Learn Chapter 2-Biological Classification with Top Tutors

Changes in Classification Systems Over Time: Classification systems have undergone changes due to advancements in scientific knowledge, improvements in technology, and revisions based on new evidence. As our understanding of evolutionary relationships and genetic information improves, taxonomists may reclassify organisms to reflect more accurate relationships.

Economically Important Uses of Heterotrophic Bacteria: Two economically important uses of heterotrophic bacteria include:

1. Bioremediation: Some heterotrophic bacteria are used to clean up environmental pollution by breaking down organic contaminants.
2. Industrial Fermentation: Heterotrophic bacteria are used in industrial fermentation processes to produce various products such as antibiotics, enzymes, and organic acids.

Meanings of 'Algal Bloom' and 'Red Tides':

• Algal bloom refers to a rapid increase in the population of algae in aquatic environments, often resulting in dense concentrations of algae visible on the water's surface.
• Red tides are a type of algal bloom caused by the rapid growth of certain species of algae, often dinoflagellates, which can lead to the discoloration of water and the release of toxins harmful to marine life.

Differences Between Viroids and Viruses:

• Viroids are small, circular RNA molecules that infect plants, while viruses are infectious agents that can infect various organisms including plants, animals, and bacteria.
• Viroids lack a protein coat (capsid), while viruses possess a protein coat surrounding their nucleic acid core.
• Viroids do not encode proteins, while viruses typically encode proteins necessary for their replication and infection.