What are spores primarily known for?

Spores are primarily known for their role in enabling certain organisms, particularly fungi, algae, and some bacteria, to survive in extreme conditions. They are highly resistant to environmental stressors such as desiccation, heat, and radiation. The structure of a spore allows it to endure harsh environments where conditions are unsuitable for growth and reproduction. For example, when conditions improve, spores can germinate and develop into new organisms. This survival mechanism is crucial for the continuation of species that face fluctuating or challenging environments.

Other options relate to functions that are not associated with spores. Neurons, for instance, are specialized cells responsible for transmitting nerve impulses, while nutrient reabsorption in kidneys pertains to a completely different biological process involving organ systems.