Your cells contain two types of nucleic acids, ribonucleic acid and deoxyribonucleic acid, or RNA and DNA, respectively. They differ from the other macronutrients in that they are not a source of calories in your diet, and their role is strictly to direct the synthesis of new protein molecules.
Definition of postgraduate for English Language Learners. : a student who continues to study for an advanced degree after earning a bachelor's degree or other first degree : a graduate student.
As a general rule an undergraduate degree such as B.A. or BSc is a first degree usually taken after high school. The 'B' in B.A stands for Bachelor hence Bachelor of Arts or Bachelor of Science. A post graduate degree is a higher award usually taken after the bachelors degree. Some examples of post graduate degrres are: M.A (Master of Arts.) M.Sc (Master of Science) M.B.A (Master of Business Administration .) Sometimes the Master's degree is issued as a first degree, that is without taking a Bachelors first.