3.6 Linkage, Recombination & Molecular Markers — Test 2

Start Here Introduction ▾

Welcome! 3.6 Linkage, Recombination & Molecular Markers — Test 2 — 20 questions, CSIR-NET style.

What this test covers

Crossover frequency, map distance & linkage groups
Recombination frequency calculations & the 50% limit
LOD scores, molecular markers (RFLP, SSR)
Somatic-cell hybrids & Neurospora centromere mapping

How to use

Tap the test below — it opens on its own full screen. Use ← All tests at the top to come back.
Each question has a 40-second timer. Answer, then Submit to see your score.
Tap 📋 View Solution under any question for a full explanation.

Open Review at the bottom for a quick revision list of every question with its correct answer.

All 20 Questions Review ▾

Quick revision: every question with its correct answer. For the full explanation, open the test and tap View Solution.

3.6 Linkage, Recombination & Molecular Markers — Test 2

Q1. The frequency of crossing over between two genes is directly proportional to the:✓ Distance between the genes

Q2. In a genetic map, the distance between two genes is measured in:✓ Centimorgans (map units)

Q3. The maximum recombination frequency that can be observed between two loci is:✓ 50%

Q4. A genetic map built from recombination-frequency data is called a:✓ Linkage map

Q5. The number of linkage groups in a human male is:✓ 24

Q6. If an organism has 12 linkage groups, its haploid chromosome number is:✓ 12

Q7. After meiosis, 20% of the gametes are recombinant for two genes. The map distance between them is:✓ 20 cM

Q8. Genes A and B are 10 cM apart. In a test cross of AB/ab (cis), the proportion of AB/ab (parental) offspring of that type is about:✓ 45%

Q9. A two-point test cross of two UNLINKED genes gives a phenotypic ratio of:✓ 1:1:1:1

Q10. The ratio of the observed number of double crossovers to the expected number is the:✓ Coefficient of coincidence

Q11. Recombination does NOT occur during meiosis in:✓ Drosophila males

Q12. Which molecular marker is NON-PCR-based?✓ RFLP

Q13. A LOD score of 3 corresponds to odds in favour of linkage of:✓ 1000 to 1

Q14. The most suitable marker class for marker-assisted selection of agronomic traits is generally:✓ EST-SSR (expressed-sequence microsatellites)

Q15. Interspecific somatic-cell hybrids (e.g. human-mouse) have been especially useful for:✓ Physical gene mapping (assigning genes to chromosomes)

Q16. The fusion of human and mouse cells to make somatic-cell hybrids is commonly mediated by:✓ Inactivated Sendai virus (or PEG)

Q17. A molecular marker generally CANNOT be used directly for:✓ Identifying the expressed protein product

Q18. Neurospora is an ideal organism for determining whether allele segregation occurred at the first or second meiotic division because it:✓ Retains the ordered products of meiosis in an ascus

Q19. In Neurospora, second-division segregation patterns in the ascus are used to measure the distance between a gene and its:✓ Centromere

Q20. Match each term with its description and select the correct option.✓ A-ii, B-iv, C-i, D-iii