Class 12 Biology Chapter 23 Notes

• Important  chapter 23 biology class 12 mcqs for Intermediate part-II students.
• What is gene pharming?
• What is cystic fibrosis?
• What is meant by cloning?
• What are Palindromic sequences?
• Important chapter 23 biology class 12 short questions for Intermediate part-II students.
• What are the various methods of gene or DNA sequencing?
• What are the two goals of Human Genome Project?
• What is the biodegradable plastic and its origin?
• What is SCID? 
• What is the role of suicide gene in transgenic bacteria?
• What is the advantage of genetic engineering of C4 plants?
• What are transgenic plants. OR Give two advantages of transgenic plants. 
• What is Ex-vivo gene therapy? OR Differentiate between Ex-vivo and In-vivo gene therapy.
• What is a genome and genomic library? OR Differentiate between genome and genomic library. OR Define genomic library.
• What is PCR and write applications of PCR amplification. OR What are the uses of PCR amplification and analysis?
• Important class 12 biology chapter 23 important long questions for Intermediate part-II students.
• What is totipotency? OR What is totipotent cell? OR Define the term totipotent. OR Why plant cells are said to be totipotent?
• Define biotechnology. Give its application.
• Define Molecular scissors. OR What are restriction enzymes? Give example. OR Differentiate between molecular scissors and molecular vectors?
• Explain the importance of gene sequencing.
• Give the process of coronary artery ‘angioplasty’ briefly, using biotechnology.
• Important chapter 9 biology class 12 notes for Intermediate part-II students.
• Give any two requirements to produce recombinant DNA.
• What are protoplasts? Give scientific name of biodegradable plastic.

• Which enzyme is Taq polymerase?  DNA polymerase used is temperature - insensitive (thermostable) extracted from the bacterium Thermus aquaticus, which lives in hot springs. Commonly, this enzyme is known as Taq polymerase.
• How transgenic animals are developed?  Techniques have been developed to insert genes into the eggs of animals. It is possible to micro inject foreign genes into eggs by hand, but another method uses vortex mixing. The eggs are placed in an agitator with DNA and silicon - carbide needles, and the needles make tiny holes through which the DNA can enter. When these eggs are fertilized, the resulting offsprings are transgenic animals.
• Important chapter 9 biology class 12 questions and answers for Intermediate part-II students.
• How transgenic animals that secrete a product are often cloned?  After enucleated eggs have been injected with 2n nuclei of adult cells, they can be coaxed (persuaded or induced gradually) to begin development. The offspring have the genotype and phenotype of the adult that donated the nuclei; therefore, the adult has been cloned.
• What are Palindromic sequences?  Bacteria produces a variety of such restriction enzymes, which cut the DNA at very specific sites characterized by specific sequence of four to six nucleotides arranged symmetrically in the reverse order. such sequences are known as palindromic sequences.
• Important chapter 9 biology class 12 important questions for Intermediate part-II students.
• What are plasmids?  Plasmids are natural extra chromosomal circular DNA molecules which carry genes for antibiotic resistance and fertility etc. One of the plasmids discovered earlier PSC 101 has antibiotic resistance gene for tetracycline, whereas PSR 322 has antibiotic resistance genes for tetracycline as well as ampicillin.
• Where from PCR took its name?  Why is called chain reaction?  PCR takes its name from DNA polymerase, the enzyme that carries out DNA replication in a cell. It is considered a chain reaction because DNA polymerase will carry out replication over and over again, until there are millions of copies of the desired DNA.
• Important chapter 9 biology class 12 exercies questions for Intermediate part-II students.
• What is gene sequencing?  In DNA or gene sequencing, scientists create many copies of a single-stranded DNA fragment that will be used to synthesize a new DNA strand. Then these will be used to determine sequence of nucleotides.
• Important class 12 chapter 9 biology notes for Intermediate part-II students.