Which of the following are not eukaryotes?
A. algae
B. molds
C. protozoa
D. archaea
The correct answer and explanation is:
The correct answer is D. archaea.
Archaea are not eukaryotes. They are a separate group of microorganisms that belong to the domain Archaea, distinct from both eukaryotes and bacteria. Archaea are prokaryotic organisms, which means they lack a defined nucleus and membrane-bound organelles, unlike eukaryotes. Eukaryotic cells are characterized by having a true nucleus that houses their genetic material, as well as various membrane-bound organelles such as mitochondria, the endoplasmic reticulum, and the Golgi apparatus.
In contrast, algae, molds, and protozoa are all eukaryotic organisms.
Algae are photosynthetic organisms that can be unicellular or multicellular. They have chlorophyll and other pigments that allow them to perform photosynthesis. Algae are considered eukaryotes because they have a nucleus and other organelles.
Molds are a type of fungi that are also eukaryotic. They are typically multicellular organisms that grow in filaments called hyphae. Molds are classified as fungi, and like other fungi, they have a complex cellular structure with a true nucleus and other organelles.
Protozoa are a diverse group of single-celled eukaryotes. They can be found in various environments, including freshwater, marine, and soil. Protozoa often exhibit complex behaviors, such as movement and predation. They are considered eukaryotic because their cells contain a nucleus and other organelles.
In summary, archaea are prokaryotic organisms that differ significantly from eukaryotes like algae, molds, and protozoa, which all possess a true nucleus and other characteristics of eukaryotic cells.