AP BIOLOGY

Detailed explanation-1: -Both prokaryotes and eukaryotes have a cell membrane.

Detailed explanation-2: -Prokaryotic cells are surrounded by a plasma membrane, but they have no internal membrane-bound organelles within their cytoplasm. The absence of a nucleus and other membrane-bound organelles differentiates prokaryotes from another class of organisms called eukaryotes.

Detailed explanation-3: -Cell walls are found in both prokaryotes and eukaryotes, although not all cells have cell walls. In Figure 1, the diagram of a plant cell, you see a structure external to the plasma membrane which is the cell wall. The cell wall is the reason why vegetables such as celery crunch when you bite into them.

Detailed explanation-4: -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-5: -In prokaryotes, the DNA (chromosome) is in contact with the cellular cytoplasm and is not in a housed membrane-bound nucleus. In eukaryotes, however, the DNA takes the form of compact chromosomes separated from the rest of the cell by a nuclear membrane (also called a nuclear envelope).