2nd Year Biology Chapter 20 Notes

• Important 2nd year biology chapter 20 mcqs for Intermediate part-II students.
• 1. The enzyme which joins the two pieces of DNA is:  (A) endonuclease  (B) DNA polymerase  (C) Restriction  (D) DNA ligase
• 2. Which strand of DNA elongates towards the replication fork?  (A) Parental strand  (B) Leading strand  (C) Lagging strand  (D) Sense strand
• 3. Beadle and Tatum exposed Neurospora spores to:  (A) Alpha rays  (B) X - rays  (C) Gamma - rays  (D) Beta rays
• Important 2nd Year Biology Chapter 20 important questions for Intermediate part-II students.
• 4. RNA polymers I is used for the synthesis of:  (A) rRNA  (B) mRNA  (C) tRNA   (D) DNA
• 5. Human cells contain type of rRNA molecules:  (A) 20  (B) 45  (C) 195  (D) 204
• 6. Copying of mRNA from DNA is called:  (A) Trnaslation  (B) Transduction  (C) Transcription  (D) Transformation
• 7. mRNA is synthesized by:  (A) DNA polymerase  (B) RNA polymerase  (C) RNA ligase  (D) Endonuclease
• Important 2nd Year Biology Chapter 20 important short questions for Intermediate part-II students.

• Who first observe the chromosomes?
• What is transformation? What is nuclein?
• What is semi-conservative replication?
• How DNA polymerase III can initiate synthesis of DNA?
• What are Okazaki frangments?
• What is the length of Okazaki fragments?
• Important 2nd Year Biology Chapter 20 important long questions for Intermediate part-II students.
• What is "one gene or one polypeptide"?
•  What is transcription?
• Which codons are called stop codons and nonsense condon and why?
• What is initiation condon?
• How long DNA would stretch, if the DNA all of the cells of an adult human were lined up end to end?
• Important  Chapter 20 biology 2nd Year for Intermediate part-II students.
• What are the three major classes of RNA?
• What is the function of RNA polymerase in transcription?
• What are chromosomes? 
• What is the number of chromosomes in Penicillium and ferns?
• What a typical chromosome is made up of?
• What is Karyotype?
• What are different types of Chromosomes depending upon location of centromere?
• What are different shapes of chromosomes?
• What is the composition of chromosomes?
• How many nucleotides are contained in a typical human chromosome?
  
• How much information is contained in one chromosome?
• What is the length of a strand of DNA from a single chromosome?
• Why histones are positively charged? 
• What are supercoils of DNA?
• What are heterochromatin?
• Define the chromosome theory of inheritance?
• Who repeated the experiments of Griffith?
• Why Hershey and Chase are famous for?
• What are the main components of DNA?
• What is the structure of a typical nucleotide?
• What is phosphodiester bond or linkage?
• What is the work of Chargaff?
• What is X-ray diffraction?
• Who prepared the X-ray diffraction of DNA?
• What does X-ray diffraction of DNA suggest? 
  
• Who proposed the double helical structure of DNA? 
• Define replication. What is the Semi-conservative replication of DNA? 
• Define Conservative Replication of DNA.
• What is Dispersive Replication of DNA?
• What was work of Meselson - Stahl?
• What is the role of DNA polymerase I? 
• What is the role of DNA polymerase II?
• What is the role of DNA polymerase III?
• hat is the direction of replication on growing DNA strand?
• What is the role of DNA ligase?  What is Alkaptonuria?
• Why Beadle and Tatum are famous for?
• Why Sanger was famous for?
• Why Vernon Ingram is famous for?
• What is Promotor?
• What is translation.?
• What are template and coding strands of DNA?
• What is the role of RNA polymerase?
• How many binding sites are found in in promoter of prokaryote and eukaryote?
• What is the stop signal for transcription?     Why a cap and a tail is added to mRNA?
• Important long question of Biology 2nd year chapter 20