This chapter explains how new individuals form and how they grow. The four lessons go from making gametes, to fertilisation, to reading graphs about cycles and growth.
It is part of SPM Biology, and it relies on the cell division chapter for mitosis and meiosis.
How do the four lessons connect?
Each lesson follows the life story of a new individual.
- Comparing gametogenesis within syllabus scope shows how sperm and ova are made.
- Explaining fertilisation and early development follows the zygote to implantation.
- Interpreting hormonal-cycle graphs educationally teaches you to read the hormone graphs of the menstrual cycle.
- Reading growth curves and identifying phases shows how to describe growth over time.
What does one timeline show?
Start with meiosis in the testis and ovary, which forms haploid gametes. A sperm reaches an ovum in the oviduct, and fertilisation forms a diploid zygote. The zygote divides by mitosis into a ball of cells that travels to the uterus and implants in its lining.
The lining has been built by hormones in the cycle, and once the embryo develops, the new individual grows by mitosis and cell enlargement. You can chart that growth as a curve with phases. One timeline uses meiosis, mitosis, hormones and a graph.
Who should start where?
If sperm and ovum formation blur together, begin with lesson one. If you can describe gametes but the events after fertilisation are muddled, start at lesson two. If graphs are your weak point, go straight to lesson three or four.
Test yourself with the reproduction, development and growth practice set.
When does extra help make sense?
Questions in this chapter can combine a description with a graph, so marks depend on careful reading. A teacher who works through your answers can show where you described the wrong part of the graph or swapped the hormone.
If that sounds useful, see online one-to-one Biology tuition and mention reproduction, development and growth when you enquire.