Cell division: mitosis and the cell cycleIB MYP Biology: Flashcards

Exam questions on Cell division: mitosis and the cell cycle

1. A child falls over and cuts her knee. Over the next week the cut heals, because the skin cells next to the wound divide to replace the cells that were damaged.
   Explain why mitosis is needed for the cut to heal.2 marks
2. A spider plant grows small plantlets on long stems. When these are planted in soil, each plantlet grows into a new plant that looks identical to the parent plant.
   State two other uses of mitosis in a living organism, apart from asexual reproduction.2 marks
3. A student wants to find out whether cells at the tip of an onion root divide more often than cells further up the root. She cuts a thin slice from the tip of the root and another slice from 2 cm higher up. She stains each slice to show the nuclei and views it under a light microscope, counting how many cells are dividing.
   State a testable hypothesis for the investigation, with a scientific reason, and identify the independent variable.3 marks