MCQ IN MEDICINE

Detailed explanation-1: -Microorganisms can be unicellular (single cell), multicellular (cell colony), or acellular (lacking cells). They include bacteria, archaea, fungi, protozoa, algae, and viruses. Bacteria are single celled microbes that lack a nucleus.

Detailed explanation-2: -Unicellular organisms are made up of only one cell that carries out all of the functions needed by the organism, while multicellular organisms use many different cells to function. Unicellular organisms include bacteria, protists, and yeast.

Detailed explanation-3: -Many bacteria have a multicellular phase of their lifecycle, which fall into three broad categories based on shape and mechanism of formation. A number of pressures may have selected for multicellularity, including physicochemical stress, nutrient scarcity, predation, and environmental variability.

Detailed explanation-4: -Final Answer: Humans are not unicellular organisms.

Detailed explanation-5: -Bacteria and archaea are all unicellular prokaryotes. Eukaryotes do have cell nuclei and their structures are more complex. Yeasts and algae are examples of unicellular eukaryotes. Unlike prokaryote cells, eukaryote cells have organelles, cell organs fulfilling important functions in the cell.