Question 1: Archaea are a group of single-celled microorganisms that are distinct from bacteria and eukaryotes. They often live in extreme environments and possess unique biochemical features. Understanding Archaea helps us learn about the origins of life and evolutionary processes.

Answer: Archaea are single-celled microorganisms distinct from bacteria, often found in extreme environments, with unique biochemical features that provide insights into the origins of life.

Question 2: Explain one key difference between Archaea and bacteria in terms of their cell wall composition.

Answer: Archaea have cell walls made of pseudopeptidoglycan, which differs from the peptidoglycan found in bacterial cell walls.

Question 1: Define Archaea and list two environments where they are commonly found.

Answer: Archaea are single-celled microorganisms that often live in extreme environments such as hot springs and deep-sea vents.

Question 2: Describe how Archaea contribute to the nitrogen cycle in ecosystems.

Answer: Some Archaea perform ammonia oxidation, converting ammonia into nitrite, which is an essential step in the nitrogen cycle.

Question 1: If an Archaea population doubles every 4 hours, how many organisms will there be after 24 hours if you start with 100 Archaea? Show your calculation using the formula: Final Population = Initial Population × 2^(number of doubling periods).

Answer: Final Population = 100 × 2^(24/4) = 100 × 2^6 = 100 × 64 = 6400

Question 1: Design a simple experiment to test whether Archaea can survive in high-salinity environments. Include the variables you would control and the safety precautions necessary.

Answer: An experiment could involve exposing Archaea samples to different salinity levels in controlled conditions, controlling variables such as temperature, pH, and nutrient availability. Safety precautions include wearing gloves and eye protection to handle microbial cultures and sterilizing equipment to prevent contamination.

Question 1: A study found that in a deep-sea vent, the Archaea population was 10,000 organisms per milliliter of sediment. After 6 months, the population increased to 40,000. Describe what this data suggests about the growth rate of Archaea in this environment.

Answer: The population increased fourfold over six months, indicating a rapid growth rate likely due to favorable conditions in the deep-sea vent environment.

Question 1: Multiple Choice: Which of the following is a characteristic unique to Archaea?

Answer: C) Cell walls made of pseudopeptidoglycan

Question 2: Fill in the blank: Archaea are considered part of the domain __________ in biological classification.

Answer: Archaea

Question 1: Explain how Archaea are used in biotechnology or industry, providing at least one example.

Answer: Archaea are used in biotechnology for processes like bioremediation of waste in extreme environments and in the production of enzymes that work at high temperatures, such as in PCR techniques.