BIO 203 SDSU Exam 4 Correctly Solved!!

How did evidence from the study of metabolic defects contribute to the fundamental relationship between genes and proteins? - ANSWER -Garrod suggested that genes dictate phenotypes through enzymes that catalyze specific chemical reactions -Symptoms of an inherited disease reflected inability to synthesize a certain enzyme. -Linking genes to enzymes required understanding that cells synthesize and degrade molecules in a series of steps called the metabolic pathway. Describe the experiment by Beadle and Tatum which helped to develop the one gene - one enzyme hypothesis. - ANSWER Beadle and Tatum exposed bread mold to x-rays creating mutants that were unable to survive on minimal media. Developed a hypothesis, a one gene-one enzyme hypothesis stating that each gene dictates production of a specific enzyme. Why has the one gene - one enzyme hypothesis been restated to be more accurate? - ANSWER because not all proteins are enzymes and many proteins are composed of several polypeptides each of which has its own gene. Describe the basic principles of transcription and translation. - ANSWER Transcription- Synthesis of RNA using information in DNA. Produces mRNA. Translation-the synthesis of a polypeptide using information in the mRNA. Ribosomes are the sites of translation. (RNA flows from mRNA to protein through translation with help of tRNA)