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7.1 Cytoplasmic Inheritance & Organelle Genomes — Test 1
Q1. Maternal (cytoplasmic) characteristics are inherited mainly through which organelle?✓ Mitochondria
Q2. Which structure carries extranuclear genetic material?✓ Mitochondria
Q3. Extrachromosomal circular DNA is found in:✓ Prokaryotes, eukaryotic mitochondria and plastids
Q4. The first experimental evidence for maternal inheritance of cytoplasmic genes came from the work of:✓ Carl Correns
Q5. Cytoplasmic inheritance through kappa particles is observed in:✓ Paramecium
Q6. Inheritance of the 'Poky' phenotype in Neurospora crassa is an example of:✓ Mitochondrial inheritance
Q7. The respiratory-deficient mutants 'Poky' (Neurospora) and 'Petite' (yeast) typically have defective:✓ Cytochrome (oxidase) components of the respiratory chain
Q8. Which of the following is NOT a feature/type of extranuclear inheritance?✓ Strict Mendelian (sexual) segregation
Q9. Which statement about cytoplasmic inheritance is CORRECT?✓ It is usually maternally inherited
Q10. Which statement about cytoplasmic inheritance is INCORRECT?✓ Organelle genes can be mapped onto the nuclear linkage groups
Q11. Mitochondrial DNA in humans is inherited from:✓ The mother only
Q12. Which statement about the human mitochondrial genome is CORRECT?✓ It has essentially no introns and is very compact
Q13. The number of protein-coding genes in the human mitochondrial genome is:✓ 13
Q14. The human mitochondrial genome encodes how many rRNA genes?✓ 2
Q15. Which set of statements about the human mitochondrial genome is correct?✓ Replication of H and L strands begins at distinct origins; the D-loop is a triple-stranded region; transcription proceeds from promoters on both strands
Q16. Mitochondrial DNA is especially useful for evolutionary/phylogenetic studies because:✓ It is maternally inherited (no recombination), giving clear lineages
Q17. DNA barcoding for animal molecular taxonomy commonly uses:✓ Mitochondrial cytochrome c oxidase I (COI) gene sequences
Q18. Cytoplasmic male sterility (CMS) arises from an interaction between the:✓ Nucleus and mitochondria
Q19. Cytoplasmic male sterility (CMS) results from which change in the mitochondrial genome?✓ A mutation (often a novel chimeric ORF)
Q20. Match each example with its inheritance mechanism and select the correct option.✓ A-ii, B-i, C-iv, D-iii