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What are the two layers of a Gram-Negative cell wall?

An inner peptidoglycan layer and an outer membrane containing proteins, phospholipids, and lipopolysaccharide (LPS).

What characterizes a Gram-Positive cell wall?

It has a very thick protective peptidoglycan layer and takes up the gram stain very well.

What is unique about Acid-Fast cell walls?

They contain a waxy layer of glycolipids and fatty acids (mycolic acid) and stain poorly with the gram stain but better with the acid-fast stain.

What are the three basic shapes of bacteria?

Cocci (spherical), Bacilli (rod-shaped), and Spirochetes (spiral).

What are the arrangements for cocci bacteria?

Pairs (Diplo), Chains (Strepto), Clusters (Staphylo), and Tetrads (Sarcinae).

What is the purpose of the Endospore Stain?

To stain bacterial spores, requiring a heated/steaming step to force the stain inside the cell.

What does the Gram Stain reveal about bacteria?

Gram-Positive bacteria stain blue/purple, while Gram-Negative bacteria stain red/pink.

What type of bacteria does the Acid Fast Stain target?

Bacteria with high lipid and wax content in their cell walls that do not stain well with traditional stains.

What are the steps to prepare a smear prep?

Place a drop of water on a slide, disinfect the loop, obtain a small sample, mix it into the water, disinfect the loop again, let it air dry, and heat fix.

What is the procedure for Gram staining?

1. Crystal Violet for 1 minute, rinse. 2. Iodine for 1 minute, rinse. 3. Decolorize with alcohol, rinse. 4. Safranin for 45 seconds, rinse, blot dry.

What are the two basic groups of bacteria based on nutritional requirements?

Autotrophs and Heterotrophs.

How do Autotrophs obtain their nutrients?

They grow using carbon dioxide as their sole carbon source, along with water and inorganic salts.

What do Heterotrophs require for energy?

An organic source of carbon, such as glucose, and they obtain energy by oxidizing or fermenting organic substances.

What are Obligate Anaerobes?

Organisms that cannot grow in the presence of oxygen.

What are Capnophilic organisms?

Organisms that require an atmosphere enriched with extra carbon dioxide.

What distinguishes Obligate Aerobes?

They require oxygen for growth.

What is the characteristic of Aerotolerant Anaerobes?

They survive in the presence of oxygen but do not use oxygen in metabolism.

What is the final electron acceptor in aerobic respiration?

Oxygen.

What is fermentation in bacteria?

An anaerobic process where the electron acceptor is an organic compound, resulting in less efficient energy generation.

What is the difference between anaerobic respiration and fermentation?

Anaerobic respiration can use nitrate or sulfate as the final electron acceptor, while fermentation uses organic compounds.