LIFE SCIENCE

Detailed explanation-1: -Answer and Explanation: The correct answer is A. a nucleus.

Detailed explanation-2: -Endoplasmic reticulum, microtubules, and the Golgi apparatus are unique to eukaryotic cells, and will not be found in prokaryotes.

Detailed explanation-3: -All cells have a plasma membrane, ribosomes, cytoplasm, and DNA. Prokaryotic cells lack a nucleus and membrane-bound structures. Eukaryotic cells have a nucleus and membrane-bound structures called organelles.

Detailed explanation-4: -Mitochondria, for example, are organelles that provide eukaryotes with most of their energy by producing energy-rich molecules called ATP. Prokaryotes lack mitochondria and instead produce their ATP on their cell surface membrane.

Detailed explanation-5: -Prokaryotic cells do not have mitochondria. Most prokaryotes rely on their immediate environment to obtain energy. This process is facilitated by the electron transport chains in the plasma membrane. Mitochondria are only found in eukaryotic cells.