Question

A Planaria worm is cut horizontally in the middle into two halves P and Q such that the part P contains the whole head of the worm. Another Planaria worm is cut vertically into two halves R and S in such a way that both the cut pieces R and S contain half head each. Which of the cut pieces of the two Planaria worms could regenerate to form the complete respective worms?

Options

• only P

• only R and S

• P, R and S

• P, Q, R and S

Answer 1

P, Q, R and S

Explanation:

Planaria has a high power of regeneration. Any body fragment containing living cells can regenerate into a complete worm. Therefore, all four pieces (P, Q, R and S) can regenerate into complete Planaria worms.