1.2 Feinstruktur von Zellen

Elektronenmikroskpope haben eine viel höhere Auflösung als Lichtmikroskope. Figure: E5-1 part c Title: Microscopes yesterday and today part c Electron microscope Caption: (c) A scanning electron microscope, which creates a three-dimensional image of a specimen’s surface.

Prokaryoten haben eine einfache Zellstruktur ohne Kompartimentierung

Bakterium Escherichia coli Figure: 19-7 part a Title: The prokaryote flagellum part a Caption: (a) A flagellated archaean of the genus Aquifex uses its flagella to move toward favorable environments.

Nukleoid (mit nackter DNA) Pili 70S Ribosomen Flagellum Zellwand Figure :5-2 Title: A generalized prokaryotic cell Caption: Zellwand Plasmamembran Plasmid (Ring aus DNA) Zytoplasma

Prokaryoten teilen sich durch binäre Fission.

Eukaryotische Zellen sind komplex und kompartimentiert.

Tierzelle Nukleus mit Chromosomen) Zytoplasma Raues Endoplasmatisches Reticulum Zytoplasma Plasma- membran Lysosom Figure :5-3 Title: A generalized animal cell Caption: Golgiapparat Vesikel Glattes Endoplasmatisches Reticulum Freie Ribosomen 80S Mitochondrium

Beispiel für eine Tierzelle: Drüsenzelle des Pankreas (Bauchspeicheldrüse)

Pflanzenzelle Mitochondrium Chloroplast Golgiapparat Vacuole glattes Endoplasmatisches Reticulum Vesikel raues Endoplasmiatisches Reticulum Zellwand Plasma- membran Figure :5-4 Title: A generalized plant cell Caption: Question Of the nucleus, ribosome, chloroplast, and mitochondrion, which appeared earliest in the history of life? Gebundene Ribosomen Freie Ribosomen 80S

Beispiel für eine Pflanzenzelle: Palisadenzelle des Laubblattes gewebe

Organellen: Funktionen Zellwand schützende Hülle Plasmamembran kontrolliert Ein- und Ausgang Plasmid Ring aus DNA Mesosom Zellatmung Vesikel beinhaltet Enzyme Zellkern steuert die Zelle, beinhaltet das Erbgut Zytoplasma beinhaltet Enzyme und Organellen Nukleoid nackte DNA Ribosomen Proteinsynthese Mitochondrien Chloroplasten Fotosynthese Pili Anheften an andere Zellen Flagellum Fortbewegung Golgiapparat Verarbeitung von Proteinen

Interpretation von Elektromikrogrammen

Nucleus Ribosomen Mitochondrien Rauhes Endo- Lysosomen plasmatisches Struktur Merkmale Zellkern/Nucleus rund, oval, nierenförmig, begrenzt von der Kernmembran Mitochondrien runde Form, sind im gesamten Zytoplasma verteilt Lysosomen gleichmäßige Form Golgi-Apparat unregelmäßige Struktur in der Nähe der Kernmembran, deutliche Intensität (rauhes) Endoplasmatisches Reticulum (ER) kammerförmige Struktur, liegt häufig um den Zellkern herum Ribosomen Kleine Punkte im Zytoplasma und auf dem ER Nucleus Ribosomen Mitochondrien Rauhes Endo- plasmatisches Reticulum Lysosomen Vesikel Golgi-Apparat

Zellkern Kern poren Figure :5-5 part b Title: The nucleus part b Caption: (b) An electron micrograph of a yeast cell that has been frozen and broken open to reveal its internal structures. The large nucleus, with nuclear pores penetrating its nuclear membrane, is clearly visible. Kern poren

raues endoplasmatisches Reticulum Ribosomen Figure :5-8 top right Title: Endoplasmic reticulum top right Caption: There are two types of endoplasmic reticulum: rough ER and smooth ER. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells, the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane. raues endoplasmatisches Reticulum 0.5 micrometer

glattes endoplasmatisches Reticulum Vesikel Figure :5-8 bottom right Title: Endoplasmic reticulum bottom right Caption: There are two types of endoplasmic reticulum: rough ER and smooth ER. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells, the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane. glattes endoplasmatisches Reticulum 0.5 micrometer

Mitochondrium Figure :5-13 Title: A mitochondrion Caption: Mitochondria consist of a pair of membranes enclosing two fluid compartments: the intermembrane compartment between the outer and inner membranes, and the matrix within the inner membrane. The outer membrane is smooth, but the inner membrane forms deep folds called cristae. 0.2 micrometer

Chloroplast Figure :5-14 Title: A chloroplast Caption: Chloroplasts are surrounded by a double membrane, although the inner membrane is not usually visible in electron micrographs. The fluid stroma is enclosed by the inner membrane; within the stroma are stacks of thylakoid sacs called grana. Chlorophyll is embedded in the membranes of the thylakoids. 1 micrometer

Identifiziere die Organellen

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9 Figure :5-8 top right Title: Endoplasmic reticulum top right Caption: There are two types of endoplasmic reticulum: rough ER and smooth ER. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells, the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane.

10 Figure :5-8 bottom right Title: Endoplasmic reticulum bottom right Caption: There are two types of endoplasmic reticulum: rough ER and smooth ER. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells, the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane.

Lösungen

1 Zellkern

2 Chloroplast

3 Chloroplast

4 Lysosomen

5 Mitochondrium

6 Zellwand

7 Vakuole

8 Golgiapparat

9 Raues ER Figure :5-8 top right Title: Endoplasmic reticulum top right Caption: There are two types of endoplasmic reticulum: rough ER and smooth ER. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells, the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane.

10 Vesikel Figure :5-8 bottom right Title: Endoplasmic reticulum bottom right Caption: There are two types of endoplasmic reticulum: rough ER and smooth ER. Although in electron micrographs the ER looks like a series of tubes and sacs, it is actually a maze of folded sheets and interlocking channels. In many cells, the rough and smooth ER are thought to be continuous, as depicted in the drawing. Ribosomes (black) stud the cytoplasmic face of the rough ER membrane.