Group: Chlamydias Viruses INTRODUCTION FOR THE PROKARYOTES (Domains Bacteria and Archaea) The domain Bacteria contains more than 4500 species of bacteria that have been characterized and many more exist. Bacteria are the most widespread organisms in the world. All of these organisms are made up of single prokaryotic cells although some will aggregate into groups or form colonies. Their genetic material (a single chromosome made up of DNA) is concentrated in a nucleoid region but has no nuclear membrane that separates this region from the rest of the cytosol. They also lack membrane-bound organelles. Bacteria range in size between 1 10 in size. This domain is usually broken up into a dozen groups based on sequences um um – of ribosomal RNA, shape [cocci (spherical), bacilli (rod-shaped), helices (spiral), and filaments], nutritional mode (photoautotrophs, chemoautotrophs, photoheterotrophs, and chemoheterotrophs), and the cell wall’s ability to gram-stain. The domain Archaea contains prokaryotic that usually inhabit the more extreme environments on Earth such as swamps and marshes without oxygen, extremely saline (salty) waters and extremely hot sulfur springs. These organisms have been separated from the other prokaryotic cells because of signature sequences in their ribosomal RNA and their nucleic acids. Station 1 Prokaryotic Cells – Know the following drawing with the correct names. (Figure 6.6, p 98 from Campbell & Reece) Station 2 Bacterial Shapes – Be able to identify the Use the slide of (in a chain) to become familiar shape cocci. Streptococcus lactis with this shape. (P 28, Fig 3.8 similar appearance to Streptococcus lactis Neisseria gonorrhoeae) – Station 3 Bacterial Shapes – Be able to identify the Use the slide of (with endospores) to become shape bacillus. Clostridium tetani familiar with this shape. (P 28, Fig 3.4 similar appearance to Clostridium tetani Bacillus megaterium) – Station 4 Bacterial Shapes –
Group: Chlamydias Viruses INTRODUCTION FOR THE PROKARYOTES (Domains Bacteria and Archaea) The domain Bacteria contains more than 4500 species of bacteria that have been characterized and many more exist. Bacteria are the most widespread organisms in the world. All of these organisms are made up of single prokaryotic cells although some will aggregate into groups or form colonies. Their genetic material (a single chromosome made up of DNA) is concentrated in a nucleoid region but has no nuclear membrane that separates this region from the rest of the cytosol. They also lack membrane-bound organelles. Bacteria range in size between 1 um – 10 um in size. This domain is usually broken up into a dozen groups based on sequences of ribosomal RNA, shape [cocci (spherical), bacilli (rod-shaped), helices (spiral), and filaments], nutritional mode (photoautotrophs, chemoautotrophs, photoheterotrophs, and chemoheterotrophs), and the cell wall’s ability to gram-stain. The domain Archaea contains prokaryotic that usually inhabit the more extreme environments on Earth such as swamps and marshes without oxygen, extremely saline (salty) waters and extremely hot sulfur springs. These organisms have been separated from the other prokaryotic cells because of signature sequences in their ribosomal RNA and their nucleic acids. Station 1 – Prokaryotic Cells Know the following drawing with the correct names. (Figure 6.6, p 98 from Campbell & Reece) Station 2 – Bacterial Shapes Be able to identify the shape cocci. Use the slide of Streptococcus lactis (in a chain) to become familiar with this shape. Streptococcus lactis (P 28, Fig 3.8 – similar appearance to Neisseria gonorrhoeae) Station 3 – Bacterial Shapes Be able to identify the shape bacillus. Use the slide of Clostridium tetani (with endospores) to become familiar with this shape. Clostridium tetani (P 28, Fig 3.4 – similar appearance to Bacillus megaterium) Station 4 – Bacterial Shapes