1. Genetics is the study of:
(A) Evolution
(B) Heredity and variation
(C) Ecology
(D) Development
2. Who is known as the father of genetics?
(A) Darwin
(B) Morgan
(C) Mendel
(D) Watson
3. Mendel performed his experiments on:
(A) Wheat
(B) Maize
(C) Rice
(D) Pea plant
4. The term gene was introduced by:
(A) Mendel
(B) De Vries
(C) Johannsen
(D) Morgan
5. The observable traits of an organism are called:
(A) Genotype
(B) Genome
(C) Alleles
(D) Phenotype
6. The genetic makeup of an organism is known as:
(A) Phenotype
(B) Genotype
(C) Chromosome
(D) Trait
7. Alternative forms of a gene are called:
(A) Loci
(B) Chromatids
(C) Alleles
(D) Genomes
8. Mendel’s law of segregation states that:
(A) Genes blend
(B) Alleles separate during gamete formation
(C) Traits are linked
(D) Genes mutate
9. Mendel’s law of independent assortment applies to genes located on:
(A) Same chromosome
(B) Linked genes
(C) Different chromosomes
(D) Sex chromosomes
10. The phenotypic ratio of a monohybrid cross is:
(A) 1:1
(B) 1:2:1
(C) 9:3:3:1
(D) 3:1
11. A dihybrid cross gives a phenotypic ratio of:
(A) 3:1
(B) 1:2:1
(C) 1:1
(D) 9:3:3:1
12. A homozygous genotype has:
(A) Two different alleles
(B) One allele
(C) No alleles
(D) Two identical alleles
13. Which genotype is heterozygous?
(A) Aa
(B) aa
(C) BB
(D) AA
14. A test cross is carried out between:
(A) Two dominant individuals
(B) Two recessive individuals
(C) Two hybrids
(D) Hybrid and homozygous recessive
15. The unit of inheritance is called:
(A) Chromosome
(B) Gene
(C) DNA
(D) Nucleotide
16. Crossing over occurs during:
(A) Prophase I
(B) Metaphase I
(C) Anaphase I
(D) Telophase I
17. The chromosomal theory of inheritance was proposed by:
(A) Sutton and Morgan
(B) Watson and Crick
(C) Darwin
(D) Mendel
18. The position of a gene on a chromosome is called:
(A) Genome
(B) Allele
(C) Chromatid
(D) Locus
19. Sex-linked traits are located on:
(A) Sex chromosomes
(B) Mitochondria
(C) Ribosomes
(D) Autosomes
20. Color blindness is an example of:
(A) Autosomal dominant
(B) X-linked recessive
(C) Autosomal recessive
(D) Y-linked
21. The genetic material in most organisms is:
(A) RNA
(B) Protein
(C) DNA
(D) Lipid
22. A sudden heritable change is called:
(A) Mutation
(B) Adaptation
(C) Variation
(D) Recombination
23. Which scientist discovered linkage?
(A) Mendel
(B) Watson
(C) Crick
(D) Morgan
24. Genes located close together on the same chromosome show:
(A) Independent assortment
(B) Linkage
(C) Polygenic inheritance
(D) Codominance
25. The number of chromosomes in human somatic cells is:
(A) 23
(B) 44
(C) 48
(D) 46
26. Trisomy 21 causes:
(A) Turner syndrome
(B) Down syndrome
(C) Edwards syndrome
(D) Klinefelter syndrome
27. Which inheritance shows blending of traits?
(A) Incomplete dominance
(B) Codominance
(C) Complete dominance
(D) Sex linkage
28. ABO blood groups are an example of:
(A) Polygenic inheritance
(B) Incomplete dominance
(C) Sex linkage
(D) Codominance
29. Multiple genes controlling a single trait is known as:
(A) Polygenic inheritance
(B) Mutation
(C) Linkage
(D) Pleiotropy
30. One gene affecting multiple traits is called:
(A) Polygenic inheritance
(B) Codominance
(C) Pleiotropy
(D) Linkage
31. Which phase shows maximum chromosome condensation?
(A) Metaphase
(B) Prophase
(C) Anaphase
(D) Telophase
32. The pairing of homologous chromosomes is called:
(A) Chiasma
(B) Crossing over
(C) Tetrad
(D) Synapsis
33. Which structure holds sister chromatids together?
(A) Telomere
(B) Chromatin
(C) Kinetochore
(D) Centromere
34. Which chromosome determines male sex in humans?
(A) X chromosome
(B) Y chromosome
(C) Autosomes
(D) Z chromosome
35. Turner syndrome individuals have:
(A) 44 + XY
(B) 45 chromosomes
(C) 44 + XX
(D) 47 chromosomes
36. Klinefelter syndrome has genotype:
(A) XO
(B) XXX
(C) XYY
(D) XXY
37. The exchange of genetic material occurs between:
(A) Non-sister chromatids
(B) Sister chromatids
(C) Autosomes
(D) Sex chromosomes
38. Which inheritance is controlled by many genes?
(A) Monogenic
(B) Polygenic
(C) Digenic
(D) Sex-linked
39. A cross involving two traits is called:
(A) Test cross
(B) Back cross
(C) Monohybrid cross
(D) Dihybrid cross
40. The complete set of chromosomes is called:
(A) Phenotype
(B) Gene pool
(C) Genotype
(D) Genome
41. Which molecule carries genetic information?
(A) Protein
(B) RNA
(C) Lipid
(D) DNA
42. RNA differs from DNA by having:
(A) Thymine
(B) Uracil
(C) Deoxyribose sugar
(D) Double strand
43. Which base pairing occurs in DNA?
(A) A–C
(B) G–T
(C) A–U
(D) A–T
44. The process of copying DNA is called:
(A) Translation
(B) Transcription
(C) Replication
(D) Mutation
45. Messenger RNA carries information from:
(A) Cytoplasm to ribosome
(B) Nucleus to ribosome
(C) Ribosome to nucleus
(D) Ribosome to cytoplasm
46. Which scientist proposed the double helix model of DNA?
(A) Mendel
(B) Morgan
(C) Watson and Crick
(D) Franklin
47. A change in chromosome number is called:
(A) Mutation
(B) Recombination
(C) Polyploidy
(D) Aneuploidy
48. Which type of RNA forms ribosomes?
(A) rRNA
(B) tRNA
(C) mRNA
(D) snRNA
49. Which inheritance pattern is seen in sickle cell anemia?
(A) Dominant
(B) Recessive
(C) Codominant
(D) Sex-linked
50. The physical carrier of genes is:
(A) Chromosome
(B) Ribosome
(C) Protein
(D) Cytoplasm