An isthmus is a land bridge bordered on both sides by water that connects two larger bodies of land. A narrow strip of land with sea on either side. (dictionary.com) An Isthmus is a narrow strip of land connecting two larger land areas usually with water on either side. Of note, the Isthmus of Corinth connects the peninsula of Peloponnese with the rest of the Greek peninsula, the Isthmus of Panama connects the continents of North and South America (the Americas), and the Isthmus of Suez in Egypt connects Africa and Asia (or Eurasia).
straight bond. Definition. Bond which will pay back the principal on its maturity date, will pay a specified amount of interest on specific dates, and does not carry a conversion privilege or other special features.
Single bonds are a type of covalent bond formed from the sharing of two electrons between two atoms, one electron from each atom. Now this is quite different from double bonds. Double bonds are a type of covalent bond where four electrons are shared between two atoms. This leads us to the last type of bond, a triple bond. A triple bond is a type of covalent bond where six electrons are shared between two atoms.