(a) Meiosis and mitosis are important processes in the life cycles of organisms. Fig. 3.1 shows the life cycles of two different organisms. Organism 1 has a simple life cycle. Organism 2 has a complex life cycle. It has a stage A that produces spores and a stage B that produces gametes. In the diagrams, the haploid number of chromosomes is represented by n. The diploid number of chromosomes is represented by 2n.
(i) Table 3.1 shows the letters P to T in Fig. 3.1 and the type of nuclear division.
Place a tick (✓) in each row to indicate the type of nuclear division that occurs at each of the letters, P to T.
(ii) State the name of process W shown in Fig. 3.1.
(iii) An embryo contains stem cells.
Complete the sentences about stem cells and body cells. Stem cells are ………. cells that divide by ……….. to produce daughter cells that can become …………. for a specific function. Most body cells in an organism contain the same genes, but many genes in a particular cell are not ……… because the cell only makes the specific ………. it needs.
(b) State the events in the life cycle diagram for organism 1 in Fig. 3.1 that would not be present in a life cycle diagram for asexual reproduction.
