A nursery keeps a group of spider plants in a greenhouse where the light, water and mineral ion availability remain constant. Spider plants can produce plantlets asexually on long stems.
Staff recorded the number of plantlets that had rooted.
| Time in weeks | Number of rooted plantlets |
|---|---|
| 0 | 12 |
| 4 | 24 |
| 8 | 42 |
| 12 | 72 |
The nursery compares the count at week 12 with the count at week 4. Calculate the percentage increase over this interval.
Explain one advantage of the plantlets having the same genes as the parent plants while the greenhouse conditions remain constant.
The nursery also produces a group of offspring by sexual reproduction. Suggest why the parent plants may show less growth while producing these offspring.
92 exam-style questions on Edexcel GCSE Biology 3.1 Reproduction and meiosis, covering 3.1.1 Advantages and disadvantages of reproduction and 3.1.2 Role of meiotic cell division. Each one has a worked solution and a mark scheme showing where the marks go.