Make thee an ark of gopher wood; with rooms shalt thou make the ark, and shalt pitch it within and without with pitch” (Genesis 6:14)
A light shalt thou make to the ark, and to a cubit shalt thou finish it upward; and the door of the ark shalt thou set in the side thereof; with lower, second, and third stories shalt thou make it. (Genesis 6:16)
And of every living thing of all flesh, two of every sort shalt thou bring into the ark, to keep them alive with thee; they shall be male and female. (Genesis 6:19)
And the Eternal said unto Noah: ‘Come thou and all thy house into the ark…’ (Genesis 7:1)
Kabbalah teaches that Noah’s ark was a microcosm of the world. The ark appears to be a biological microcosm as well, exhibiting structural parallels with a living cell.
The original Hebrew word for ark is tevah, which literally means a container. Notably, the word “cell” comes from cella, which means a “small room.” A room, of course, is a type of container. The parallel, however, goes far beyond the linguistic similarity.
A cell is the smallest unit of life. Noah’s ark was also the smallest unit of life on earth, because all other life perished in the flood. Using this biological metaphor, the ark can be considered a model of a unicellular organism.
A cell is contained with a membrane that protects the cell’s interior from the environment. The ark also served as the container protecting its inhabitants from the environment. Despite its protective function, the cell membrane is semipermeable, shielding the inner contents of the cell from the environment while selectively letting certain things from the environment through. Similarly, while protecting the ark’s inhabitants from the harsh environment and the raging waters of the flood, the walls of the ark had a window on top that let light into the ark. The ark also had a door to selectively let animals inside the ark.
In biology, cells come in two types: prokaryotic (bacteria and archaea) and eukaryotic (plants, animals, fungi, slime molds, protozoa, and algae). The main distinction between these two types is the compartmentalization of eukaryotic cells, whereas prokaryotic cells have no internal divisions. Noah’s ark was compartmentalized—it had three compartments—one for people, one for animals, and one for waste. Moreover, each type of animal had its own sub-compartment within the larger compartment for animals. In this sense, Noah’s ark is a model of a eukaryotic cell. The main feature of a eukaryotic cell is its nucleus. Following our cell metaphor, the first two compartments of the ark housing people and animals may be considered a model of a nucleus. The third compartment built for the waste may be analogous to the cytoplasm—the other organic material in the cell separated from the nucleus by the nuclear membrane. The third compartment was also separated from the upper two by a floor.
Eukaryotic cells, like all cells, are surrounded by a membrane. The membrane of a eukaryotic cell has a plasma membrane (similar to prokaryotic cells). It may or may not have cell walls (which are always present in prokaryotic cells). When G‑d told Noah to build the ark, He instructed Noah to build the ark with gopher wood and to cover it with pitch. Thus, the ark is a type of a cell with a wall (represented in the ark by the walls built of acacia wood) and a plasma membrane (represented in the ark by the tar that coated the walls).
All eukaryotic cells have mitochondria—the powerhouse that generates energy that feeds all metabolic processes in the cell. Similarly, Noah was commanded to store food in the ark to feed its inhabitants:
And take thou unto thee of all food that is eaten, and gather it to thee; and it shall be for food for thee, and for them. (Genesis 6:21)
Just as a living cell contains all genetic material (genes) necessary for the continuation of life, so too Noah’s ark housed every species of flora and fauna necessary to rebuild biological life on Earth after the flood. In this sense, Noah, his family members, and all animals represent the genes that make up the cell’s deoxyribonucleic acid (DNA). Just as the DNA of eukaryotic cells is double-stranded, which means that each gene comes in a pair (usually, one inherited from the mother and the other from the father), so too all humans and animals in the ark came in pairs—“two of every sort . . . male and female.”
One of the main functional characteristics of living cells (as of all living organisms) is the ability to maintain homeostasis—the steady state of equilibrium that maintains optimal physical and chemical conditions inside the cell. Chasidic teachings suggest that the ark was a prototype of a messianic society when “the wolf shall dwell with the lamb, and the leopard shall crouch with the kid” (Isaiah 11:6). Animals that usually prey on each other in the wild peacefully coexisted inside the ark, where there was peace and equilibrium that parallel to homeostasis in biology.
Needless to say, this structural parallel is far from literal and can hardly be extended to every detail. Nevertheless, on a high level, the parallel is remarkable. It is hardly coincidental considering that the Torah depicts Noah’s ark as a unit of life contained in the tevah (ark), which is emblematic of a living cell contained in the cell’s membrane.
 Historically, cells were discovered in 1665 by Robert Hooke, who named them for their resemblance to monastery cells. Noah’s ark bears some resemblance to a monastery cell as well, because it was small and because its inhabitants—both human and animal—had to practice sexual abstinence.
 Likkutei Sichot, vol. 25, pp. 29–30.