Biodiversity and Biological Classification

These flashcards cover key concepts about biodiversity, classification systems, and the characteristics of life.

What is biodiversity?

The variety within and among living species.

What percentage of species are known to science?

Only 20% are known to science.

Who are systematists?

Scientists specializing in describing and categorizing organism groups.

What is paleontology?

The scientific study of life that existed in the distant past.

What are the three domains of life?

Bacteria, Archaea, Eukarya.

What is the significance of DNA comparisons in biological classification?

Used to determine evolutionary relationships.

What event marks the beginning of the Cambrian period?

The sudden appearance of many animal groups.

What are the main characteristics of fungi?

Multicellular, rely on other organisms for food, reproduce by spores.

What is the endosymbiotic theory?

Mitochondria and chloroplasts descended from bacteria inside primitive eukaryotes.

What defines prokaryotic cells?

Cells without a nucleus or organelles.

What is the role of microbes in Earth's atmosphere?

Microbes produce more than half of Earth’s atmospheric oxygen.

What are ectothermic animals?

Animals that rely on external environmental conditions for temperature regulation.

Which kingdom do amoebae belong to?

Kingdom Protista.

How do viruses reproduce?

By hijacking the transcription machinery of host cells.

What classification system reflects evolutionary relationships?

The six-category system acknowledging three major domains.

What is a major characteristic of multicellular organisms?

They consist of multiple cells that work together.

What is the importance of vascular tissue in plants?

Transports water and nutrients, allowing plants to grow tall.

Which animals are considered vertebrates?

Animals with backbones.

What type of environment do many Archaea thrive in?

Extreme environments with high salinity or temperature.