Genetics questions

Question 1

What is the basic unit of heredity?
o A. Protein
o B. RNA
o C. Gene
o D. Chromosome

Answer 1

o C. Gene

Question 2

Which molecule carries the genetic instructions in most living organisms?
o A. DNA
o B. RNA
o C. Protein
o D. Lipid

Answer 2

o A. DNA

Question 3

Which process results in the formation of two identical daughter cells?
o A. Meiosis
o B. Mitosis
o C. Binary fission
o D. Crossing over

Answer 3

o B. Mitosis

Question 4

Who is known as the father of genetics?
o A. Charles Darwin
o B. Gregor Mendel
o C. James Watson
o D. Francis Crick

Answer 4

o B. Gregor Mendel

Question 5

Which nitrogenous base is not found in RNA?
o A. Adenine
o B. Thymine
o C. Cytosine
o D. Uracil

Answer 5

o B. Thymine

Question 6

What is the chromosomal theory of inheritance?
o A. Genes are located on chromosomes
o B. Genes are made of proteins
o C. Genes control all cell functions
o D. Genes are found in the cytoplasm

Answer 6

o A. Genes are located on chromosomes

Question 7

During which phase of mitosis do the chromosomes line up in the middle of the cell?
o A. Prophase
o B. Metaphase
o C. Anaphase
o D. Telophase

Answer 7

o B. Metaphase

Question 8

What is the purpose of crossing over during meiosis?
o A. To replicate DNA
o B. To produce gametes
o C. To increase genetic diversity
o D. To create identical daughter cells

Answer 8

o C. To increase genetic diversity

Question 9

Which type of RNA carries the genetic code from DNA to the ribosome?
o A. tRNA
o B. mRNA
o C. rRNA
o D. miRNA

Answer 9

o B. mRNA

Question 10

What are histones?
o A. Enzymes that replicate DNA
o B. Proteins that package DNA into nucleosomes
o C. RNA molecules involved in translation
o D. Lipids that form the cell membrane

Answer 10

o B. Proteins that package DNA into nucleosomes

Question 11

Which scientist(s) discovered the structure of DNA?
o A. Watson and Crick
o B. Mendel
o C. Darwin
o D. Hershey and Chase

Answer 11

o A. Watson and Crick

Question 12

What is the function of restriction enzymes in genetic engineering?
o A. To replicate DNA
o B. To cut DNA at specific sequences
o C. To transcribe RNA
o D. To translate proteins

Answer 12

o B. To cut DNA at specific sequences

Question 13

Which phase of meiosis includes crossing over?
o A. Metaphase I
o B. Anaphase I
o C. Prophase I
o D. Telophase I

Answer 13

o C. Prophase I

Question 14

What are complementary base pairs in DNA?
o A. A-T and C-G
o B. A-G and C-T
o C. A-C and G-T
o D. A-U and C-G

Answer 14

o A. A-T and C-G

Question 15

Which enzyme is responsible for adding nucleotides during DNA replication?
o A. Helicase
o B. DNA polymerase
o C. RNA polymerase
o D. Ligase

Answer 15

o B. DNA polymerase

Question 16

What does “epistasis” refer to in genetics?
o A. A gene interaction where one gene masks the effect of another
o B. The expression of two dominant alleles
o C. The recombination of genes during crossing over
o D. The transcription of mRNA from DNA

Answer 16

o A. A gene interaction where one gene masks the effect of another

Question 17

Which genetic disorder is caused by a trisomy of chromosome 21?
o A. Turner syndrome
o B. Klinefelter syndrome
o C. Down syndrome
o D. Patau syndrome

Answer 17

o C. Down syndrome

Question 18

What is the role of mRNA in protein synthesis?
o A. It transports amino acids to the ribosome
o B. It carries the genetic code from DNA to the ribosome
o C. It forms the structure of the ribosome
o D. It catalyzes the formation of peptide bonds

Answer 18

o B. It carries the genetic code from DNA to the ribosome

Question 19

Which structure is involved in the regulation of gene expression through histone
modification?
o A. Promoter
o B. Enhancer
o C. Nucleosome
o D. Exon

Answer 19

o C. Nucleosome

Question 20

What is the difference between leading and lagging strands in DNA replication?
o A. The leading strand is synthesized continuously, while the lagging strand is synthesized in fragments
o B. The leading strand is synthesized in the 3’ to 5’ direction, while the lagging strand is synthesized in the 5’ to 3’ direction
o C. The leading strand is made of RNA, while the lagging strand is made of DNA
o D. The leading strand forms first, while the lagging strand forms later

Answer 20

o A. The leading strand is synthesized continuously, while the lagging strand is synthesized in fragments

Question 21

What is a karyotype?
o A. A chart showing the sequence of genes on a chromosome
o B. A diagram representing the physical structure of a gene
o C. A profile of an individual’s chromosomes arranged by size and shape
o D. A type of genetic mutation

Answer 21

o C. A profile of an individual’s chromosomes arranged by size and shape

Question 22

Which type of RNA is involved in the splicing of pre-mRNA?
o A. tRNA
o B. rRNA
o C. snRNA
o D. miRNA

Answer 22

o C. snRNA

Question 23

Which genetic phenomenon is described by the phrase “one gene-one enzyme”?
o A. Each gene codes for a single protein
o B. Each gene is responsible for one metabolic pathway
o C. Each gene codes for one enzyme that affects multiple traits
o D. Each gene is linked to one specific disease

Answer 23

o A. Each gene codes for a single protein

Question 24

What is a Barr body?
o A. An inactivated X chromosome in female mammals
o B. A type of RNA molecule
o C. A protein involved in DNA replication
o D. A gene that regulates apoptosis

Answer 24

o A. An inactivated X chromosome in female mammals

Question 25

Which process increases genetic diversity during meiosis? o A. DNA replication o B. Chromosome segregation o C. Independent assortment o D. DNA repair

Answer 25

o C. Independent assortment

Question 26

Which genetic disorder is caused by a point mutation in the CFTR gene? o A. Sickle cell anemia o B. Cystic fibrosis o C. Hemophilia o D. Duchenne muscular dystrophy

Answer 26

o B. Cystic fibrosis

Question 27

What is the function of telomerase? o A. It synthesizes telomeres at the ends of chromosomes o B. It repairs mismatched DNA o C. It unwinds the DNA double helix o D. It joins Okazaki fragments on the lagging strand

Answer 27

o A. It synthesizes telomeres at the ends of chromosomes

Question 28

Which enzyme is involved in the transcription of RNA from a DNA template? o A. DNA polymerase o B. RNA polymerase o C. Helicase o D. Ligase

Answer 28

o B. RNA polymerase

Question 29

What is the role of homeotic genes in development? o A. They determine the identity of body segments o B. They regulate cell cycle progression o C. They code for structural proteins o D. They protect the genome from mutations

Answer 29

o A. They determine the identity of body segments

Question 30

What is the Hardy-Weinberg equilibrium? o A. A state in which allele frequencies in a population remain constant over time o B. A state in which all individuals in a population have the same genotype o C. A measure of genetic diversity in a population o D. A method for determining the sequence of a DNA molecule

Answer 30

o A. A state in which allele frequencies in a population remain constant over time

Question 31

What is the primary function of the long non-coding RNAs (lncRNAs) in gene regulation? * A. To code for proteins * B. To serve as templates for mRNA * C. To regulate gene expression at the transcriptional and post-transcriptional levels * D. To assist in DNA replication

Answer 31

* C. To regulate gene expression at the transcriptional and post-transcriptional levels

Question 32

In the context of mitochondrial inheritance, which statement is true? * A. Mitochondrial DNA is inherited equally from both parents * B. Mitochondrial DNA is inherited only from the mother * C. Mitochondrial DNA undergoes recombination * D. Mitochondrial DNA is inherited only from the father

Answer 32

* B. Mitochondrial DNA is inherited only from the mother

Question 33

What is the key characteristic of transposons that differentiates them from other genetic elements? * A. Their ability to be transcribed into mRNA * B. Their ability to replicate independently of the host genome * C. Their ability to move from one location to another within the genome * D. Their role in protein synthesis

Answer 33

* C. Their ability to move from one location to another within the genome

Question 34

Which genetic phenomenon describes a situation where one gene influences multiple phenotypic traits? * A. Epistasis * B. Pleiotropy * C. Polygenic inheritance * D. Co-dominance

Answer 34

* B. Pleiotropy

Question 35

In genetic mapping, what does a recombination frequency of 50% indicate? * A. The genes are located on the same chromosome very close to each other * B. The genes are located on different chromosomes * C. The genes are very far apart on the same chromosome or on different chromosomes * D. The genes are tightly linked

Answer 35

* C. The genes are very far apart on the same chromosome or on different chromosomes

Question 36

Which type of mutation is characterized by the expansion of nucleotide repeat sequences? * A. Point mutation * B. Deletion mutation * C. Dynamic mutation * D. Inversion mutation

Answer 36

* C. Dynamic mutation

Question 37

What is the primary purpose of using fluorescent in situ hybridization (FISH) in genetic analysis? * A. To sequence DNA * B. To amplify DNA fragments * C. To detect and localize the presence or absence of specific DNA sequences on chromosomes * D. To separate DNA fragments based on size

Answer 37

* C. To detect and localize the presence or absence of specific DNA sequences on chromosomes

Question 38

What is the defining feature of quantitative trait loci (QTL)? * A. They code for a single gene that controls a trait * B. They are regions of the genome that contribute to the variation in a quantitative trait * C. They are genetic markers that indicate the presence of a specific trait * D. They are loci that do not recombine during meiosis

Answer 38

* B. They are regions of the genome that contribute to the variation in a quantitative trait

Question 39

In the context of epigenetics, what is the primary role of DNA methylation? * A. To increase the rate of DNA replication * B. To promote gene expression * C. To silence gene expression * D. To facilitate DNA repair

Answer 39

* C. To silence gene expression

Question 40

What is the function of telomerase? * A. It synthesizes telomeres at the ends of chromosomes * B. It repairs mismatched DNA * C. It unwinds the DNA double helix * D. It joins Okazaki fragments on the lagging strand

Answer 40

* A. It synthesizes telomeres at the ends of chromosomes