Section Assessment 19.1
1. Describe the characteristics of the two kingdoms of prokaryotes. Eubacteria is the larger of them both. Eubacteria are usually surrounded by cell that protects from injury and determines its shape. Eubacteria have peptidoglycan. Archaebacteria lack the peptidoglycan of eubacteria and also have different membrane lipids. Also, the DNA sequences of key archaebacterial genes are more like those of eukaryotes than those of eubacteria. 2. What factors can be used to identify prokaryotes? Prokaryotes are identified by characteristics such as shape, the chemical nature of their cell walls, the way they move, and the way they obtain energy. 3. One example of how bacteria maintain equilibrium in the environment. Some are producers that capture energy by photosynthesis. Others are decomposers that break down the nutrients in dead matter and the atmosphere. Still other bacteria have human uses. 4. Identify the parts of a prokaryote. The parts of a prokaryote are cell wall, cell membrane, and cytoplasm. Some have flagella used for movement. 5. What are some ways that prokaryotes obtain energy? Most prokaryotes are heterotrophs, which means that they get their energy by consuming organic molecules made by other organisms. Other prokaryotes are autotrophs and make their own food from inorganic molecules. 6. Why might an infection by Gram-negative bacteria be more difficult to treat than a Gram-positive bacterial infection? An infection from a Gram-Negative would be more difficult to treat because alcohol makes the color dissolve because it has much thinner walls inside an outer lipid layer .