Which structure helps distribute chromosomes to new cells during cell division?

• A. Tight junction protein complexes
• B. Intermediate filaments (e.g., keratin)
• C. Mitotic spindle (spindle microtubules)
• D. Actin microfilaments of the cell cortex

Answer: (C)

Verified step by step guidance

1. Understand the role of each cellular structure listed in the problem: Tight junction protein complexes, Intermediate filaments, Mitotic spindle (spindle microtubules), and Actin microfilaments.
2. Recall that tight junction protein complexes are involved in creating barriers between cells to prevent leakage of molecules, not in chromosome distribution.
3. Recognize that intermediate filaments, such as keratin, provide mechanical support and structural integrity to cells but do not participate in chromosome movement during cell division.
4. Identify that the mitotic spindle, composed of spindle microtubules, is responsible for attaching to chromosomes and pulling them apart to opposite poles of the cell during mitosis, ensuring proper chromosome distribution.
5. Note that actin microfilaments mainly contribute to cell shape and movement, especially in the cell cortex, but are not directly involved in chromosome segregation during cell division.