Definition: A mathematical function that gives the angle whose cosine is a given number. It is the inverse of the cosine function.

Example: To find the angle, you can use the arccosine of the cosine value.

Definition: Relating to a group of single-celled microorganisms that are distinct from bacteria and eukaryotes, often found in extreme environments.

Example: The archaeal species thrive in hot springs and deep-sea vents.

Definition: Relating to the earliest known rocks and geological time period before the appearance of life on Earth.

Example: The archaeans are important for understanding the history of our planet.

Definition: A type of single-celled microorganism that belongs to the domain Archaea, often found in extreme environments.

Example: Scientists discovered a new archaebacterium thriving in the hot springs.

Definition: Connected to the study of ancient cultures and their artifacts through excavation and analysis.

Example: The archaeological team discovered ancient pottery during their dig.

Definition: A person who studies ancient cultures and human history by digging up and examining old sites and objects.

Example: The archaeologist discovered ancient pottery while excavating the site.

Definition: The study of ancient human history and cultures through the analysis of physical remains like tools, pottery, and buildings.

Example: She decided to pursue a career in archaeology because she loves discovering ancient artifacts.

Definition: A type of single-celled organism that is different from bacteria and often lives in extreme environments.

Example: Archaea are known for their ability to survive in harsh conditions, such as hot springs and salt lakes.

Definition: A long-extinct bird from the Jurassic period that had features of both birds and reptiles, such as feathers, teeth, and a bony tail.

Example: The archaeopteryx is often considered a key species in the study of evolution between dinosaurs and modern birds.

Definition: Connected to the female reproductive structure in certain plants, where eggs are produced.

Example: The archegonial structure is essential for the reproduction of mosses.