Microbiology Lecture 2: Introduction of Bacteria

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What is the approximate size range of bacteria according to the text?

0.1 to 10.0 nm

0.1 to 10.0 mm

0.1 to 10.0 μm (correct)

0.1 to 10.0 cm

Which bacterial shape is described as rod-shaped?

Spirilla

Vibrios (correct)

Cocci

Actinomycetes

What is the process of bacterial reproduction mentioned in the text?

Binary fragmentation

Binary division

Binary fission (correct)

Binary fusion

Which type of bacteria is described as flexible spiral forms?

Spirochetes (B) Signup and view all the answers

What is the unit of measurement in bacteriology mentioned in the text?

Micrometer (μm) (B) Signup and view all the answers

Which type of bacteria is described as branching filamentous bacteria?

Spirochetes (B) Signup and view all the answers

What is the defining characteristic of mycoplasmas?

They lack a cell wall (B) Signup and view all the answers

Which of the following is NOT a component of the bacterial cell envelope?

Ribosomes (D) Signup and view all the answers

What is the primary function of the bacterial cell wall?

Providing shape and structural integrity (B) Signup and view all the answers

Which of the following is not a characteristic used to classify bacteria?

Cytoplasmic components (D) Signup and view all the answers

What is the purpose of the Gram stain in bacterial identification?

To differentiate between Gram-positive and Gram-negative bacteria (D) Signup and view all the answers

Which of the following is a common characteristic of Gram-positive bacteria?

Presence of a thin peptidoglycan layer (C) Signup and view all the answers

What is the main characteristic of a bacterial spore?

Low metabolism and low water content (D) Signup and view all the answers

Which of the following is NOT a property of bacterial spores?

Presence of cytochromes (C) Signup and view all the answers

What is the purpose of the spore coat in the structure of a bacterial spore?

To provide resistance to UV and ionizing radiation (A) Signup and view all the answers

Which of the following is the correct sequence of the layers in the structure of a bacterial spore?

Inner cytoplasmic membrane, peptidoglycan layer, cortex, outer membrane, spore coat (B) Signup and view all the answers

Which genera of bacteria are known to form endospores?

Bacillus and Clostridium (D) Signup and view all the answers

What is the purpose of the cortex in the structure of a bacterial spore?

To provide resistance through its concentric layers of peptidoglycans (D) Signup and view all the answers

Which of the following is not a stage in the germination process of a spore?

Spore replication (D) Signup and view all the answers

Which of the following can disrupt the spore shell structure to activate the spore?

All of the above (D) Signup and view all the answers

What is the purpose of the Gram staining process in bacterial identification?

All of the above (D) Signup and view all the answers

What is the role of iodine in the Gram staining process?

It acts as a mordant, fixing the crystal violet to the cell wall (A) Signup and view all the answers

Which of the following is not a common specimen used for laboratory diagnosis of bacterial infections?

Cerebrospinal fluid (A) Signup and view all the answers

Which of the following is a rapid indirect identification method for bacteria?

Latex Agglutination (C) Signup and view all the answers