Multiple choice

Which among the following statements regarding the cytokinesis in animal cells is false?

  1. It begins shortly after the onset of sister chromatid separation.

  2. A contractile ring, made of muscle myosin II and actin filaments, assembles parallelly at the cell cortex.

  3. The process of abscission physically cleaves this midbody into two.

  4. Abscission depends on septin filaments.

  5. The position at which the contractile ring assembles is dictated by the mitotic spindle.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A contractile ring, made of non-muscle myosin II and actin filaments, assembles equatorially (in the middle of the cell) at the cell cortex (adjacent to the cell membrane). Myosin II uses the free energy released when ATP is hydrolysed to move along these actin filaments, constricting the cell membrane to form a cleavage furrow.

Keep practicing — related questions