TRB PG Assistant - Modern gene concepts – cistron, muton, recon Online Test (MCQ Quiz)

1. Which of the following represents the smallest functional unit of genetic material that can undergo recombination?

A) Cistron B) Muton C) Recon D) Operon

2. The unit of genetic material that determines a single polypeptide chain or a functional RNA molecule is known as:

A) Muton B) Recon C) Cistron D) Induction

3. What genetic unit is defined by its ability to cause a mutation?

A) Cistron B) Recon C) Muton D) Episome

4. Seymour Benzer's experiments in the 1950s were crucial in defining which genetic concepts?

A) Gene pool and genetic drift B) Cistron, muton, and recon C) Linkage and crossing over D) Central dogma of molecular biology

5. If a mutation occurs and is then reverted by another mutation at the same site, restoring the original phenotype, the smallest unit involved in this process is the:

A) Cistron B) Recon C) Muton D) Splicing unit

6. A 'cistron' is functionally equivalent to a:

A) Recombination site B) Mutation site C) Gene D) Regulatory element

7. The concept of 'muton' is based on the smallest unit of genetic material that can be changed by a:

A) Recombination event B) Mutation C) Transcription event D) Translation event

8. In the context of gene concepts, 'recon' refers to the smallest segment of DNA involved in:

A) Mutation B) Recombination C) Gene expression D) Protein synthesis

9. Which of the following statements accurately describes the relationship between cistron, muton, and recon?

A) Cistron is the largest, containing mutons and recons B) Muton is the largest, containing cistrons and recons C) Recon is the largest, containing cistrons and mutons D) They are independent units with no hierarchical relationship

10. A single nucleotide change within a DNA sequence can alter the function of a gene. This smallest unit of change corresponds to the:

A) Cistron B) Recon C) Muton D) Exon

11. The cis-trans test (or complementation test) is used to determine if two mutations are in the same:

A) Muton B) Recon C) Cistron D) Operon

12. If two different mutations within the same gene (cistron) are introduced into a diploid organism, and each mutation is recessive, they may complement each other if they are in different functional units. This phenomenon is related to:

A) Recombination B) Mutation rate C) Cistron definition D) Operon regulation

13. Which concept implies that a single DNA base pair change is the minimum unit that can be mutated?

A) Cistron B) Recon C) Muton D) Gene locus

14. The ability of two different mutations to restore a wild-type phenotype when they are present in the same cell (trans configuration) but not when they are on the same chromosome (cis configuration) helps define:

A) Muton B) Recon C) Cistron D) Alleles

15. A 'recombination' event between two closely linked mutations within a functional gene (cistron) can restore the wild-type gene. The smallest unit demonstrating this recombination capability is the:

A) Muton B) Cistron C) Recon D) Polycistronic mRNA

16. The concept of the 'muton' is considered to be approximately equivalent to a:

A) Codon B) Single nucleotide C) Recombination site D) Functional RNA molecule

17. In molecular terms, a 'recon' is often considered to be the smallest segment of DNA that can undergo exchange during:

A) Mutation B) Transcription C) Recombination D) Translation

18. The 'cistron' concept is fundamentally linked to the idea of a gene specifying a:

A) Phenotypic trait B) Molecular product (protein or RNA) C) Regulatory sequence D) Chromosomal location

19. Which of the following is a limitation of the classical gene concepts (cistron, muton, recon) in understanding modern genetics?

A) They do not account for gene regulation B) They do not consider the molecular basis of heredity C) They do not explain gene linkage D) They are overly simplistic and do not fully capture the complexity of DNA and its functions

20. If a mutation changes a single base pair, and this change affects the protein product, the affected unit is the:

A) Cistron B) Muton C) Recon D) Intron

21. The 'muton' can be defined as the smallest unit of genetic material that, when altered, can lead to a change in:

A) Phenotype B) Recombination frequency C) Transcription rate D) Translation efficiency

22. Which unit is defined by the ability to undergo reciprocal exchange with another genetic unit?

A) Cistron B) Muton C) Recon D) Promoter

23. Benzer's experiments with bacteriophage T4 provided evidence for the distinction between:

A) Replication and transcription B) Mutation and recombination C) Cistrons, mutons, and recons D) Genes and chromosomes

24. A gene locus that can be mapped by recombination frequencies is related to the concept of:

A) Muton B) Cistron C) Recon D) Operon

25. The functional definition of a gene as a unit encoding a polypeptide or RNA is most closely aligned with the concept of:

A) Muton B) Recon C) Cistron D) Enhancer

26. If two mutations fail to complement in the trans configuration, it implies they are within the same:

A) Recon B) Muton C) Cistron D) Intergenic region

27. The concept of 'muton' emphasizes the smallest unit that can undergo alteration resulting in a:

A) Functional change in a protein B) Change in recombination pattern C) Change in gene dosage D) Change in chromosome structure

28. The 'recon' represents the smallest unit of genetic material capable of participating in:

A) Point mutation B) Gene duplication C) Homologous recombination D) Transposition

29. Which classical genetic unit is defined by its role in determining the phenotype of an organism?

A) Muton B) Recon C) Cistron D) Regulon

30. Benzer's fine-structure mapping experiments showed that a single gene (cistron) could be subdivided into smaller units of mutation and recombination. These units are the:

A) Operons and promoters B) Mutons and recons C) Introns and exons D) Telomeres and centromeres

31. If a single nucleotide is substituted, this event is best described as a change in the:

A) Cistron B) Recon C) Muton D) Gene cluster

32. The ability of two different DNA sequences to exchange genetic material between them defines the unit known as:

A) Cistron B) Muton C) Recon D) Operator

33. A 'cistron' is essentially a segment of DNA that codes for a single:

A) Ribosomal RNA B) Transfer RNA C) Polypeptide chain D) All of the above

34. Which of the following accurately represents the relative sizes of these genetic units from smallest to largest?

A) Cistron > Muton > Recon B) Muton > Recon > Cistron C) Recon < Muton < Cistron D) Muton = Recon < Cistron

35. The concept of 'muton' is directly related to the molecular basis of:

A) Gene conversion B) Point mutation C) Chromosomal aberration D) Epigenetic modification

36. The 'recon' is a unit of genetic material that can be exchanged between homologous chromosomes during:

A) Mitosis B) Meiosis C) DNA replication D) Protein synthesis

37. A functional gene, as understood in classical genetics and molecular biology, is best represented by the:

A) Muton B) Recon C) Cistron D) Intron

38. If a gene contains multiple sites where mutations can occur, and these sites can be separated by recombination, these sites are referred to as:

A) Cistrons B) Mutons C) Recons D) Exons

39. The 'muton' is the smallest unit that can mutate. This unit is often considered to be equivalent to a:

A) Gene B) Chromosome segment C) Nucleotide pair D) Recombination event

40. The cis-trans test, used to differentiate alleles and define functional units, is a direct application of the concept of:

A) Muton B) Recon C) Cistron D) Operon

41. Which genetic unit is defined by its ability to produce a functional product, such as a protein?

A) Muton B) Recon C) Cistron D) Promoter

42. The concept that a gene can be subdivided into regions that mutate independently and recombine independently led to the definitions of:

A) Operon and regulon B) Cistron, muton, and recon C) Replication and transcription D) DNA and RNA

43. A single base deletion or insertion within a DNA sequence represents a change at the level of the:

A) Cistron B) Recon C) Muton D) Gene locus

44. If two mutations are within the same cistron, they will generally:

A) Complement each other in the trans configuration B) Fail to complement each other in the trans configuration C) Always recombine to form a wild-type gene D) Be located on different chromosomes

45. The smallest unit of genetic material that can undergo crossing over is the:

A) Cistron B) Muton C) Recon D) Chromatid

46. The 'muton' is the fundamental unit of genetic change, responsible for:

A) Recombination B) Gene expression C) Mutation D) DNA repair

47. The 'cistron' concept revolutionized the understanding of genes by moving beyond a single unit for a trait to a unit encoding a specific:

A) Phenotype B) Biochemical pathway C) Molecular product D) Regulatory mechanism

48. In fine-structure mapping, the ability to map recombination events between closely located sites within a gene supports the concept of:

A) Muton B) Cistron C) Recon D) Operon

49. Which of the following is the most accurate hierarchical relationship?

A) A cistron is the smallest unit, containing mutons and recons. B) A recon is the smallest unit, and multiple recons form a muton, and multiple mutons form a cistron. C) A muton is the smallest unit, and multiple mutons form a recon, and multiple recons form a cistron. D) A cistron contains multiple mutons, and a muton contains multiple recons.

50. The 'muton' is the smallest unit of heredity that can undergo a change, leading to a different allele. This change is typically a:

A) Deletion of a large DNA segment B) Inversion of a chromosome arm C) Point mutation at the DNA level D) Translocation of genetic material

Modern gene concepts – cistron, muton, recon - Online Test

Test Results