Class 12th Biology 2016 Set1 Outside Delhi Board Paper Solution
Question 18
Why is the coding sequence of an enzyme ( β -galactosidase) a preferred selectable marker in comparison to the ones named above ?
Answer
Alternative selectable marker which differentiate recombinants from non-recombinants on the basis of their ability to produce colour in the presence of a chromogenic substrate. In this , a recombinant DNA is . inserted within the coding sequence of an enzyme, b galactosidase, which results into activation of the enzyme referred as insertional inactivation coding sequence for the enzyme b-galactosidase is preferred over antibiotic resistance genes because recombinants can be easily visualised.
Popular Questions of Class 12th biology
- Q:- What is spermatogenesis? Briefly describe the process of spermatogenesis.
- Q:- Why is reproduction essential for organisms? Answer
- Q:- Write a short note on
(a) Adaptations of desert plants and animals
(b) Adaptations of plants to water scarcity
(c) Behavioural adaptations in animals
(d) Importance of light to plants
(e) Effect of temperature or water scarcity and the adaptations of animals. - Q:- With a neat diagram explain the 7-celled, 8-nucleate nature of the female gametophyte.
- Q:- What is DNA fingerprinting? Mention its application.
- Q:- What is oogenesis? Give a brief account of oogenesis.
- Q:- Describe the structure of a seminiferous tubule.
- Q:- What is triple fusion? Where and how does it take place? Name the nuclei involved in triple fusion.
- Q:- With a neat, labelled diagram, describe the parts of a typical angiosperm ovule.
- Q:- Explain the Law of Dominance using a monohybrid cross.
Recently Viewed Questions of Class 12th biology
- Q:- What is vegetative propagation? Give two suitable examples.
- Q:- Which one of the following has the largest population in a food chain?
(a) Producers
(b) Primary consumers
(c) Secondary consumers
(d) Decomposers - Q:- Give examples to prove that microbes release gases during metabolism.
- Q:- Differentiate between gametogenesis from embryogenesis.
- Q:- Find out from internet what is golden rice.
- Q:- Arrange the following terms in the correct developmental sequence:
- Q:- Give an example for:
(a) An endothermic animal
(b) An ectothermic animal
(c) An organism of benthic zone - Q:- Most living organisms cannot survive at temperature above 45°C°. How are some microbes able to live in habitats with temperatures exceeding 100°C?
- Q:- If your family owned a dairy farm, what measures would you undertake to improve the quality and quantity of milk production?
- Q:- Two heterozygous parents are crossed. If the two loci are linked what would be the distribution of phenotypic features in F1 generation for a dihybrid cross?