluta; at left branch bearing oogonium (oog) antheridia (nnt); egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a plant as C. scutata they are formed in cl ring near the margin of the dis
RMRD2HKD–. Elementary botany. Botany. Fig. 116. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (ant); egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is • formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a 183? plant as C. scutata they are formed in a ring near the margin of
RMRDWGCH–. Elementary botany. Botany. Fig. 116. Coleochaete soluta ; at left branch bearing oogonium (oog); antheridia (ant)i egg in oogonium and surrounded by enveloping threads ; at center three antheridia open, and one spermatozoid ; at right sporocarp, mature egg inside sporocarp wall. cell elongates into a slender tube which opens at the end to form a channel through which the spermatozoid may pass down to the egg. The egg is formed of the contents of the cell (fig. 116). Several oogonia are formed on one plant, and in such a plant as C. scutata they are formed in a ring near the margin of the dis
Search Results for Spermatozoid egg cell Stock Photos and Images (45)
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