Question 45 of 68
Q.During Karyotyping technique, substance that stops mitosis at metaphase in foetal cells is
(a) interferon
(b) colchicine
(c) endonuclease
(d) transcriptase
Puducherry TnboardTamil Nadu HSC (DGE) Board 2016MCQ· 1mImportance★★★★★
66% · 45/68 Questions
You're viewing a preview — the full solution, concept, methods & PYQ mapping are locked.
Start your 14-day free trial to unlock the full solution →Colchicine blocks mitotic spindle formation, arresting dividing cells at metaphase so their chromosomes can be studied in karyotyping.
Colchicine binds to tubulin and prevents microtubule (spindle-fibre) polymerisation, so cells cannot proceed past metaphase — the stage where chromosomes are maximally condensed and easiest to visualise and count, which is exactly what karyotyping (used to detect chromosomal disorders such as Down or Klinefelter syndrome) needs. Interferon is an antiviral signalling protein, endonucleases cut DN …
Unlock everything free for 14 days
- Full step-by-step solutions
- Concept-first explanations
- Methods, shortcuts & mistakes
- PYQ mapping + timed mock tests
Full access for 14 days. No credit card required.