Bernstein, Aaron, Naturwissenschaftliche Volksbücher, Bd. 17-21, 1897

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        <div xml:id="echoid-div8" type="section" level="1" n="8">
          <p>
            <s xml:id="echoid-s224" xml:space="preserve">
              <pb o="15" file="023" n="23"/>
            (wenn die Individuen paarweiſe zuſammenhängen),
              <emph style="sp">Strepto-
                <lb/>
              kokken</emph>
            , Fig. </s>
            <s xml:id="echoid-s225" xml:space="preserve">5 (wenn ſie zu längeren, perlſchnurähnlichen
              <lb/>
            Reihen vereinigt bleiben),
              <emph style="sp">Staphylokokken</emph>
            (wenn ſie größere
              <lb/>
            Häufchen, “Kolonien”, bilden). </s>
            <s xml:id="echoid-s226" xml:space="preserve">Geſchieht die Teilung gleich-
              <lb/>
            zeitig nach allen drei Richtungen des Raumes, ſo entſtehen
              <lb/>
            Warenballen-ähnliche Zellverbände. </s>
            <s xml:id="echoid-s227" xml:space="preserve">Bleiben die Individuen
              <lb/>
            bei gleichzeitiger Verquellung der Membranen zu zähen Maſſen
              <lb/>
            vereinigt, dann entſtehen die ſogenannten “Kahmhäute” oder
              <lb/>
            “
              <emph style="sp">Zooglöen</emph>
            “, welche, falls das Nährſubſtrat eine Flüſſigkeit
              <lb/>
            iſt, auf deren Oberfläche ſchwimmen.</s>
            <s xml:id="echoid-s228" xml:space="preserve"/>
          </p>
        </div>
        <div xml:id="echoid-div10" type="section" level="1" n="9">
          <head xml:id="echoid-head13" xml:space="preserve">
            <emph style="bf">IV. Fortpflanzung der Bakterien.</emph>
          </head>
          <p>
            <s xml:id="echoid-s229" xml:space="preserve">Die Fortpflanzung der Bakterien geſchieht auf zweierlei
              <lb/>
            Weiſe: </s>
            <s xml:id="echoid-s230" xml:space="preserve">1. </s>
            <s xml:id="echoid-s231" xml:space="preserve">durch Teilung und 2. </s>
            <s xml:id="echoid-s232" xml:space="preserve">durch Sporenbildung. </s>
            <s xml:id="echoid-s233" xml:space="preserve">Sobald
              <lb/>
            eine Bakterie eine beſtimmte Größe und Ausbildung erreicht
              <lb/>
            hat, zerfällt ſie einfach in zwei gleiche Teile, die heranwachſen
              <lb/>
            und wiederum eine einfache Teilung eingehen und ſo fort,
              <lb/>
            und zwar zerfällt bei günſtigen Bedingungen im Durchſchnitt
              <lb/>
            ein Bakterien-Individuum ſchon in zwei Teile, wenn es erſt
              <lb/>
            eine halbe Stunde alt iſt, deren jedes dann nach einer wei-
              <lb/>
            teren halben Stunde wieder zur Teilung in zwei Individuen
              <lb/>
            befähigt iſt.</s>
            <s xml:id="echoid-s234" xml:space="preserve"/>
          </p>
          <p>
            <s xml:id="echoid-s235" xml:space="preserve">Die zweite Art der Fortpflanzung iſt auch ſehr einfach,
              <lb/>
            aber doch immerhin komplizierter als die erſte. </s>
            <s xml:id="echoid-s236" xml:space="preserve">Unter be-
              <lb/>
            ſtimmten Umſtänden entſtehen dann z. </s>
            <s xml:id="echoid-s237" xml:space="preserve">B. </s>
            <s xml:id="echoid-s238" xml:space="preserve">im Innern der
              <lb/>
            Bakterien kleine, kugelige Zellen mit beſonders feſter Zellhaut,
              <lb/>
            die hierdurch und durch ihre ſonſtige Organiſation — wie wir
              <lb/>
            noch ſehen werden — beſonders widerſtandsfähig ſind. </s>
            <s xml:id="echoid-s239" xml:space="preserve">Es ſind
              <lb/>
            das die Fig. </s>
            <s xml:id="echoid-s240" xml:space="preserve">8 abgebildeten
              <emph style="sp">Sporen</emph>
            .</s>
            <s xml:id="echoid-s241" xml:space="preserve"/>
          </p>
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