Biology

Molecular Biology and Genetics

985 Questions

Molecular biology and genetics explore the structure and function of DNA, RNA, genetic mutations, and heredity. Understanding these building blocks of life is essential for most biology examinations. Review these practice questions to test your molecular genetics knowledge.

DNA structure and basesGenetic mutationsNucleic acids compositionDNA sequencing and replication

Molecular Biology and Genetics Questions

Multiple choice

Purines are comprised of

  1. Adenine and Guanine

  2. Adenine and thymine

  3. Cytosine and uracil

  4. Cytosine and thymine
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Adenine and Guanine

Multiple choice

Mathew, Meselson and Stahlin proved that

  1. DNA replicates by a semiconservative method

  2. DNA is a double -helical structure

  3. DNA is a coiled structure

  4. DNA ia the genetic material
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

DNA replicates by semiconservative method

Multiple choice

The nucleoside molecule consists of a

  1. pentose sugar and a phosphate group

  2. Phosphate group and nitrogenous base

  3. Pentose sugar and nitrogenous base

  4. pentose sugar, nitrogenous base and phosphate group
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

pentose sugar and nitrogenous base

Multiple choice

Which of the following is found only in RNA but not in DNA?

  1. Adenine

  2. Thymine

  3. Guanine

  4. Uracil
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Uracil base is found only in RNA and thymine base is found only in DNA whereas adenine, guanine and cytosine bases are common in both DNA and RNA. DNA contain deoxyribose sugar instead of ribose sugar in RNA. 

Multiple choice

Defect in amino acid metabolism may result in

  1. albinism

  2. porphyria

  3. Wilson's disease

  4. phenylketonuria
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Phenylketonuria is disorder caused by the defect in amino acid metabolism. Children suffering with phenylketonuria are unable to breakdown phenyl pyruvic acid into hydroxyl phenyl pyruvic acid. Accumulation of phenyl pyruvic acid causes mental disorder.