Of the following genera, which can survive the harshest conditions?
a. Staphylococcus
b. Clostridium
c. Mycobacterium
d. Actinomyces

Verified step by step guidance

1. Step 1: Understand the question is asking which genus can survive the harshest environmental conditions, such as extreme heat, desiccation, or chemical exposure.
2. Step 2: Recall that some bacteria form endospores, which are highly resistant structures allowing survival under extreme conditions.
3. Step 3: Identify which genera from the list are known to form endospores. Clostridium is a genus well-known for producing endospores.
4. Step 4: Consider the other genera: Staphylococcus, Mycobacterium, and Actinomyces do not form endospores and generally have less resistance to extreme conditions compared to spore-formers.
5. Step 5: Conclude that the genus capable of surviving the harshest conditions is the one that forms endospores, which is Clostridium.

Key Concepts

Bacterial Endospores

Endospores are highly resistant, dormant structures formed by certain bacteria like Clostridium. They can survive extreme heat, desiccation, radiation, and chemicals, allowing the bacteria to endure harsh environmental conditions until favorable growth conditions return.

Cell Wall Structure and Resistance

The composition of bacterial cell walls affects their resistance to environmental stress. For example, Mycobacterium has a waxy, lipid-rich cell wall that provides resistance to chemicals and desiccation, but it is less resistant than endospores to extreme conditions.

Environmental Adaptations of Bacterial Genera

Different bacterial genera have evolved various adaptations to survive stress. Staphylococcus and Actinomyces can tolerate some harsh conditions but lack specialized structures like endospores, making them less resilient compared to genera like Clostridium.