AP BIOLOGY

Detailed explanation-1: -Besides the nucleus, two other organelles-the mitochondrion and the chloroplast-play an especially important role in eukaryotic cells. These specialized structures are enclosed by double membranes, and they are believed to have originated back when all living things on Earth were single-celled organisms.

Detailed explanation-2: -A cell is surrounded by a membrane, which has receptors on the surface. A cell has several small structures inside it, including the nucleus, mitochondria, endoplasmic reticulum, and Golgi complex. These all have specific functions in the cell.

Detailed explanation-3: -All cells contain non-membrane-bound organelles, but only eukaryotic cells contain membrane-bound organelles. Both membrane-bound organelles and non-membrane-bound organelles carry out essential cell functions and are enclosed by the cell membrane.

Detailed explanation-4: -So the correct answer is “Nucleus and mitochondria".

Detailed explanation-5: -Some references are strict in their definition of an organelle: an organelle is one that is surrounded by lipid bilayers. Based on this definition, they are particularly nucleus, endoplasmic reticulum, Golgi apparatus, mitochondria, and plastids (e.g. chloroplasts).