1.2 Ultra Structure of Cells

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1.2 Ultra Structure of Cells

-Electron microscopes have lighter resolution than light microscopes

-Prokaryotes have a simples cell structure without any compartments. They were the first organisms to evolve on earth. The following are prokaryote characteristics:

cytoplasm, nucleoid, ribosomes, pili, flagella, naked DNA, cell wall and plasma membrane. The nucleoid contains the chromosomes and genetic information of the cell. The cell wall is thick and strong and protects the cell from bursting and maintains its shape. Prokaryotes synthesize proteins in the cytoplasm.

-All bacteria are prokaryotes.

-Prokaryotes divide by binary fission, asexual reproduction that results in identical daughter cells.

-Eukaryotes have a compartmentalized cell structure. The compartments are known as organelles. The synthesis of protein is compartmentalized through different organelles in a eukaryotic cell. List of organelles:

1. Nucleus

2. Rough Endoplasmic Reticulum

3. Golgi Apparatus

4. Lysosome

5. Mitochondrion

6. Ribosomes

7. Chloroplast

8. Vacuoles & Vesicles

9. Microtubules & Centrioles

10. Cilia & Flagella

-Animals, plants and fungi are all eukaryotes.Plant and animal cells always have cytoplasm, mitochondrion and ribosomes. Golgi apparatus and nuclear membrane are exclusively found in eukaryotic cells.

-Eukaryotes can be visualized with a light microscope.

-Ribosome are found in all cell types.