Cell Biology & Genetics MCQs 2026

What is the term for a permanent change in an organism's DNA sequence

1. AMutation✓
2. BTranscription✓
3. CTranslation✓
4. DMeiosis✓

Who is regarded as the "Father of Modern Genetics" for his pea plant experiments establishing basic inheritance laws

1. ACharles Darwin✓
2. BGregor Mendel✓
3. CJames Watson✓
4. DFrancis Crick✓

What term describes an organism's observable physical characteristics, resulting from genetic and environmental factors

1. AGenotype✓
2. BPhenotype✓
3. CAllele✓
4. DLocus✓

What term describes an organism's specific genetic makeup for a particular trait

1. AGenotype✓
2. BPhenotype✓
3. CAllele✓
4. DLocus✓

What term describes alternative forms of a gene that can exist at a specific location on a chromosome

1. AGenotype✓
2. BPhenotype✓
3. CAllele✓
4. DLocus✓

What term describes a trait that is expressed even when only one copy of the responsible allele is present

1. ARecessive trait✓
2. BDominant trait✓
3. CCodominant trait✓
4. DSex-linked trait only✓

What is the basic structural and functional unit of all living organisms

1. AAtom✓
2. BCell✓
3. CMolecule✓
4. DTissue✓

Which part of the cell contains genetic material and controls cell activities

1. AMitochondria✓
2. BNucleus✓
3. CRibosome✓
4. DCell membrane✓

Which cell organelle is known as the "powerhouse of the cell," responsible for energy production

1. ANucleus✓
2. BMitochondria✓
3. CRibosome✓
4. DGolgi apparatus✓

Which cell structure is responsible for protein synthesis

1. ANucleus✓
2. BMitochondria✓
3. CRibosome✓
4. DLysosome✓

Which cell organelle modifies, sorts, and packages proteins for secretion or use within the cell

1. ANucleus✓
2. BGolgi apparatus✓
3. CRibosome✓
4. DMitochondria✓

Which cell organelle contains digestive enzymes to break down waste materials and cellular debris

1. ANucleus✓
2. BLysosome✓
3. CRibosome✓
4. DGolgi apparatus✓

Which structure surrounds and protects the cell, regulating what enters and exits

1. ACell wall (plants only)✓
2. BCell membrane✓
3. CNucleus✓
4. DCytoplasm✓

Which structure, found in plant cells but not animal cells, provides rigid structural support

1. ACell membrane✓
2. BCell wall✓
3. CNucleus✓
4. DCytoplasm✓

Which type of cell lacks a true nucleus and membrane-bound organelles, such as bacteria

1. AEukaryotic cell✓
2. BProkaryotic cell✓
3. CPlant cell✓
4. DAnimal cell✓

Which type of cell has a true, membrane-bound nucleus and organelles, such as plant and animal cells

1. AProkaryotic cell✓
2. BEukaryotic cell✓
3. CBacterial cell only✓
4. DViral cell✓

Which organelle, found in plant cells, contains chlorophyll and conducts photosynthesis

1. AMitochondria✓
2. BChloroplast✓
3. CRibosome✓
4. DLysosome✓

What is the term for the jelly-like substance filling the cell, in which organelles are suspended

1. ANucleus✓
2. BCytoplasm✓
3. CCell wall✓
4. DChromatin✓

What is the molecule that carries genetic information in all living organisms

1. ADNA✓
2. BRNA✓
3. CProtein✓
4. DATP✓

What shape does the DNA molecule characteristically form

1. ASingle strand✓
2. BDouble helix✓
3. CTriple helix✓
4. DCircular loop only✓

What are the four nitrogenous bases found in DNA

1. AAdenine, Guanine, Cytosine, Thymine✓
2. BAdenine, Guanine, Cytosine, Uracil✓
3. CAdenine, Thymine, Uracil, Guanine✓
4. DCytosine, Guanine, Uracil, Thymine✓

Which nitrogenous base found in RNA replaces Thymine, which is found in DNA

1. AAdenine✓
2. BGuanine✓
3. CCytosine✓
4. DUracil✓

What is the term for a segment of DNA that codes for a specific protein or trait

1. AChromosome✓
2. BGene✓
3. CRibosome✓
4. DNucleotide✓

What is the term for the thread-like structures made of tightly coiled DNA, found within the nucleus

1. AGenes✓
2. BChromosomes✓
3. CRibosomes✓
4. DNucleotides✓

How many chromosomes are typically found in a normal human somatic (body) cell

1. A23✓
2. B44✓
3. C46✓
4. D48✓

How many pairs of chromosomes are found in a normal human somatic cell

1. A21 pairs✓
2. B22 pairs✓
3. C23 pairs✓
4. D24 pairs✓

How many chromosomes are typically found in human reproductive cells (sperm or egg)

1. A23✓
2. B46✓
3. C44✓
4. D48✓

Which pair of chromosomes determines biological sex in humans

1. AChromosome pair 1✓
2. BChromosome pair 21✓
3. CThe X and Y sex chromosomes✓
4. DChromosome pair 23 specifically referring to sex chromosomes✓

What term describes a trait that is only expressed when two copies of the responsible allele are present

1. ADominant trait✓
2. BRecessive trait✓
3. CCodominant trait✓
4. DPolygenic trait✓

What combination of sex chromosomes typically results in a biologically male individual

1. AXX✓
2. BXY✓
3. CXXY only✓
4. DYY✓

What combination of sex chromosomes typically results in a biologically female individual

1. AXX✓
2. BXY✓
3. CYY✓
4. DXO only✓

What is the process called by which a cell divides to produce two genetically identical daughter cells

1. AMitosis✓
2. BMeiosis✓
3. CFertilization✓
4. DTranscription✓

What is the process called by which reproductive cells divide to produce gametes with half the chromosome number

1. AMitosis✓
2. BMeiosis✓
3. CFertilization✓
4. DTranslation✓

What is the process by which DNA information is copied into messenger RNA

1. ATranslation✓
2. BTranscription✓
3. CReplication✓
4. DMutation✓

What is the process by which messenger RNA is used to synthesize a protein

1. ATranscription✓
2. BTranslation✓
3. CReplication✓
4. DMitosis✓

What major international scientific effort, completed in 2003, mapped the complete human genome

1. AHuman Genome Project✓
2. BCRISPR Project✓
3. CManhattan Project✓
4. DApollo Project✓

What is the term for the complete set of genetic material (DNA) present in an organism

1. AGenome✓
2. BGenotype✓
3. CPhenotype✓
4. DChromatin✓

What term describes the large-scale study of an organism's complete set of proteins

1. AGenomics✓
2. BEpigenetics✓
3. CProteomics✓
4. DMetabolomics✓

What term describes the study of how environmental factors can influence gene expression without altering the underlying DNA sequence

1. AGenomics✓
2. BEpigenetics✓
3. CProteomics✓
4. DBioinformatics✓

Who received a Nobel Prize for developing the technique to create induced pluripotent stem cells

1. AShinya Yamanaka✓
2. BJames Watson✓
3. CFrancis Crick✓
4. DRosalind Franklin✓

What term describes cells reprogrammed in the laboratory to behave like embryonic stem cells, avoiding some ethical concerns

1. AAdult stem cells✓
2. BInduced pluripotent stem cells (iPSCs)✓
3. CTotipotent cells✓
4. DGametes✓

What term describes stem cells found in specific adult tissues, generally more limited in the cell types they can become

1. AEmbryonic stem cells✓
2. BAdult (somatic) stem cells✓
3. CTotipotent cells✓
4. DZygote cells✓

Which type of stem cell has the potential to develop into virtually any type of cell in the body

1. AAdult stem cells (more limited potential)✓
2. BEmbryonic stem cells✓
3. CSkin cells (not stem cells)✓
4. DRed blood cells (not stem cells)✓

What is the term for a genetic test used to establish biological relationships, such as paternity

1. ADNA fingerprinting/profiling✓
2. BPCR alone✓
3. CGel electrophoresis alone✓
4. DKaryotyping✓

What laboratory technique separates DNA fragments based on size using an electric current through a gel medium

1. APCR✓
2. BGel electrophoresis✓
3. CCRISPR✓
4. DKaryotyping✓

What laboratory technique is commonly used to amplify small segments of DNA for analysis

1. APCR (Polymerase Chain Reaction)✓
2. BGel electrophoresis (separates, does not amplify)✓
3. CCRISPR✓
4. DSouthern blotting✓

What term describes a cross between two organisms differing in two traits, used to study inheritance patterns

1. AMonohybrid cross✓
2. BDihybrid cross✓
3. CTest cross✓
4. DBackcross✓

What term describes a cross between two organisms differing in only one trait

1. AMonohybrid cross✓
2. BDihybrid cross✓
3. CTest cross✓
4. DBackcross✓

What visual tool is commonly used in genetics to predict the probability of offspring genotypes from a cross

1. APunnett square✓
2. BPedigree chart✓
3. CKaryotype✓
4. DPhylogenetic tree✓

What term describes a chart used to trace the inheritance of a particular trait through a family across generations

1. APunnett square✓
2. BPedigree chart✓
3. CKaryotype✓
4. DGenome map✓

What term describes a visual representation showing the complete set of chromosomes in a cell, organized by size and shape

1. APunnett square✓
2. BPedigree chart✓
3. CKaryotype✓
4. DGenotype chart✓

Which genetic disorder results from an extra copy of chromosome 21, causing distinctive physical and developmental characteristics

1. ADown syndrome✓
2. BTurner syndrome✓
3. CKlinefelter syndrome✓
4. DCystic fibrosis✓

Which genetic disorder specifically affects females, resulting from a missing or partially missing X chromosome

1. ADown syndrome✓
2. BTurner syndrome✓
3. CKlinefelter syndrome✓
4. DHuntington's disease✓

Which genetic disorder specifically affects males, resulting from an extra X chromosome (XXY)

1. ADown syndrome✓
2. BTurner syndrome✓
3. CKlinefelter syndrome✓
4. DSickle cell disease✓

Which inherited disorder causes thick, sticky mucus buildup, particularly affecting the lungs and digestive system

1. ACystic fibrosis✓
2. BSickle cell disease✓
3. CHuntington's disease✓
4. DHemophilia✓

Which inherited neurological disorder causes progressive brain cell degeneration, typically appearing in mid-adulthood

1. ACystic fibrosis✓
2. BSickle cell disease✓
3. CHuntington's disease✓
4. DDown syndrome✓

What term describes traits carried on the X chromosome, often showing different inheritance patterns between males and females

1. AAutosomal traits✓
2. BSex-linked traits✓
3. CPolygenic traits✓
4. DCodominant traits✓

Colorblindness is a classic example of which type of inherited trait

1. AAutosomal dominant✓
2. BSex-linked recessive✓
3. CCodominant✓
4. DPolygenic✓

What term describes a trait controlled by multiple genes, resulting in a continuous range of phenotypes, such as human height

1. AMonogenic trait✓
2. BPolygenic trait✓
3. CSex-linked trait✓
4. DRecessive trait✓

What term describes a situation where both alleles for a trait are fully and simultaneously expressed, such as in certain blood types

1. AComplete dominance✓
2. BCodominance✓
3. CIncomplete dominance✓
4. DPolygenic inheritance✓

What term describes a situation where neither allele is completely dominant, resulting in a blended phenotype

1. AComplete dominance✓
2. BCodominance✓
3. CIncomplete dominance✓
4. DPolygenic inheritance✓

What field of biotechnology involves directly manipulating an organism's genes, such as inserting a gene from one species into another

1. AGenetic engineering✓
2. BSelective breeding✓
3. CNatural selection✓
4. DCloning (related but distinct concept)✓

What term describes the process of creating a genetically identical copy of an organism

1. AGenetic engineering✓
2. BSelective breeding✓
3. CCloning✓
4. DHybridization✓

Which famous cloned mammal, created in 1996, was the first cloned from an adult somatic cell

1. ADolly the sheep✓
2. BBessie the cow✓
3. CSnuppy the dog✓
4. DCC the cat✓

What revolutionary gene-editing technology, developed in the 2010s, allows precise modification of DNA sequences

1. ACRISPR-Cas9✓
2. BPCR (Polymerase Chain Reaction)✓
3. CGel electrophoresis✓
4. DSouthern blotting✓

What is the term for an organism that has two different alleles for a particular trait

1. AHeterozygous✓
2. BHomozygous✓
3. CHemizygous✓
4. DPolyzygous✓

What is the term for an organism that has two identical alleles for a particular trait

1. AHeterozygous✓
2. BHomozygous✓
3. CHemizygous✓
4. DPolyzygous✓

What enzyme can extend telomeres, notably active in stem cells and often reactivated abnormally in cancer cells

1. ATelomerase✓
2. BDNA polymerase (general replication enzyme)✓
3. CRNA polymerase✓
4. DHelicase✓

What is the general term for the orderly sequence of growth, DNA replication, and division that a cell undergoes

1. ACell cycle✓
2. BMetabolism✓
3. CHomeostasis✓
4. DMitosis (a phase within the broader cycle)✓

What is the term for the specific location of a gene on a chromosome

1. AGenotype✓
2. BLocus✓
3. CAllele✓
4. DPhenotype✓

What is the term for the protective cap-like structures found at the ends of chromosomes, preventing degradation

1. ACentromere✓
2. BTelomere✓
3. CNucleolus✓
4. DChromatin✓

What term describes the shortening of telomeres over successive cell divisions, associated with cellular aging

1. ATelomere elongation✓
2. BTelomere shortening (Telomere attrition)✓
3. CChromatin condensation✓
4. DCentromere duplication✓

What principle states that alleles for different traits are distributed to gametes independently of each other

1. ALaw of Segregation✓
2. BLaw of Independent Assortment✓
3. CLaw of Dominance✓
4. DLaw of Codominance✓

What is the term for the exchange of genetic material between homozygous chromosomes during meiosis, increasing genetic diversity

1. AIndependent assortment✓
2. BLinked genes✓
3. CCrossing over✓
4. DMutation✓

What principle states that allele pairs separate during gamete formation, so each gamete carries only one allele for each trait

1. ALaw of Segregation✓
2. BLaw of Independent Assortment✓
3. CLaw of Dominance✓
4. DLaw of Linkage✓

What is the term for the study of how traits are passed from parents to offspring

1. AGenetics✓
2. BEcology✓
3. CTaxonomy✓
4. DPhysiology✓

What is the term describing genes located on the same chromosome that tend to be inherited together

1. AIndependent assortment✓
2. BLinked genes✓
3. CCrossing over✓
4. DRecombination✓

What is the term for a change in the number of chromosomes in a cell, such as trisomy conditions like Down syndrome

1. APoint mutation✓
2. BChromosomal mutation (Aneuploidy)✓
3. CFrameshift mutation✓
4. DSilent mutation✓

What is the term for a mutation involving a change in a single nucleotide base in the DNA sequence

1. APoint mutation✓
2. BChromosomal mutation✓
3. CFrameshift mutation (specific type)✓
4. DDeletion mutation (general category)✓

What is the term for a mutation that inserts or deletes nucleotides, shifting the reading frame of the genetic code

1. APoint mutation✓
2. BChromosomal mutation✓
3. CFrameshift mutation✓
4. DSilent mutation✓

What is the term for a mutation that does not change the resulting amino acid due to the redundancy of the genetic code

1. APoint mutation (general)✓
2. BFrameshift mutation✓
3. CSilent mutation✓
4. DNonsense mutation✓

What is the term for a mutation that creates a premature stop codon, truncating protein production

1. APoint mutation (general)✓
2. BSilent mutation✓
3. CNonsense mutation✓
4. DMissense mutation (different effect)✓

What is the term for a mutation that changes one amino acid to a different amino acid in the resulting protein

1. ASilent mutation✓
2. BNonsense mutation✓
3. CMissense mutation✓
4. DFrameshift mutation✓

What is the term for external factors, such as radiation or certain chemicals, that can cause mutations

1. AMutagens✓
2. BCarcinogens (specifically cancer-causing subset)✓
3. CPathogens✓
4. DAllergens✓

What is the term for substances specifically known to cause cancer, often by causing mutations

1. AMutagens (broader category)✓
2. BCarcinogens✓
3. CPathogens✓
4. DTeratogens (cause birth defects specifically)✓

What is the term for a substance that can cause developmental abnormalities or birth defects in a developing embryo/fetus

1. AMutagen (general)✓
2. BCarcinogen (cancer-specific)✓
3. CPathogen✓
4. DTeratogen✓

What is the term for the complete biochemical machinery within a cell that carries out protein synthesis, involving ribosomes and RNA

1. ATranslation apparatus/machinery✓
2. BReplication fork✓
3. CNucleolus (specific structure)✓
4. DGolgi complex✓

What is the structure within the nucleus specifically responsible for producing ribosomal RNA and assembling ribosomes

1. ANucleolus✓
2. BNuclear envelope✓
3. CChromatin✓
4. DNuclear pore✓

What is the term for the loosely packed form of DNA and proteins found within the nucleus during non-dividing phases of the cell cycle

1. AChromosome (condensed form)✓
2. BChromatin✓
3. CNucleolus✓
4. DCentromere✓

What is the term for the constricted region of a chromosome where sister chromatids are joined during cell division

1. ATelomere✓
2. BCentromere✓
3. CNucleolus✓
4. DChromatin✓

What is the term for the specific sequence of three nucleotide bases in mRNA that codes for a particular amino acid

1. ACodon✓
2. BAnticodon✓
3. CGene✓
4. DAllele✓

What is the term for the complementary three-base sequence on tRNA that pairs with a codon during translation

1. ACodon✓
2. BAnticodon✓
3. CGene✓
4. DLocus✓

How many different amino acids are commonly used to build proteins in living organisms

1. A10✓
2. B15✓
3. C20✓
4. D25✓

What is the specific codon that signals the start of protein synthesis during translation

1. AAUG✓
2. BUAA✓
3. CUAG✓
4. DUGA✓

How many stop codons signal the termination of protein synthesis

1. AOne✓
2. BTwo✓
3. CThree✓
4. DFour✓

How many divisions occur during meiosis, distinguishing it from the single division of mitosis

1. AOne✓
2. BTwo✓
3. CThree✓
4. DFour✓

During which sub-phase of interphase does DNA replication specifically occur

1. AG1 phase✓
2. BS phase✓
3. CG2 phase✓
4. DM phase (mitosis itself)✓

What are the three sub-phases of interphase called

1. AG1, S, and G2 phases✓
2. BProphase, Metaphase, Anaphase✓
3. CMitosis, Meiosis, Cytokinesis✓
4. DAlpha, Beta, Gamma phases✓

What is the term for the phase of the cell cycle where the cell grows and DNA replication occurs, before mitosis begins

1. AInterphase✓
2. BMitosis✓
3. CCytokinesis✓
4. DMeiosis✓

What is the final stage following telophase, during which the cytoplasm actually divides into two separate cells

1. AInterphase✓
2. BCytokinesis✓
3. CProphase (of next cycle)✓
4. DMetaphase (of next cycle)✓

During which phase of mitosis does the nuclear membrane reform and the cell begins to divide into two

1. AProphase✓
2. BMetaphase✓
3. CAnaphase✓
4. DTelophase✓

During which phase of mitosis do sister chromatids separate and move to opposite poles of the cell

1. AProphase✓
2. BMetaphase✓
3. CAnaphase✓
4. DTelophase✓

During which phase of mitosis do chromosomes align at the cell's equatorial plate (middle)

1. AProphase✓
2. BMetaphase✓
3. CAnaphase✓
4. DTelophase✓

What is the term for the four phases of mitosis, in correct sequential order

1. AProphase, Metaphase, Anaphase, Telophase✓
2. BMetaphase, Prophase, Telophase, Anaphase✓
3. CAnaphase, Telophase, Prophase, Metaphase✓
4. DTelophase, Anaphase, Metaphase, Prophase✓

What term describes cells with only a single set of chromosomes, such as human gametes with 23 chromosomes

1. AHaploid✓
2. BDiploid✓
3. CTriploid✓
4. DPolyploid✓

What term describes cells with a full set of paired chromosomes, such as human somatic cells with 46 chromosomes

1. AHaploid✓
2. BDiploid✓
3. CTriploid✓
4. DPolyploid✓

What is the term for the cell formed immediately after fertilization, when a sperm and egg combine

1. AGamete✓
2. BZygote✓
3. CSomatic cell✓
4. DBlastocyst (a later developmental stage)✓

What is the term for the resulting cells of meiosis, specifically referring to sperm and egg cells

1. ASomatic cells✓
2. BGametes✓
3. CZygotes✓
4. DStem cells✓

What is the term for an organism's complete genetic blueprint, encoded within its DNA

1. AGenome✓
2. BProteome✓
3. CTranscriptome✓
4. DMetabolome✓

What is the term for the complete set of RNA transcripts produced by an organism's genome at a given time

1. AGenome✓
2. BProteome✓
3. CTranscriptome✓
4. DMetabolome✓

What is the general scientific field involving the collection, storage, and analysis of large-scale biological data, such as genomic sequences

1. AGenomics✓
2. BBioinformatics✓
3. CBiochemistry✓
4. DBiophysics✓

What structural protein, wrapped by DNA, helps package and organize chromatin within the nucleus

1. AHistone✓
2. BKeratin✓
3. CCollagen✓
4. DActin✓

What is the term for the process by which a cell becomes specialized to perform specific functions, such as becoming a muscle or nerve cell

1. ADifferentiation✓
2. BReplication✓
3. CMutation✓
4. DTranscription✓

What term describes a stem cell's capacity to develop into any cell type in the body, including extraembryonic tissues, characteristic of a fertilized egg

1. APluripotent✓
2. BTotipotent✓
3. CMultipotent✓
4. DUnipotent✓

What term describes a stem cell's more limited capacity to develop into a restricted range of related cell types, such as blood stem cells

1. APluripotent✓
2. BTotipotent✓
3. CMultipotent✓
4. DUnipotent✓

Which scientist is credited with the "one gene, one enzyme" hypothesis, foundational to understanding gene function

1. AGeorge Beadle and Edward Tatum✓
2. BJames Watson and Francis Crick✓
3. CGregor Mendel✓
4. DRosalind Franklin✓