Spindle Fibres

Spindle fibres constitute mitotic and meiotic spindle during cell division. They are formed by microtubules and play an important role during nuclear division. They are responsible for the segregation of sister chromatids and movement of chromosomes during mitotic and meiotic division.

What is Spindle Fibres?


A network of filament that forms mitotic and meiotic spindle during cell division is termed as spindle fibre. Movement of chromosomes during mitosis and meiosis cell division is due to spindle fibres.

What are Spindle Fibres made of?

Structure, Formation and Location

  • Spindle fibres are made up of tubulin proteins and RNA. It is composed of microtubules, which is a polymer of 𝜶 and 𝞫-tubulin dimer
  • They are formed from the centrosome, they are formed at the opposite poles during cell division and attach to chromosomes at the equatorial plate
  • Centrosomes always have assembled microtubules. Spindle fibres start increasing in length on getting signal for cell division
  • During metaphase, they radiate from centrioles and get attached to arms or kinetochore of chromosomes
  • At anaphase stage of cell division, spindle fibres pull sister chromatids towards opposite poles
  • Spindle fibres, along with associated proteins, condensed chromosomes and centrosomes or asters form the spindle apparatus

Spindle Fibers Function

  • Spindle fibres help in the division of genetic component of the cell during division
  • Spindle fibres are formed during both mitosis and meiosis cell division
  • Spindle fibres get attached to kinetochores and arms of chromosomes and help in segregation and movement of chromatids
  • During metaphase, chromosomes get aligned in the middle with the help of spindle and then move to the opposite poles during anaphase stage

Explore all the important topics aligned with updated NEET syllabus, only at BYJU’S. Check NEET – Important topics and Preparation Tips for all the important concepts and related topics.

Test your Knowledge on Spindle Fibres

Leave a Comment

Your Mobile number and Email id will not be published. Required fields are marked *