Yeast, a cellular model. Yeast is a simple living being that functions in practically the same way as human cells. It is an historical subject of fundamental research to understand cellular and genetic phenomena. It is a representative model of all eukaryotic cells.
Covenant. An agreement, contract, or written promise between two individuals that frequently constitutes a pledge to do or refrain from doing something. The individual making the promise or agreement is known as the covenantor, and the individual to whom such promise is made is called the covenantee.
Requirements. 1  The covenant must be in writing to satisfy the Statute of Frauds. 2  The original parties to the agreement must have intended that successors be bound by the agreement. 3  A subsequent owner must have had actual notice, inquiry notice, or constructive notice (record) of the covenant at the time of purchase.